Manual Previous Revision

3714 Kinnear Place
Saskatoon, SK
Canada
S7P 0A6
Ph: (306) 373-5505
Fx: (306) 374-2245 www.littelfuse.com/relayscontrols
SE-330HV MANUAL
NEUTRAL-GROUNDING-RESISTOR MONITOR
REVISION 4-A-112913
LITTELFUSE STARTCO
NEUTRAL-GROUNDING-RESISTOR SE-330HV
MONITOR
GROUND
FAULT
RESISTOR
FAULT
DIAGNOSTIC
TRIP
TRIP
CALIBRATED
RELAY K1
8
6
10
15
20
40
60
POWER
4
80
2
100
GF TRIP LEVEL
(% CT RATING)
0.5 0.7 1.0
0.4
0.3
0.2
0.1
2.0
3.0
5.0
10.0
850
650
500
1000
1700
4000
6000
300
8500
100
10000
VN TRIP LEVEL
(S5
(S5
200 K Ω VN x 2)
100 K Ω VN x 1)
CAL
GF TRIP TIME (s)
RESET
Copyright  2012 Littelfuse Startco.
All rights reserved.
Publication: SE-330HV-M
Document: S95-C330-0H000
Printed in Canada.
Page i
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
PAGE
TABLE OF CONTENTS
PAGE
1. General ................................................................... 1
1.1 Modern Resistance-Grounded Systems ................... 1
1.2 SE-330HV NGR Monitoring ................................... 1
2. Operation ................................................................ 2
2.1 Settings .................................................................... 2
2.1.1 GF Trip Time ................................................ 2
2.1.2 GF Trip Level ............................................... 2
2.1.3 VN Trip Level ............................................... 2
2.1.4 Configuration Settings .................................. 3
2.1.4.1 Spare (S1) ........................................ 3
2.1.4.2 Trip-Relay Mode (S2) ...................... 3
2.1.4.3 Ground-Fault-Trip Latch (S3).......... 3
2.1.4.4 Resistor-Fault-Trip Latch (S4)......... 3
2.1.4.5 Sensing-Resistor Selection (S5)....... 3
2.1.4.6 Frequency (S6)................................. 3
2.1.4.7 Spare (S7) ........................................ 3
2.1.4.8 Upgrade Enable (S8)........................ 3
2.2 Calibration ............................................................... 3
2.3 Trip Indication and Reset......................................... 4
2.4 Remote Operation .................................................... 4
2.5 Relay K1 LED ......................................................... 4
2.6 Unit Healthy Output ................................................ 4
2.7 Diagnostic LED ....................................................... 4
2.8 Analog Output ......................................................... 5
3.
3.1
3.2
3.3
3.4
Installation .............................................................. 5
SE-330HV ............................................................... 5
Sensing Resistor....................................................... 5
Ground-Fault CT ................................................... 17
Isolated Ground Connection .................................. 21
4. Communications .................................................. 22
4.1 Local Communication Port .................................... 22
4.1.1 Local Data Acquisition ............................... 22
4.1.2 Local Communications Commands ............ 22
4.1.3 Firmware Upgrade ...................................... 22
4.2 Network Communications ..................................... 22
5.
Troubleshooting ................................................... 23
6.
6.1
6.2
6.3
Technical Specifications ...................................... 24
SE-330HV ............................................................. 24
Sensing Resistors ................................................... 25
Current Sensors ...................................................... 26
7.
Ordering Information ......................................... 26
8.
Warranty .............................................................. 27
9. Test Procedures ....................................................28
9.1 Resistor-Fault Tests ................................................28
9.1.1 Calibration and Open Test ..........................28
9.1.2 Voltage Test ...............................................28
9.2 Sensing-Resistor Test .............................................28
9.3 Analog-Output Test ................................................28
9.4 Ground-Fault Performance Test .............................28
LIST OF FIGURES
FIGURE
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
PAGE
Configuration Switches ............................................3
Analog-Output Connections .....................................5
SE-330HV Connection Diagram ..............................6
SE-330HV Outline and Panel-Mounting Details......7
SE-330HV Outline and Surface-Mounting Details ..8
SE-IP65CVR-G Weatherproof Cover Outline .........9
SE-IP65CVR-G Weatherproof Cover
Installation ..............................................................10
ER-15KV Sensing Resistor ....................................11
ER-25KV Sensing Resistor ....................................12
ER-35KV Sensing Resistor ....................................13
ER-72KV Sensing Resistor Outline .......................14
ER-72KV Sensing Resistor Mounting Details .......15
ER-1000HV Sensing Resistor ................................16
ER-1000HV Simplified Connection Diagram ........17
EFCT-1 Ground-Fault Current Sensor ...................18
SE-CS30-70 Ground-Fault Current Sensor ............19
EFCT-26 and SE-CS30-26 GroundFault Current Sensors .............................................20
RK-332 Remote Indication and Reset ....................21
Simplified Isolated-Ground Connection .................21
Ground-Fault-Test Circuit ......................................29
LIST OF TABLES
TABLE
1
2
3
4
PAGE
Typical Values for Tripping Systems .......................2
Ground-Fault Trip Levels for Selected CT’s ............2
RS-232 DB-9 Terminals .........................................22
Ground-Fault-Test Record......................................29
DISCLAIMER
Specifications are subject to change without notice.
Littelfuse Startco is not liable for contingent or
consequential damages, or for expenses sustained as a result
of incorrect application, incorrect adjustment, or a
malfunction.
SE-330HV Neutral-Grounding-Resistor Monitor
1. GENERAL
1.1 MODERN RESISTANCE-GROUNDED SYSTEMS
A high-resistance-grounded system uses a neutralgrounding resistor (NGR) with a low let-through current
to limit ground-fault current. This is an improvement
over low-resistance or solidly-grounded systems because,
in those systems, a ground-fault flash hazard exists and a
ground fault can result in substantial point-of-fault
damage. High-resistance grounding eliminates these
problems and modern ground-fault protection operates
reliably at low current levels.
Furthermore, the
probability of an arc-flash incident is significantly
reduced in a high-resistance-grounded system.
NGR selection depends on system charging current and
whether the system is an alarm-only or a tripping system.
Alarm-only systems are usually restricted to system
voltages up to 5 kV with NGR let-through currents of 5 A
or less. Occasionally, alarm-only systems up to 15 kV
and up to 10 A are used; however, they are not common
because a ground fault on such a system tends to escalate
to a phase-to-phase fault before the ground fault can be
located and cleared.
System charging current is the capacitive current that
flows to ground when a bolted ground fault occurs. This
current can be calculated or measured. For small systems,
the magnitude of charging current can be conservatively
estimated as ½ A per 1,000 kVA on low-voltage systems
and 1 A per 1,000 kVA on medium-voltage systems.
In an alarm-only system or in a tripping system without
selective coordination, choose an NGR with a let-through
current larger than the system charging current and set
the pick-up current of ground-fault devices at or below
50% of the NGR let-through current.
In a tripping system with selective coordination, use
ground-fault devices with a definite-time characteristic to
achieve time coordination. Use the same pick-up current
for all ground-fault devices—this value must be larger
than the charging current of the largest feeder. Select an
NGR with a let-through current between five and ten
times the pick-up current of the ground-fault devices.
Do not use a grounding transformer with a low-voltage
resistor:
 The combined cost of a transformer and a lowvoltage resistor is more than the cost of a resistor
rated for line-to-neutral voltage.
 A transformer saturated by a ground fault through a
rectifier can make ground-fault protection
inoperative.
 Transformer inrush current up to twelve times rated
current can cause a ground-fault voltage larger than
expected.
 A parallel transformer winding makes it difficult to
monitor NGR continuity.
 A transformer can provide the inductance necessary
to cause ferroresonance if the NGR opens.
Page 1
Rev. 4-A-112913
Following these guidelines will reduce the flash hazard,
reduce point-of-fault damage, achieve reliable groundfault protection, and ensure a stable system not subject to
ferroresonance.
1.2 SE-330HV NGR MONITORING
The SE-330HV is a microprocessor-based neutralgrounding-resistor monitor that detects NGR failures and
ground faults in resistance-grounded systems.
The
SE-330HV measures NGR resistance, NGR current, and
transformer or generator neutral-to-ground voltage. The
components required to monitor an NGR are an
SE-330HV, a 100- or 200-k ER-series sensing resistor,
and a current transformer (CT).
Power-circuit elements, other than neutral-connected
NGR’s, that purposefully connect the power system to
ground are often not compatible with SE-330HV NGR
monitoring.
These elements include single-phase
grounding transformers, grounded-wye-primary PT’s, and
grounded-wye-primary power transformers.
The SE-330HV continuously measures NGR resistance
in an unfaulted system, and it will trip on resistor fault if
NGR resistance varies from its calibrated value. When a
ground fault occurs, voltage is present on the neutral and
NGR current will flow if the NGR is healthy. The
SE-330HV will trip on ground fault if fault current
exceeds the GF TRIP LEVEL setting for an interval equal
to the GF TRIP TIME setting. However, if the NGR fails
open during a ground fault, it is possible for fault
resistance to satisfy the NGR resistance measurement. To
detect this double-fault condition, the SE-330HV
measures neutral voltage. If neutral voltage exceeds the
VN TRIP LEVEL setting, and if NGR current is less than
5% of the CT rating, the SE-330HV will trip on resistor
fault. If the resistor-fault circuit is tripped and the neutral
voltage exceeds the VN TRIP LEVEL setting for an
interval greater than the GF TRIP TIME setting, the
ground-fault circuit will also trip.
Ground-fault current is sensed by a CT with a 1- or 5-A
secondary, or by a CT (EFCT-x or SE-CS30-x) with a
50-mA secondary. The trip level of the ground-fault
circuit is adjustable from 2 to 100% of the CT rating and
trip time is adjustable from 0.1 to 10.0 seconds.
The SE-330HV has four output relays. Relay K1 is the
trip relay. Relays K2 and K3 provide ground-fault and
resistor-fault indication. K4 is a solid-state relay that
provides UNIT HEALTHY indication. Relay K1 will
operate on either a resistor fault or a ground fault, and it
can be set to operate in the fail-safe or non-fail-safe mode
for undervoltage or shunt-trip applications.
Additional features include LED trip indication, trip
memory, front-panel and remote reset, 4–20-mA analog
output, RS-232 local communications, data logging, and
optional network communications.
Page 2
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
2.1.3 VN TRIP LEVEL
The SE-330HV uses a DFT algorithm to measure the
fundamental component of neutral voltage.
Calculate the voltage across the NGR when NGR
current is equal to the pick-up current of the ground-fault
circuit. Set the VN TRIP LEVEL at the next largest
value. The VN TRIP LEVEL range is 100 to 10,000 V
with switch S5 in the 100-k (Vx1) position, and the
range is 200 to 20,000 V with switch S5 in the 200-k
(Vx2) position. See Fig. 1 and Section 2.1.4.5.
If neutral voltage is greater than the VN TRIP LEVEL
setting for 12 seconds and ground-fault current is less
than 5% of the CT rating, the SE-330HV will trip on
resistor fault. If the resistor-fault circuit is tripped and
the neutral voltage exceeds the VN TRIP LEVEL setting
for an interval greater than the GF TRIP TIME setting,
the ground-fault circuit will also trip.
Typical values for 15-, 25- and 100-A tripping systems
are shown in Table 1. Refer to the NGR Monitor SetPoint Assistant at www.littelfuse.com/protectionrelays
for other systems.
2. OPERATION
2.1 SETTINGS
2.1.1 GF TRIP TIME
GF TRIP TIME (definite time) is adjustable from 0.1 to
10.0 seconds. Time-coordinated ground-fault protection
requires this setting to be longer than the trip times of
downstream ground-fault devices.
A trip-time accumulator provides a ground-fault memory
function for detection of intermittent faults. The accumulated
time increases when a ground fault is detected and decreases
when a ground fault is not detected. A trip will eventually
occur when the time for fault current above the trip level is
greater than the time for fault current below the trip level.
2.1.2 GF TRIP LEVEL
The SE-330HV uses a Discrete-Fourier Transform
(DFT) algorithm to measure the fundamental component
of NGR current.
Choose an NGR let-through current and a ground-fault
trip level according to the guidelines in Section 1.1.
Set the ground-fault trip level as a percentage (2, 4, 6, 8,
10, 15, 20, 40, 60, 80, or 100) of the CT-primary rating.
Inputs are provided for 5-, 1-, and 0.05-A-secondary
CT’s. Typical values for 15-, 25-, and 100-A tripping
systems are shown in Table 1. Ground-fault trip levels
for selected CT’s are shown in Table 2. Refer to
the
NGR
Monitor
Set-Point
Assistant
at
www.littelfuse.com/protectionrelays for other systems.
NOTE: A resistor-fault trip is held off if the groundfault current is above 5% of the CT rating.
TABLE 1. TYPICAL VALUES FOR TRIPPING SYSTEMS
System
Voltage
(Volts)
7,200
14,400
7,200
14,400
25,000
35,000
72,000
Neutral-Grounding
Resistor
Current
Resistance
(Amperes)
(Ohms)
15
277
15
554
25
166
25
332
25
577
25
808
100
420
Model
ER-15KV
ER-15KV
ER-15KV
ER-15KV
ER-25KV
ER-35KV
ER-72KV
Sensing
Resistor
Resistance
(Switch S5 Setting)
100 k
100 k
100 k
100 k
100 k
100 k
200 k
Ground-Fault
Trip Level
VN Trip
Level
(Amperes)
3.0
3.0
5.0
5.0
5.0
5.0
20.0
(Volts)
850
1,700
850
1,700
4,000
6,000
6,000 x 2 = 12,000
TABLE 2. GROUND-FAULT TRIP LEVELS FOR SELECTED CT’S
GF TRIP
LEVEL
(%)
2
4
6
8
10
15
20
40
60
80
100
EFCT-x
5:0.05
(Amperes)
0.10
0.20
0.30
0.40
0.50
0.75
1.00
2.00
3.00
4.00
5.00
* Setting not recommended.
SE-CS30-x
30:0.05
(Amperes)
0.60
1.20
1.80
2.40
3.00
4.50
6.00
12.0
18.0
24.0
30.0
50:1
50:5
(Amperes)
*
*
*
*
5
7.5
10
20
30
40
50
100:1
100:5
(Amperes)
*
*
*
8
10
15
20
40
60
80
100
200:1
200:5
(Amperes)
*
*
12
16
20
30
40
80
120
160
200
400:1
400:5
(Amperes)
*
16
24
36
40
60
80
160
240
320
400
SE-330HV Neutral-Grounding-Resistor Monitor
2.1.4 CONFIGURATION SETTINGS
Eight configuration switches (S1 to S8) and a
calibration push button are located behind the access
cover on the front panel. See Fig. 1.
Page 3
Rev. 4-A-112913
2.1.4.6 FREQUENCY (S6)
Set switch S6 to 50 or 60 Hz to tune the digital filter to
the line frequency of the monitored system.
2.1.4.7 SPARE (S7)
CALIBRATION PUSH BUTTON
CAL
SPARE
FAIL-SAFE
S1
S2 NON-FAIL-SAFE
LATCHING GF TRIP
S3 NON-LATCHING GF TRIP
LATCHING RF TRIP
S4 NON-LATCHING RF TRIP
200 kΩ
50 Hz
SPARE
RUN
S5 100 kΩ
2.1.4.8 UPGRADE ENABLE (S8)
Set switch S8 to RUN for normal operation or to
UPGRADE to enable firmware upgrades. Changes in
switch S8 settings are recognized only when supply
voltage is cycled. Protection is disabled after supply
voltage is cycled with S8 in the UPGRADE position.
See Section 4.1.3.
S6 60 Hz
S7
S8 UPGRADE
NOTE: DEFAULT SETTINGS SHOWN.
FIGURE 1. Configuration Switches.
2.1.4.1 SPARE (S1)
2.1.4.2 TRIP-RELAY MODE AND TRIP MEMORY (S2)
Set switch S2 to select the operating mode of trip relay
K1. In the non-fail-safe mode, relay K1 energizes and its
contact closes when a trip occurs. The non-fail-safe mode
can be used to trip shunt-trip circuit breakers. In the nonfail-safe mode, SE-330HV trips are reset when supply
voltage is cycled.
In the fail-safe mode, relay K1 energizes and its contact
closes if there are no trips. Contacts open if there is a trip, a
loss of supply voltage, or a processor failure. In the fail-safe
mode, SE-330HV trips are not reset when supply voltage is
cycled.
NOTE: Switch S2 does not affect the operating modes of
relays K2, K3, and K4.
2.1.4.3 GROUND-FAULT-TRIP LATCH (S3)
Set switch S3 to select latching or non-latching groundfault-circuit operation. See Section 2.3.
2.1.4.4 RESISTOR-FAULT-TRIP LATCH (S4)
Set switch S4 to select latching or non-latching resistorfault-circuit operation. See Section 2.3
2.1.4.5 SENSING-RESISTOR SELECTION (S5)
Set switch S5 to the resistance of the sensing resistor. For
the ER-15KV, ER-25KV, and ER-35KV, select 100 k.
For the ER-72KV select 200 k. Switch S5 sets the
resistor-fault trip value and the VN TRIP LEVEL range. See
Section 2.1.3.
2.2 CALIBRATION
The SE-330HV measures the resistance change of the
NGR relative to the NGR-resistance value determined at
the time of calibration. Calibrate the SE-330HV on new
installations, if the NGR is changed, or if the sensing
resistor is changed.
NOTE: If the SE-330HV is not calibrated and is supplied
from the load side of the breaker (non-fail-safe mode),
calibrate within 12 seconds of power-up or it may trip and
interrupt its supply.
The CALIBRATION push button is located behind the
access cover on the front panel, and it is recessed to
prevent inadvertent activation.
NOTE:
Calibration must be performed with the
SE-330HV connected to the sensing resistor and NGR of
the installed system.
To calibrate, press and hold the CALIBRATION push
button until the green CALIBRATED LED turns off and
returns to on (if the LED is already off, press and hold
until the LED turns on). Calibration takes approximately
two seconds. If calibration is not successful, a resistorfault trip occurs, the RESISTOR FAULT TRIP LED will
be on, the CALIBRATED LED will be off, and the
DIAGNOSTIC LED will flash the calibration-error code.
See Section 2.7.
If latching resistor fault (switch S4) is selected, the
calibration-error code flashes until RESET is pressed
even if the CALIBRATED LED is on.
The calibration value is stored in non-volatile memory.
SE-330HV Neutral-Grounding-Resistor Monitor
Page 4
Rev. 4-A-112913
2.3 TRIP INDICATION AND RESET
Red LED's and indication relays indicate ground-fault
and resistor-fault trips—indication relays K2 and K3 are
energized on trip. When a trip occurs with latching
operation selected, the SE-330HV remains tripped until
reset. See Sections 2.1.4.3 and 2.1.4.4. Terminals 15 and
16 are provided for remote reset as shown in Fig. 3. The
reset circuit responds only to a momentary closure so that a
jammed or shorted switch does not prevent a trip. The
front-panel RESET switch is inoperative when terminal 15
is connected to terminal 16. If non-latching operation is
selected, trips and corresponding indication automatically
reset when the fault clears and power-up trip memory is
defeated even when configuration switch S2 is set to
fail-safe. Automatic reset time is 2.8 s maximum.
The red DIAGNOSTIC LED annunciates latched
calibration-error and remote trips. See Section 2.7.
When supply voltage is applied with switch S2 set to
FAIL-SAFE, the SE-330HV returns to its state prior to
loss of supply voltage. When supply voltage is applied
with switch S2 set to NON-FAIL-SAFE, SE-330HV trips
are reset. When a local, remote, or network reset is issued,
both trip LED's will flash if they are off.
Resistor-fault-trip reset can take up to one second.
Resistor-fault trip-memory can take up to 3 s after
SE-330HV power up.
2.7 DIAGNOSTIC LED
The DIAGNOSTIC LED is used to annunciate trips
without individual LED indication. The number of short
LED pulses between pauses indicates the cause of the trip.
2.4 REMOTE OPERATION
Relays K2 and K3 can be used for remote indication,
and terminals 15 and 16 are provided for remote reset.
RK-332 Remote Indication and Reset components are
shown in Fig. 18. Connect them as shown in Fig. 3.
RK-332 components are not polarity sensitive.
Network-enabled SE-330HV’s can be remotely tripped
and reset by the network master. The red DIAGNOSTIC
LED indicates a network-initiated trip. See Section 2.7.
Refer to the appropriate SE-330 communications manual.
Clock-Failure Trip (8 short):
CPU reset was caused by an internal clock failure.
2.5 RELAY K1 LED
The yellow RELAY K1 LED follows the state of relay
K1 and is on when K1 is energized (contact closed).
2.6 UNIT HEALTHY OUTPUT
UNIT HEALTHY relay K4 is energized when the
processor is operating. It can be ordered with N.O. or
N.C. contacts. See Section 7.
NOTE: The output changes state momentarily during a
processor reset.
NOTE: K4-contact rating is 100 mA maximum.
Calibration-Error Trip (1 short):
The calibration resistance of the NGR is outside the
calibration range. See Section 6.1.
Remote Trip (2 short):
The SE-330HV has been tripped by a remote-trip
command from the communications interface.
EEPROM-Error Trip (3 short):
An EEPROM error has been detected.
A/D-Converter-Error Trip (4 short):
An A/D-converter error has occurred.
Software-Interrupt Trip (5 short):
CPU reset was caused by a software interrupt.
Illegal-Opcode Trip (6 short):
CPU reset was caused by an illegal Opcode.
Watchdog Trip (7 short):
CPU reset was caused by the watchdog.
CPU Trip (9 short):
This code is displayed if the supply is cycled after one
of the previous four errors occurred.
Resistor-fault trips occur with all of the above trips.
Ground-fault trips occur with all of the above trips except
the calibration-error trip and the A/D-converter-error trip.
See Troubleshooting Section 5.
SE-330HV Neutral-Grounding-Resistor Monitor
2.8 ANALOG OUTPUT
An isolated 4–20-mA output indicates NGR current
with full-scale output corresponding to the CT rating. An
internal 24-Vdc supply allows the analog output to be
connected as a self-powered output. Power from an
external supply is required for loop-powered operation.
See Fig. 2.
+24V 18
+
19
-
20
0V
21
SELF-POWERED
+24V 18
+
19
-
20
0V
21
+
LOOP
SUPPLY
LOOP POWERED
FIGURE 2. Analog-Output Connections.
3. INSTALLATION
3.1 SE-330HV
Outline and panel-cutout dimensions for the SE-330HV
are shown in Fig. 4. To panel mount the SE-330HV,
insert it through the panel cutout and secure it with four
8-32 locknuts and flat washers (included).
If an optional SE-IP65CVR-G Hinged Cover is used,
follow the included installation instructions. See Figs 6
and 7.
All connections to the SE-330HV are made with plugin, wire-clamping terminal blocks. Each plug-in terminal
block can be secured to the monitor by two captive screws
for reliable connections.
Outline dimensions and mounting details for surface
mounting the SE-330HV are shown in Fig. 5. Fasten the
surface-mount adapter to the mounting surface and make
connections to the adapter terminal blocks. Follow Fig. 5
instructions to mount or remove the SE-330HV.
Ground terminal 7 (G) and connect terminal 6 (R) to
the sensing-resistor R terminal.
Use terminal 1 (L1) as the line terminal on ac systems,
or the positive terminal on dc systems. Use terminal 2
(L2/N) as the neutral terminal on ac systems or the
negative terminal on dc systems. Connect terminal
3 ( ) to ground. Connect terminal 4 (SPG) to terminal
5 (SPGA). Remove the terminal-4-to-5 connection for
dielectric-strength testing.
Page 5
Rev. 4-A-112913
NOTE: When the terminal-4-to-5 connection is removed,
protective circuits inside the SE-330HV are disconnected
to allow dielectric strength testing of a control panel
without having to disconnect wiring to the SE-330HV.
Ensure that the terminal-4-to-5 connection is replaced
after testing.
3.2 SENSING RESISTOR
Outline and mounting details for ER-15KV, ER-25KV,
ER-35KV and ER-72KV sensing resistors are shown in
Figs. 8, 9, 10, 11 and 12. Locate the NGR and the sensing
resistor near the transformer or generator. When located
outdoors, a sensing resistor must be installed in a suitable
enclosure. Ground sensing-resistor terminal G. Pass the
sensing-resistor-to-neutral conductor and the NGR-toneutral conductor through the ground-fault-CT window as
shown in Fig. 3. Separately connect sensing-resistor
terminal N and the NGR to the neutral to include neutral
connections in the monitored loop. Alternately, if the NGR
connection to system neutral need not be monitored,
connect terminal N to the NGR neutral terminal. If a
ground fault in the sensing-resistor conductor is unlikely, a
minimal loss of protection will result if it does not pass
through the ground-fault-CT window. See Note 3 in Fig. 3.
Outline and mounting details for the ER-1000HV
Sensing Resistor are shown in Fig. 13. This sensing resistor
can be used to monitor a low-voltage very-high-resistance
NGR. See the simplified diagram in Fig. 14.
CAUTION: Voltage at terminal N rises to line-to-neutral
voltage when a ground fault occurs. The same clearances
are required for sensing resistors as for NGR’s.
NOTE: A parallel ground path created by moisture can
result in a false resistor-fault trip. Sensing-resistor
terminal R and its connection to SE-330HV terminal R,
including interposing terminal blocks, must remain dry.
NOTE: The neutral-to-sensing-resistor-terminal-N connection
is not a neutral conductor as defined in Canadian
Electrical Code Section 10-1108 and National Electrical
Code Section 250.36(B). It is not required to be 8 AWG
or larger. Since current through this conductor is always
less than 250 mA, a 14 AWG conductor insulated to the
system voltage is more than sufficient.
Page 6
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
TRANSFORMER
OR GENERATOR
NOTE 1
NOTE 12
XXX:1 OR
NOTE 2
NOTES 12 & 13
XXX:5
EFCT-X
OR
SE-CS30-X
NOTE 3
N
8
S
9
1
11
10
5
8
C
S
9
ER-SERIES
SENSING
RESISTOR
10 11
5
1
NOTE 4
R
G
1
NOTE 7
L2/N
L1
K1
22
6
K3
28
K4
REMOTE
RESET
16
17
NC
UNIT HEALTHY
NOTE 8 +24V
18
+
19
-
20
ANALOG OUTPUT
RESET
0V
DCD
DSR
5
RESISTOR
FAULT
21
NOTE 9
SELF POWERED
4-20 mA
OUTPUT
NC
3
4
GROUND
FAULT
13
12
15
C
27
RF
NOTE 15
NOTE 14 & 15
24
25
14
NOTE 6
N/- SUPPLY
2
GF
29
NOTE 5
7
23
K2
26
SPG
G
R
ALTERNATE CT
CONNECTIONS
L/+ SUPPLY
NGR
C
5A
1A
EFCT
SE-330HV
NEUTRAL
CTS
SPGA
1
6
8
5
RxD
TxD
OPTIONAL
NETWORK COM
NOTE 11
2
3
RS232 COM
NOTE 10
NOTES:
1. USE SEPARATE LUG TO CONNECT SENSINGRESISTOR TERMINAL N TO NEUTRAL.
2. LOCATE THESE COMPONENTS NEAR
TRANSFORMER OR GENERATOR.
3. ALTERNATE SENSING-RESISTOR TERMINAL-N
CONNECTION. THE NEUTRAL CONNECTION
IS NOT MONITORED.
4. VOLTAGE BETWEEN SENSING-RESISTOR
TERMINALS R AND G IS LIMITED TO 100 V BY
INTERNAL CLAMP.
5. ALTERNATE CT LOCATION. NGR MUST ONLY
BE GROUNDED AT ONE POINT AS SHOWN.
6. SEE SECTION 3.4 FOR ISOLATED-EARTH
CONNECTION.
7. RELAY CONTACTS SHOWN WITH SE-330HV
DE-ENERGIZED.
8. OPTIONAL N.C. AVAILABLE.
9. LOOP-POWERED CONNECTION USES
TERMINALS 19 AND 20 ONLY.
10. RS-232 PIN 4 (DTR), PIN 7 (RTS) AND PIN 9 (RI)
NOT CONNECTED.
11. REFER TO APPROPRIATE SE-330
COMMUNICATIONS INTERFACE MANUAL.
12. TWO-CONDUCTOR TWISTED CABLE
REQUIRED. SHIELDED OR ARMOURED
RECOMMENDED.
13. CT CONNECTION IS NOT POLARITY
SENSITIVE.
14. CONNECT CONTACTS K1, K2, K3, AND K4
AS REQUIRED FOR PROTECTION,
INDICATION, AND CONTROL.
SE-330HV
FIGURE 3. SE-330HV Connection Diagram.
15. EXTERNAL LIGHTS AND SWITCHES NOT
INCLUDED WITH SE-330HV.
Page 7
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
132.0
(5.20)
16.0
(0.63)
98.3
PANEL THICKNESS
1.6 (0.06) TO 4.8 (0.19)
(3.87)
LITTELFUSE STARTCO
NEUTRAL-GROUNDING-RESISTOR SE-330HV
MONITOR
GROUND
FAULT
RESISTOR
FAULT
DIAGNOSTIC
TRIP
1
2
3
4
5
CALIBRATED
20
40
60
4
80
2
100
GF TRIP LEVEL
(% CT RATING)
0.5 0.7 1.0
0.4
0.3
0.2
0.1
POWER
1000
1700
4000
6000
300
8500
100
10000
VN TRIP LEVEL
(S5
(S5
2.0
3.0
5.0
10.0
GF TRIP TIME (s)
850
650
500
200 K Ω VN x 2)
100 K Ω VN x 1)
CAL
185.4
15
212.6
(8.37)
10
(7.30)
RELAY K1
8
6
12
13
NC - 14
15
RESET
16
17
+ 24V - 18
+ - 19
ANALOG OUTPUT
- - 20
0V - 2 1
UNIT
HEALTHY K4
TRIP
-
L1
L2/N
SPG
SPGA
ATTENTION
DISENGAGE CAPTIVE RETAINING
S C R E W S BE F O R E R E M O V I N G
P L U G -I N T ER M I NA L B L O CK S
1
6 - R
7 - G
2
3
4
5
6
SENSING
RESISTOR
K1
22
23
7
8
8 9 10 11-
RESET
SIDE VIEW
FRONT VIEW
NOTE 2
8.2
(0.32)
S
E
1
F
5 5 A1 C
T
C A
GROUND
FAULT
K2
RESISTOR
FAULT
K3
24
25
26
27
28
29
REAR VIEW
92.7
(3.65)
76.2
(3.00)
186.0
(7.32)
200.0
(7.87)
NOTES:
4.75 (0.187) DIA
4 LOCATIONS
7.0
(0.28)
R=4.8 (0.19)
MAXIMUM
PANEL-MOUNT CUTOUT
FIGURE 4. SE-330HV Outline and Panel-Mounting Details.
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. SE-330HV SHOWN WITHOUT SWITCH
ACCESS COVER.
Page 8
Rev. 4-A-112913
8.0
(0.31)
6.4
RETAINER SCREW
RETAINER
114.3
(4.50)
98.3
(3.87)
(0.25)
SE-330HV Neutral-Grounding-Resistor Monitor
138.0
(5.43)
LITTELFUSE STARTCO
NEUTRAL-GROUNDING-RESISTOR SE-330HV
MONITOR
GROUND
FAULT
RESISTOR
FAULT
DIAGNOSTIC
TRIP
L1 - 1
L2/N - 2
- 3
SPG - 4
SPGA - 5
RELAY K1
10
15
20
40
60
4
80
2
100
GF TRIP LEVEL
(% CT RATING)
0.7
0.5
1.0
SENSING
RESISTOR
0.4
0.3
0.2
0.1
R - 6
G - 7
2.0
3.0
5.0
10.0
POWER
S - 8
E
1 - 9
F
C 1
T A 5 5 -1 0
A C -1 1
(S5
(S5
FRONT VIEW
SE-330-SMA
25.4
(1.00)
200 K Ω VN x 2)
100 K Ω VN x 1)
1
2
6
7
3
4
5
6
7
8
8
9
10
11
RESET
FRONT VIEW
63.5
(2.50)
5.0
RESISTOR
FAULT
K3
1000
1700
4000
6000
CAL
GF TRIP TIME (s)
GROUND
FAULT
K2
850
650
500
300
8500
100
10000
VN TRIP LEVEL
(0.20)
24
25
26
27
28
29
K1
1
2
3
4
5
CALIBRATED
8
6
22
23
TRIP
212.6
(8.37)
225.4
(8.87)
12
NIT
K4 U
HEALTHY
13
14 - NC
15
RESET
16
PULSE ENABLE
17
18 - + 24V
19- +
ANALOG OUTPUT
20 - 2 1 - 0V
SIDE VIEW
NOTES:
1. DIMENSIONS IN MIILLIMETRES (INCHES).
(NOTE 2)
2. MOUNTING SCREWS: M4 OR 8-32 PANHEAD.
MONITOR INSTALLATION
215.9
(8.50)
1. LOOSEN RETAINER SCREWS, MOVE RETAINERS
OUT WARD, AND TIGHTEN RETAINER SCREWS.
2. MATE MONITOR WITH ADAPTER PLUG-IN TERMINALS.
LOOSEN RETAINER SCREWS TO LET RETAINERS
SNAP OVER MONITOR BACKPLATE.
3. ENSURE THAT RETAINERS ARE AGAINST MONITOR
BODY AND TIGHTEN RETAINER SCREWS.
MONITOR REMOVAL
1. LOOSEN RETAINER SCREWS, SLIDE RETAINERS AWAY
FROM MONITOR BODY AND TIGHTEN RETAINER SCREWS.
BEZEL OUTLINE
2. PULL MONITOR FORWARD.
ADAPTER PANEL OUTLINE
MOUNTING DETAIL
FIGURE 5. SE-330HV Outline and Surface-Mounting Details.
Page 9
Rev. 4-A-112913
TO PREVENT UNAUTHORIZED ENTRY:
(1.34)
34.0
SE-330HV Neutral-Grounding-Resistor Monitor
1. USE WIRE SEAL THROUGH HOLES IN
WEATHERPROOF COVER ASSEMBLY, OR
2. SECURE WITH THE PLASTIC THREAD FORMING
SCREW SUPPLIED IN KIT.
SHOWN
WITH
SEAL
(9.84)
250.0
TOP VIEW
HOLE FOR
SEAL WIRE
127.0
(5.00)
FRONT VIEW
NOTES:
1. DIMENSIONS SHOWN IN MILLIMETRES (INCHES).
2. SHOWN WITH WEATHERPROOF SNAPS CLOSED.
3. REFER TO PANEL MOUNTING CUTOUT (FIGURE 4) FOR PANEL
MOUNTING DETAIL.
FIGURE 6. SE-IP65CVR-G Weatherproof Cover Outline.
SIDE VIEW
Page 10
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
INSTALL O-RING INTO
GROOVE IN THE REAR
OF WEATHERPROOF
WINDOW
INSERT THE SE-330HV THROUGH OPENING
OF THE WEATHERPROOF WINDOW, UNTIL IT
IS SECURELY NESTED TO THE BACK OF THE
DARK GREY PVC PANEL.
FRONT-PANEL
DETAILS NOT SHOWN.
INSTALL O-RING INTO THE GROOVE IN THE REAR
OF WEATHERPROOF WINDOW ASSEMBLY.
INSERT ASSEMBLY INTO PANEL AND FASTEN WITH
THE HARDWARE PROVIDED WITH THE SE-330HV.
FIGURE 7. SE-IP65CVR-G Weatherproof Cover Installation.
Page 11
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
422.0
RATINGS:
E R - 1 5 KV
SENS IN G RESISTO R
R
1 0 0 KΩ
84 0 0 V A C M A X
1 M I N UT E M A X
CAUTION
HIGH VOLTAGE
132.0
(5.20)
144.0
(5.67)
(16.61)
N
VOLTAGE AT TERMINAL N RISES
TO LINE-TO-NEUTRAL VOLTAGE
WHEN A GROUND FAULT OCCURS
G
MAXIMUM VOLTAGE . . 8,400 Vac
MAXIMUM CURRENT . 84 mA
RESISTANCE . . . . . . . . 100 kΩ
THERMAL
8,400 Vac . . . . . . . . . . 1 MINUTE ON,
120 MINUTES
OFF
.
.
.
.
.
.
.
.
.
.
CONTINUOUS
1,900 Vac
NOTES 2 AND 4
0.25-20 BINDING HEAD
215.0
(8.46)
TOP
20.5
(0.81)
TORQUE
TERMINAL N . . . . . . . . 9.0 N-m (80 in-lb)
SIDE
FRONT
444.0
(17.50)
365.0
(14.37)
90.0
(3.53)
39.5
(1.56)
MINIMUM DISTANCE
TO ADJACENT OBJECTS
39.5
(1.56)
NOTES:
90.0
2. TERMINAL-BLOCK SCREWS:
6-32 x 0.25.
NOTE 3
MINIMUM CLEARANCE FROM BASE
305.0 (12.00)
3. MOUNTING SCREWS:
M6 OR 0.25-20.
4. USE LIQUID-TIGHT FITTING
FOR TERMINAL-BLOCKENCLOSURE CABLE ENTRY.
(3.53)
280.0
(11.00)
100.0
(3.94)
1. DIMENSIONS IN MILLIMETRES
(INCHES).
5. CERTIFICATIONS NOT SHOWN.
MOUNTING DETAIL
FIGURE 8. ER-15KV Sensing Resistor.
Page 12
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
780.0
(30.70)
100 K Ω
1 4,4 00 V A C MA X
1 M I N UT E MA X
R
N
0.25-20 BINDING HEAD
NOTES 2 AND 4
20.5
V O L T A G E A T T E R M I N A L N R I SE S
TO LI NE-TO -N EUTRAL VO LT AGE
WHEN A GR OUND FAULT O CCURS
G
(0.81)
144.0
(5.67)
RATINGS:
CAUTION
CAUTION
HIGH
H I G HVOLTAGE
VOLTAGE
E R - 2 5 KV
SE NS I NG R ES I ST OR
320.0
(12.60)
TOP
MAXIMUM VOLTAGE . 14,400 Vac
MAXIMUM CURRENT. 144 mA
RESISTANCE . . . . . . . 100 kΩ
THERMAL
14,400 Vac . . . . . . . . . 1 MINUTE ON,
120 MINUTES
OFF
2,500 Vac . . . . . . . . . CONTINUOUS
TORQUE
TERMINAL N . . . . . . . 9.0 N-m (80 in-lb)
FRONT
60.0
(2.40)
800.0
(31.50)
340.0
(13.38)
SIDE
340.0
(13.38)
217.0
(8.50)
534.0
(21.00)
100.0
(3.94)
NOTES:
1. DIMENSIONS IN
MILLIMETRES (INCHES).
NOTE 3
2. TERMINAL-BLOCK SCREWS:
6-32 x 0.25.
MINIMUM CLEARANCE FROM BASE
508.0 (20.00)
MINIMUM DISTANCE
TO ADJACENT OBJECTS
3. MOUNTING SCREWS:
M6 OR 0.25-20
4. USE LIQUID-TIGHT FITTING
FOR TERMINAL-BLOCKENCLOSURE CABLE ENTRY.
5. MOUNT AS SHOWN
WITH BASE HORIZONTAL.
6. CERTIFICATIONS NOT SHOWN.
MOUNTING DETAIL
FIGURE 9. ER-25KV Sensing Resistor.
Page 13
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
20.5
132.0
(5.20)
1000.0
(39.40)
CAUTION
HIGH VOLTAGE
E R - 3 5 KV
S E N SIN G R E SIS TO R
R
10 0 K Ω
22 , 2 0 0 V AC MA X
1 M I N UT E M AX
N
V OLTA GE AT TE RM INAL N RIS ES
TO LINE- TO- NEUT R AL V OLTA GE
W HEN A G ROUN D F AULT OCC URS
G
(0.81)
RATINGS:
MAXIMUM VOLTAGE . 22,000 Vac
MAXIMUM CURRENT . 220 mA
RESISTANCE . . . . . . . 100 kΩ
THERMAL
22,000 Vac . . . . . . . . . 1 MINUTE ON,
120 MINUTES
OFF
3,000 Vac . . . . . . . . . . CONTINUOUS
TORQUE
TERMINAL N . . . . . . . 9.0 N-m (80 in-lb)
0.25-20 BINDING HEAD
NOTES 2 AND 4
459.0
(18.10)
TOP
FRONT
SIDE
1600.0
(63.00)
MINIMUM CLEARANCE FROM BASE
685.0 (27.00)
100.0
(3.90)
400.0
(15.70)
400.0
(15.70)
NOTE 3
350.0
(13.80)
800.0
(31.50)
350.0
(13.80)
MINIMUM DISTANCE
TO ADJACENT OBJECTS
MOUNTING DETAIL
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS: 6-32 x 0.25.
3. MOUNTING SCREWS: M6 OR 0.25-20.
4. USE LIQUID-TIGHT FITTING FOR
TERMINAL-BLOCK-ENCLOSURE CABLE ENTRY.
5. MOUNT AS SHOWN WITH BASE HORIZONTAL.
6. CERTIFICATIONS NOT SHOWN.
FIGURE 10. ER-35KV Sensing Resistor.
Page 14
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
1044.9
(41.14)
RATINGS:
E R -7 2 KV
CA UTI O N
HI GH VOLTA GE
TERMINAL N
0.25-20 BINDING
HEAD
(7.42)
188.6
N
V O L T AG E AT T E R M IN AL N R I S E S
T O L I N E - T O -N E UT R AL V O L T A G E
WH E N A G R O U N D F A UL T O C CU R S
200 K
4 4 , 4 00 V A C M A X
1 M I N UT E M A X
SENSING RESISTOR
1181.1
(46.50)
MAXIMUM VOLTAGE . 44,000 Vac
MAXIMUM CURRENT. 220 mA
RESISTANCE . . . . . . . 200 kΩ
THERMAL
44,000 Vac. . . . . . . . . 1 MINUTE ON,
120 MINUTES
OFF
6,000 Vac . . . . . . . . . CONTINUOUS
TORQUE
TERMINAL N . . . . . . . 9.0 N-m (80 in-lb)
863.6
(34.00)
457.0
(17.99)
908.0
(35.75)
TOP
FRONT
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS: 6-32 x 0.25.
3. MOUNTING SCREWS: M6 OR 0.25-20.
4. USE LIQUID-TIGHT FITTING FOR
TERMINAL-BLOCK-ENCLOSURE CABLE ENTRY.
FIGURE 11. ER-72KV Sensing Resistor Outline.
RIGHT SIDE
Page 15
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
247.7
514.4
247.7
(9.75)
(20.25)
(9.75)
(5.50)
ER-72KV ORIENTED
WITH TERMINAL N
IN THIS LOCATION
140.0
247.7
432.0
(17.00)
MINIMUM
DISTANCE
TO ADJACENT
OBJECTS
(9.75)
2286.0
(90.00)
432.0
(17.00)
247.7
432.0
(17.00)
(9.75)
432.0
(17.00)
650.7
73.0
(2.88)
(25.63)
365.0
(14.38)
1146.0
(45.13)
2133.6
(84.00)
1009.7
355.5
(39.75)
(14.00)
775.0
(30.50)
768.4
(30.25)
MINIMUM VERTICAL
CLEARANCE FROM BASE: 1800.0 (70.87)
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M6 OR 0.25-20.
FIGURE 12. ER-72KV Sensing Resistor Mounting Details.
Page 16
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
RATINGS:
MAXIMUM VOLTAGE . 600 Vac
MAXIMUM CURRENT. 3 mA
RESISTANCE . . . . . . . 200 kΩ
THERMAL . . . . . . . . . . CONTINUOUS
41.5
40.0
(1.63)
(1.57)
10.5
19.0
10.5
(0.41)
(0.75)
(0.41)
8.0
22.2
(0.87)
(0.31)
40.0
(1.57)
NOTE 3
N
89.0
(3.50)
8.0
(0.31)
105.0
(4.13)
105.0
G
(4.13)
R
ER-1000HV
SENSI NG RES I STOR
20 0 K Ω
6 0 0 VA C M A X
4.5 (0.18) DIA
C’BORE 10.0 (0.39) DIA
3.2 (0.13) DEEP
FRONT
SIDE
NOTES:
1.
DIMENSIONS IN MILLIMETRES (INCHES).
2. TERMINAL-BLOCK SCREWS: 6-32 x 0.25.
3.
MOUNTING SCREWS: M4 OR 8-32.
4.
ENCLOSURE IS ELECTRICALLY CONNECTED TO TERMINAL G
THROUGH JUMPER FROM TERMINAL G TO
SCREW.
THIS CONNECTION MAY BE REMOVED FOR DIELECTRIC STRENGTH
TESTING. ENSURE THAT THE JUMPER IS INSTALLED AFTER TESTING.
FIGURE 13. ER-1000HV Sensing Resistor
MOUNTING DETAIL
SE-330HV Neutral-Grounding-Resistor Monitor
Page 17
Rev. 4-A-112913
NEUTRAL
NGR
NOTE 1
8 9
S
1
ER-1000HV
SENSING
RESISTOR
10 11
5
C
5A
1A
EFCT
R
R
3
4
SPG
5
SPGA
N
G
G
6
7
NOTES:
L1
SE-330HV
L2/N
1
2
L/+ SUPPLY
N/- SUPPLY
1. GF TRIP SETTING IS PERCENT OF 50 mA
WHEN NO CT IS USED.
2. FOR GF SETTING > 50 mA USE EFCT-x.
MULTIPLE PRIMARY WRAPS MIGHT
BE REQUIRED.
FIGURE 14. ER-1000HV Simplified Connection Diagram.
3.3 GROUND-FAULT CT
Select and install a ground-fault CT that will provide
the desired trip level. Typically, the CT-primary rating
should approximately equal the NGR let-through-current
rating. This provides an appropriate GF TRIP LEVEL
setting range and analog-output scaling. See Sections
2.1.2 and 2.8.
Outline and mounting details for the EFCT- and
SE-CS30-series current sensors are shown in Figs. 15,
16, and 17. Ground-fault-CT connections and the
preferred ground-fault-CT location are shown in
Fig. 3. If a ground fault in the NGR is unlikely, a
minimal loss of protection will result if the ground-fault
CT monitors the NGR connection to ground rather than
its connection to neutral. A minimal loss of protection
will also result if the sensing-resistor-to-neutral
connection does not pass through the CT window. This
alternate CT location is shown in Fig. 3.
The accuracy of a typical current transformer
decreases below 5% of its current rating. CT-primary
current injection testing is recommended to verify trip
levels below 5% of the CT-primary rating.
See
Section 9.4. Littelfuse Startco current sensors are
designed for use at low levels and respond linearly to 2%
current rating.
NOTE: The current-transformer insulation class is of no
consequence if its secondary is grounded and the
conductors through its window are insulated for the
system voltage. Bushing type CT’s are required for
applications using bare conductors on the NGR’s neutral
side.
Page 18
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. MOUNTING SCREWS: M4 OR 8-32.
P1
Ground Fault Sensing
and Relaying Equipment
4FX9 E340889
3. PRESS MOUNTING FEET IN PLACE USING
INSTALLATION TOOL PROVIDED.
®
S1
S2
4. RoHS COMPLIANT.
5. EN 60044-1 COMPLIANT.
121.0
(4.76)
121.0
(4.76)
20.5
(0.81)
56.0
(2.21)
46.0
(1.81)
30.0
(1.18)
80.0
(3.15)
NOTE 2
M5 SCREWS
TOP
MOUNTING DETAIL
25.0
(0.98)
30.0
(1.18)
EFCT-1 EARTH FA ULT CT
600 V CLASS, INSULATION CLASS A
R
R
LR 53428
5.0 (0.20) Ø
RECESSED FOR
8-mm HEX NUT
1.0 (0.04) DEEP
22.0
(0.87)
EFCT - 1FC
FLUX
CONDITIONER
(OPTIONAL)
.0
82 23)
.
(3
69
(2.7 .8
5)
126.0
(4.96)
US
(5.43)
138.0 MAX
C
5.5
(0.22)
110.0
(4.33)
FRONT
FIGURE 15. EFCT-1 Ground-Fault Current Sensor.
5.5
(0.22)
56.0
(2.21)
SIDE
Page 19
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
P1
Ground Fault Sensing
and Relaying Equipment
4FX9 E340889
®
S1
121.0
(4.76)
S2
121.0
(4.76)
20.5
80.0
(3.15)
56.0
(2.21)
46.0
(1.81)
30.0
(1.18)
(0.81)
NOTE 3
M5 SCREWS
TOP
MOUNTING DETAIL
25.0
(0.98)
(1.18)
30.0
SE-CS30-70
CURRENT SENSOR
R
R
LR 53428
22.0
Ø 5.0 (0.20)
RECESSED FOR
8-mm HEX NUT
1.0 (0.04) DEEP
5.5
110.0
5.5
(0.22)
(4.33)
(0.22)
56.0
(2.21)
SIDE
FRONT
MOUNTING FOOT
INSTALLATION
TOOL
126.0
69.
8
(2.7
5)
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. PRESS MOUNTING FEET IN PLACE USING
INSTALLATION TOOL PROVIDED (DETAIL ‘A’).
3. MOUNTING SCREWS: M4 OR 8-32.
DETAIL ‘A’
FIGURE 16. SE-CS30-70 Ground-Fault Current Sensor.
(4.96)
US
(0.87)
(5.43)
138.0 MAX
C
4. RoHS COMPLIANT.
5. EN 60044-1 COMPLIANT.
Page 20
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
P1
Ground Fault Sensing
and Relaying Equipment
4FX9 E340889
®
S1
68.0
(2.68)
34.0
(1.34)
S2
68.0
(2.68)
M4 OR 8-32 TAP
26.5
(1.04)
52.5
(2.07)
42.6
(1.68)
17.0
(0.67)
MOUNTING DETAIL
TOP
(0.43)
110.0 MAX
M5 SCREWS
25.0
(0.98)
26.5
(1.04)
SE-CS30-26
CURRENT SENSOR
R
R
LR 53428
US
4.0 (0.16) Ø
0
.
26
RECESSED FOR
7-mm HEX NUT
3.0 (0.12) DEEP
2)
7.0
.0
(1
58.0
(2.28)
(0.87)
34.0
(1.34)
72.0
(2.83)
C
5.0
(0.20)
5.0
(0.20)
52.5
(2.07)
FRONT
SIDE
NOTES:
1. DIMENSIONS IN MILLIMETRES (INCHES).
2. PRESS MOUNTING FEET IN PLACE USING
INSTALLATION TOOL PROVIDED (DETAIL ‘A’).
MOUNTING FOOT
INSTALLA TION
TOOL
3. MOUNTING SCREWS: M4 OR 8-32.
4. RoHS COMPLIANT.
5. EN 60044-1 COMPLIANT.
DETAIL ‘A’
6. SE-CS30-26 SHOWN.
FIGURE 17. EFCT-26 and SE-CS30-26 Ground-Fault Current Sensors.
Page 21
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
30.0
(1.18)
RESISTOR FAULT
17.3
(0.68)
36.6
(1.44)
29.9
(1.17)
NOTE 4
22.2 (0.87) DIA
NOTES:
LEGEND PLATES
1. TWO RED LED LIGHTS
24-120 VAC/DC, NOT POLARITY
SENSITIVE.
30.0 MINIMUM
(1.18)
2. YELLOW PUSH BUTTON
3 A @ 240 VAC - A600,
0.5 A @ 125 VDC - Q600.
(1.57)
40.0 MINIMUM
43.5
36.6
(1.44)
(1.71)
PILOT LIGHTS
14.9
(0.59)
3. DIMENSIONS IN MILLIMETRES
(INCHES).
4. ----- INDICATES CLEARANCE
REQUIRED.
29.9
(1.17)
PUSH BUTTON
GROUND FAULT
LEGEND
PLATE
(0.59)
22.5
(0.89)
15.0
X1
X2
43.5
(1.71)
25.0
(0.98)
RESET
5. PANEL THICKNESS 1.0 TO 6.0
(0.04 TO 0.24).
MOUNTING DETAIL
6. NEMA 4X.
FIGURE 18. RK-332 Remote Indication and Reset.
3.4 ISOLATED GROUND CONNECTION
An isolated ground bed can prevent a ground potential
rise (GPR) from being transferred to remote equipment.
If the G terminals on the sensing resistor and the
SE-330HV are connected to an isolated ground, the
SE-330HV will be exposed to the GPR. If the GPR is
greater than the terminal-block rating, the SE-330HV
must be isolated from station ground and precautions
must be taken with the power supply and the trip contacts.
See Technical Note RG-1 “NGR Monitoring with Isolated
Ground Beds” at www.littelfuse.com/protectionrelays.
An alternate configuration which allows an SE-330HV
to be connected to station ground is shown in Fig. 19.
The SE-330HV monitors the series combination of the
NGR and the two ground beds. This configuration is
acceptable provided the series resistance of the NGR and
the ground beds is within the NGR calibration range and
ground-bed-resistance changes remain within the trip
range. See Section 6.1.
NEUTRAL
ER-SERIES N
SENSING
RESISTOR
STATION
TRIP CIRCUIT
22
NGR
23
R
STATION
CONTROL
SUPPLY
1
2
K1
L1
R
L2/N
G
G
6
7
SE-330HV
3
STATION GROUND BUS
STATION
GROUND BED
ISOLATED
GROUND BED
REMOTE GROUND
FIGURE 19. Simplified Isolated-Ground Connection.
SE-330HV Neutral-Grounding-Resistor Monitor
4. COMMUNICATIONS
4.1 LOCAL COMMUNICATION PORT
The SE-330HV has an RS-232 local communications
port which is designed for use with firmware-upgrade
and system-monitoring software running on a PC.
The RS-232 port is non-isolated and operates as a
DCE device with the connector (socket contacts) pin-out
listed in Table 3. This port allows direct connection to a
PC using standard DB-9 connector cables. Cable length
should not exceed 10 metres.
PIN #
1
2
3
4
5
6
7
8
9
TABLE 3. RS-232 DB-9 TERMINALS
SIGNAL
COMMENTS
NAME
DCD
RD
TD
DTR
SG
DSR
RTS
CTS
RI
470  connected to +12 V
Output to DTE from SE-330HV
Input from DTE to SE-330HV
Not connected
Signal Ground
470  connected to +12 V
Not connected
470  connected to +12 V
Not connected
4.1.1 LOCAL DATA ACQUISITION
The SE-330HV outputs a data packet every second.
Data output is in the standard UART data format of eight
data bits and one stop bit. The baud rate is fixed at
38,400 bits per second. Use PC program SE-MON330 to
display the following data:
 SE-330HV settings and switch states.
 Neutral voltage and current.
 Resistance change.
 Trip status.
 Pending trips.
 Relay and LED status.
 NGR calibration value.
- Expected 100-k value: RNGR to (RNGR-4,000)
- Expected 200-k value: RNGR to (RNGR-8,000)
 Firmware revision level.
 The last ten trip records. Each record contains the trip
cause and the pre-trip NGR current, voltage, and
resistance values.
Data can be logged to a PC file at user-defined time
intervals for future analysis.
Page 22
Rev. 4-A-112913
4.1.2 LOCAL COMMUNICATIONS COMMANDS
As of firmware revision 10, the SE-330HV supports
basic commands through the local RS-232
communications port. Commands are input as standard
ASCII characters. The latest revision of SE-MON330
supports the following commands:
‘d’ – Read event records.
‘c’ – Clear event records.
4.1.3 FIRMWARE UPGRADE
The local port can be used to upgrade the SE-330HV
firmware. Upgrade procedure:
1) Remove supply voltage.
2) Set switch S8 to UPGRADE.
3) Apply supply voltage. The DIAGNOSTIC LED
will be on and all relays will be de-energized.
4) Run SE-FLASH and follow the instructions.
5) Remove supply voltage.
6) Set switch S8 to RUN.
7) Apply supply voltage.
SE-MON330 and SE-FLASH are available
www.littelfuse.com/protectionrelays.
at
4.2 NETWORK COMMUNICATIONS
The SE-330HV interface for optional communications
modules supports DeviceNet™, PROFIBUS®, and
Ethernet:
DeviceNet™:
 DeviceNet Slave.
 DeviceNet specification Vol 1:2.0, Vol 2:20.
PROFIBUS®:
 PROFIBUS-DP Slave according to IEC 61158.
Ethernet:
 Modbus TCP Class 0, 1.
 Ethernet/IP Level 2 I/O Server CIP (ControlNet and
DeviceNet)
 WebServer, on-board selection of IP address.
Communications options allow the user to:
 Read SE-330HV settings.
 Read neutral voltage and current.
 Read resistance change.
 Read trip status.
 Reset trips.
 Perform a remote trip.
 Access the last ten trip records. Each trip record
contains the cause of trip and the pre-trip NGR
current, voltage, and resistance values.
 Clear event records.
Refer to the appropriate SE-330 communicationsinterface manual.
Page 23
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
5. TROUBLESHOOTING
PROBLEM
POWER LED off.
POWER LED flashes.
Calibration-Error Trip
DIAGNOSTIC LED flash code = L-S-L...*
Remote Trip
DIAGNOSTIC LED flash code = L-S-S-L…*
EEPROM-Error Trip
DIAGNOSTIC LED flash code = L-S-S-S-L…*
A/D-Converter-Error Trip
DIAGNOSTIC LED flash code = L-S-S-S-S-L…*
Software-Interrupt Trip
DIAGNOSTIC LED flash code = L-S-S-S-S-S-L…*
Illegal-Opcode Trip
DIAGNOSTIC LED flash code = L-S-S-S-S-S-S-L…*
Watchdog Trip
DIAGNOSTIC LED flash code = L-S-S-S-S-S-S-S-L…*
Clock-Failure Trip
DIAGNOSTIC LED flash code = L-S-S-S-S-S-S-S-S-L…*
CPU Trip
DIAGNOSTIC LED flash code = L-S-S-S-S-S-S-S-S-S-L…*
DIAGNOSTIC LED = Solid Red
Pressing RESET does not clear trips.
UNIT HEALTHY relay K4 momentarily changes state.
GROUND-FAULT and RESISTOR-FAULT LED's flash
during reset.
No analog-output current.
*L = long pause, S = short flash.
SOLUTION
Check if supply voltage is present on terminals 1 and 2. If present, an
overvoltage may have caused the power supply to shutdown. Cycle
supply voltage. If POWER LED remains off, return unit for repair.
A power-supply overload has occurred. Cycle supply voltage. If
problem persists, consult Littelfuse Startco.
The total resistance of the NGR and sensing-resistor circuit is outside the
calibration range. Verify that switch S5 is set to match the resistance of
the sensing resistor, check the resistance of the NGR, and verify the
sensing-resistor circuit. See Section 9.2 for sensing-resistor tests.
Repeat the calibration procedure after the open or shorted condition has
been corrected.
The SE-330HV was tripped by a signal from network communications.
Press RESET to clear the trip.
An error was detected in the EEPROM. Press RESET to clear the trip.
If the problem persists, consult Littelfuse Startco.
An A/D-converter error was detected. Press RESET to clear the trip. If
the problem persists, consult Littelfuse Startco.
These four errors result in a processor reset. During reset, UNIT
HEALTHY relay K4 will be de-energized. After a reset, UNIT
HEALTHY relay K4 will be energized. Press RESET to clear the trip.
If the problem persists, consult Littelfuse Startco.
When supply voltage is cycled, the specific error code is lost but the
CPU Trip Code will be displayed.
This code is displayed if the supply is cycled after one of the previous
four errors occurred. Press RESET to clear the trip.
Switch S8 is in the UPGRADE position. If firmware upgrade is not
required, set switch S8 to RUN and cycle supply.
SE-330HV processor failed to start. Cycle supply. Consult Littelfuse
Startco if problem persists.
Trip condition is still present. Locate and correct.
The face-plate RESET button is disabled if remote-reset terminals 15
and 16 are connected. Replace shorted remote-reset switch or issue
Reset command from the communications network.
Occurs when processor is reset.
Normal operation.
The output at terminals 19 and 20 requires a voltage source. See Fig. 2
for analog-output connections. See Section 9.3 for the analog-output
tests.
SE-330HV Neutral-Grounding-Resistor Monitor
6. TECHNICAL SPECIFICATIONS
6.1 SE-330HV
Supply
Option 0 ................................. 30 VA, 120 to 240 Vac
(+10, -45%) 50/60 Hz;
20 W, 110 to 250 Vdc
(+10, -25%)
Option 2 ................................. 20 W, 48 Vdc
(+50, -25%)
35 VA, 48 Vac
(+10, -45%) 50/60 Hz
Power-Up Time ......................... 250 ms at 120 Vac
AC Measurements ..................... Discrete Fourier
Transform. 16 samples
per cycle, 50 or 60 Hz
Resistor-Fault Circuit:
Neutral-To-Ground Voltage Trip Levels:
ER-15KV to ER-35KV ...... 100; 300; 500; 650; 850;
1,000; 1,700; 4,000;
6,000; 8,500; 10,000 Vac
ER-72KV ............................ 200; 600; 1,000; 1,300;
1,700; 2,000; 3,400;
8,000; 12,000; 17,000;
20,000 Vac
Accuracy ............................. 5% of setting
3 dB Frequency Response ..
S6 = 50 Hz ..................... 25-85 Hz
S6 = 60 Hz ..................... 30-90 Hz
NGR Calibration Range:
ER-15KV to ER-35KV ...... 0 to 10 k
ER-72KV ............................ 0 to 20 k
Trip Resistance, VN = 0:
ER-15KV to ER-35KV ...... 2.5-k change ± 1 k
ER-72KV ............................ 5-k change ± 2 k
DC-Voltage Rejection:
ER-15KV to ER-35KV ...... 125 Vdc
ER-72KV ............................ 250 Vdc
Trip Time .................................. 12 ± 1 s
Trip Hold-Off Level................. 5% of CT-Primary Rating
Operating Mode ....................... Latching/Non-Latching
Ground-Fault Circuit:
Trip Level ................................. 2, 4, 6, 8, 10, 15, 20,
40, 60, 80, 100% of
CT-Primary Rating
Trip Time .................................. 0.1, 0.2, 0.3, 0.4, 0.5, 0.7,
1.0, 2.0, 3.0, 5.0, 10.0 s
Trip-Level Accuracy ................ 1% of CT-Primary Rating
Trip-Time Accuracy ................ 10% of Setting
3 dB Frequency Response .......
S6 = 50 Hz........................... 25-85 Hz
S6 = 60 Hz........................... 30-90 Hz
Maximum CT lead resistance:
EFCT & SE-CS30.................... 5 ,
Other CT’s ................................ Consult CT Curve
Page 24
Rev. 4-A-112913
CT-Input Burden:
5-A Input ............................. < 0.01 
1-A Input ............................. < 0.05 
EFCT Input ......................... < 10 
Thermal Withstand:
1-A and 5-A Input:
Continuous ...................... 2 x CT Rating
1-Second.......................... 20 x CT Rating
EFCT Input:
Continuous ...................... 10 x CT Rating
1-Second.......................... 25 x CT Rating
Measurement Range ................ 25 x CT-Primary Rating
Operating Mode ....................... Latching/Non-Latching
Trip Relay K1 Contacts:
Configuration ........................... N.O. (Form A)
Operating Mode ....................... Fail-Safe or Non-Fail-Safe
CSA/UL Contact Ratings ........ 8 A resistive 250 Vac,
5 A resistive 30 Vdc
Supplemental Contact Ratings:
Make/Carry 0.2 s ................ 30 A
Break:
dc ...................................... 75 W resistive,
35 W inductive
(L/R = 0.04)
ac ...................................... 2,000 VA resistive,
1,500 VA inductive
(PF = 0.4)
Subject to maximums of 8 A and 250 V (ac or dc).
GF (K2) and RF (K3) Relay Contacts:
Configuration ........................... N.O. and N.C. (Form C)
Operating Mode ....................... Non-Fail-Safe
CSA/UL Contact Ratings ........ 8 A resistive 250 Vac,
8 A resistive 30 Vdc
Supplemental Contact Ratings:
Make/Carry 0.2s ................. 20 A
Break:
dc ...................................... 50 W resistive,
25 W inductive
(L/R = 0.04)
ac ...................................... 2,000 VA resistive,
1,500 VA inductive
(PF = 0.4)
Subject to maximums of 8 A and 250 V (ac or dc).
Unit Healthy Output K4 (Option 0):
Configuration ........................... N.O. (Form A)
Operating Mode ....................... Closed when Healthy
Ratings...................................... 100 mA, 250 V (ac or dc)
Closed Resistance .................... 30 to 50 
Unit Healthy Output K4 (Option 1):
Configuration ........................... N.C. (Form B)
Operating Mode ....................... Open when Healthy
Ratings...................................... 100 mA, 250 V (ac or dc)
Closed Resistance .................... 25 to 50  maximum
Auto-reset time ............................. 2.8 s maximum
SE-330HV Neutral-Grounding-Resistor Monitor
4–20-mA Analog Output:
Type .......................................... Self Powered and
Loop Powered
Range ........................................ 4 to 22 mA
Loop Voltage ............................ 8 to 36 Vdc
Load .......................................... 500  (maximum with
24-Vdc supply)
Isolation .................................... 120 Vac
Parameter .................................. NGR Current
RS-232 Communications:
Baud Rate ................................. 38.4 kb/s
Protocol..................................... Proprietary
Terminal-Block Ratings ............... 10 A, 300 Vac, 12 AWG
(2.5 mm2)
PWB Conformal Coating ............. MIL-1-46058 qualified,
UL QMJU2 recognized
Mounting Configurations ............. Panel Mount and Surface
Mount
Shipping Weight ........................... 2.0 kg (4.4 lb)
Environment:
Operating Temperature ............ -40 to 60°C
Storage Temperature ................ -55 to 80°C
Humidity ................................... 85% Non-Condensing
Surge Withstand ........................... ANSI/IEEE C37.90.1-1989
(Oscillatory and Fast
Transient)
EMC .............................................. EN 55011:1998
Certification .............................. CSA, Canada and USA
R
C
LR 53428
US
UL Listed
Australia(1)
NOTES:
(1)
See Ordering Information.
Page 25
Rev. 4-A-112913
6.2 SENSING RESISTORS
Environment:
Operating Temperature............ -40 to 60°C (-40 to 140°F)
Storage Temperature................ -55 to 80°C (-67 to 176°F)
ER-15KV:
Maximum Voltage ................ 8,400 Vac
Maximum Current ................. 84 mA
Resistance ............................. 100 k
Thermal:
8,400 Vac ......................... 1 minute on,
120 minutes off
1,900 Vac ......................... Continuous
Torque (Terminal N) ............... 9.0 N-m (80 in-lb)
Shipping Weight ...................... 5.0 kg (11 lb)
ER-25KV:
Maximum Voltage ................ 14,400 Vac
Maximum Current ................. 144 mA
Resistance ............................. 100 k
Thermal:
14,400 Vac ....................... 1 minute on,
120 minutes off
2,500 Vac ......................... Continuous
Torque (Terminal N) ............... 9.0 N-m (80 in-lb)
Shipping Weight ...................... 20 kg (44 lb)
ER-35KV:
Maximum Voltage ................ 22,000 Vac
Maximum Current ................. 220 mA
Resistance ............................. 100 k
Thermal:
22,000 Vac ....................... 1 minute on,
120 minutes off
3,000 Vac ......................... Continuous
Torque (Terminal N) ............... 9.0 N-m (80 in-lb)
Shipping Weight ...................... 40 kg (88 lb)
ER-72KV:
Maximum Voltage ............... 44,000 Vac
Maximum Current ................ 220 mA
Resistance ............................ 200 k
Thermal:
44,000 Vac ...................... 1 minute on,
120 minutes off
6,000 Vac ........................ Continuous
Torque (Terminal N) .............. 9.0 N-m (80 in-lb)
Shipping Weight ..................... 95 kg (210 lb)
ER-1000HV:
Maximum Voltage ............... 600 Vac
Maximum Current ................ 3 mA
Resistance ............................ 200 k
Thermal ................................... 600 Vac Continuous
Shipping Weight ..................... 300 g (0.7 lb)
Page 26
Rev. 4-A-112913
SE-330HV Neutral-Grounding-Resistor Monitor
Certification.............................. CSA, Canada and USA
R
C
LR 53428
US
UL Listed
CE, European Union(1)
NOTES:
(1)
CE certification for the ER-72KV is not available.
6.3 CURRENT SENSORS
Environment:
Operating Temperature ...........-40 to 60°C (-40 to 140°F)
Storage Temperature ...............-55 to 80°C (-67 to 176°F)
EFCT-1:
Current Ratio ........................ 5:0.05 A
Insulation .............................. 600-V Class
Window Diameter ................ 82 mm (3.2")
Shipping Weight................... 0.9 kg (2.0 lb)
Certifications ........................ CSA, UL, CE
Compliance .......................... RoHS, IEC 60044-1
Extended Operating
Temperature ............................-55 to 60°C (-67 to
140°F)(1)
Supplemental
Specifications:
Trip Level Accuracy:
≤ 1 A ....................1% of CT-Primary Rating
> 1 A ....................3% of CT-Primary Rating
EFCT-26:
Current Ratio ........................ 5:0.05 A
Insulation .............................. 600-V Class
Window Diameter ................ 26 mm (1.0")
Shipping Weight ................... 0.45 kg (1.0 lb)
Certifications ........................ CSA, UL, CE
Compliance .......................... RoHS, IEC 60044-1
Extended Operating
Temperature ............................-55 to 60°C (-67 to
140°F)(1)
Supplemental
Specifications:
Trip Level Accuracy:
≤ 1 A ..................... 1% of CT-Primary Rating
> 1 A ..................... 3% of CT-Primary Rating
SE-CS10-2.5:
Current Ratio ......................... 1,000:5 A
Insulation ............................... 600-V Class
Window Diameter ................. 63 mm (2.5”)
Shipping Weight.................... 0.7 kg (1.5 lb)
Certifications ......................... CE
Compliance ........................... IEC 60044-1
SE-CS30-26:
Current Ratio ........................30:0.05 A
Insulation .............................600-V Class
Window Diameter ................26 mm (1.0”)
Shipping Weight ..................0.45 kg (1.0 lb)
Certifications ........................CSA, UL, CE
Compliance ..........................RoHS, IEC 60044-1
SE-CS30-70:
Current Ratio ........................30:0.05 A
Insulation .............................600-V Class
Window Diameter ................70 mm (2.7”)
Shipping Weight ..................1.2 kg (2.5 lb)
Certifications ........................CSA, UL, CE
Compliance ..........................RoHS, IEC 60044-1
CT200:
Current Ratio ........................200:5 A
Insulation .............................600-V Class
Window Diameter ................56 mm (2.2”)
Shipping Weight ..................1 kg (2.2 lb)
Certifications ........................CSA, UL
Compliance ..........................RoHS
NOTES:
(1)
Electrical specifications have been verified at a Littelfuse
lab.
7. ORDERING INFORMATION
SE-330HV-
-
K4 Contact:
0 N.O. UNIT HEALTHY Contact
1 N.C. UNIT HEALTHY Contact
Options:
0 No Options
1 C-Tick Compliance
Network Communications
0 None
1 DeviceNet™
2 PROFIBUS®
3 Ethernet
Supply:
0 Universal ac/dc Supply
2 48 V
NOTE: Please refer to the SE-330 Product Change Notice
(PCN) document for updated ordering information and new
revision details, available at www.littelfuse.com/se-330hv.
NOTE: Each SE-330 includes an SE-330-SMA Surface
Mount Adapter.
SE-330HV Neutral-Grounding-Resistor Monitor
Sensing Resistors:
ER-15KV ................................ For system voltages up to
15 kVac
ER-25KV ................................ For system voltages up to
25 kVac
ER-35KV ................................ For system voltages up to
35 kVac
ER-72KV ................................ For system voltages up to
72 kVac
ER-1000HV............................ For system voltages up to
1 kVac
Current Transformers:
EFCT-1 ................................... Ground-Fault CT, 5-Aprimary rating,
82-mm (3.2") window, 6m
(19.5’) of 22 AWG
shielded cable included
EFCT-26 ................................. Ground-Fault CT,
5-A-primary rating,
26-mm (1.0”) window,
6m (19.5’) of 22 AWG
SE-CS30-26.............................Ground-Fault
CT, 30-A-primary rating,
26-mm (1.0”) window
SE-CS30-70............................ Ground-Fault CT,
30-A-primary rating,
70-mm (2.7”) window
Accessories:
RK-332 ................................... Remote Indication and
Reset,
Includes two 120-V pilot
lights, a reset push button,
and legend plates
SE-IP65CVR-G...................... Hinged transparent cover,
IP65
SE-MRE-600 .......................... Moisture-resistant
enclosure for ER-1000HV
Software: (1)
SE-FLASH ............................. Firmware Upgrade
Program
SE-MON330 .......................... SE-330 Data-Display
Program for PC
NGR Monitor
Set-Point Assistant ................. Setting Guide
NOTES:
(1)
Available at www.littelfuse.com/relayscontrols.
Page 27
Rev. 4-A-112913
8. WARRANTY
The SE-330HV Neutral-Grounding-Resistor Monitor is
warranted to be free from defects in material and
workmanship for a period of five years from the date of
purchase.
Littelfuse Startco will (at Littelfuse Startco’s option)
repair, replace, or refund the original purchase price of an
SE-330HV that is determined by Littelfuse Startco to be
defective if it is returned to the factory, freight prepaid,
within the warranty period. This warranty does not apply
to repairs required as a result of misuse, negligence, an
accident, improper installation, tampering, or insufficient
care. Littelfuse Startco does not warrant products
repaired or modified by non-Littelfuse Startco personnel.
SE-330HV Neutral-Grounding-Resistor Monitor
9. TEST PROCEDURES
9.1 RESISTOR-FAULT TESTS
Perform tests with system de-energized and supply
voltage applied to the SE-330HV.
9.1.1 CALIBRATION AND OPEN TEST
Test Equipment: 100-k and 200-k, 1/4-watt, 1%
calibration resistors (calibration resistors
supplied with SE-330HV).
Procedure:
 Remove connections to terminals 6 and 7.
 Connect the 100-k resistor to terminals 6 and 7.
 Set switch S5 to the 100-k position.
 Perform calibration as per Section 2.2.
 The CALIBRATED LED should be on. Press RESET.
 Remove the 100-k resistor and wait for 12 seconds.
PASS: The SE-330HV should trip on resistor fault.
 Connect the 200-k resistor to terminals 6 and 7.
 Set switch S5 to the 200-k position.
 Perform calibration as per Section 2.2.
The CALIBRATED LED should be on.
 Press RESET.
 Remove the 200-k resistor and wait for 12 seconds.
PASS: The SE-330HV should trip on resistor fault.
NOTE: Resistor-fault-trip reset can take up to one second.
9.1.2 VOLTAGE TEST
Test Equipment: 0 to 250 Vac voltage source and multimeter.
NOTE: Use an isolation transformer if the test-voltage source
does not provide dc continuity for the SE-330HV resistancemeasuring circuit.
NOTE: Applying the test voltage to the R and G terminals will
damage the SE-330HV and the ER sensing resistor. The VN
TRIP LEVEL is the trip voltage at terminal N, not terminal R.
Procedure:
 Check the ER sensing resistor connection to the
SE-330HV.
 Disconnect the wire from sensing-resistor terminal N. A
resistor-fault will occur.
 Set the voltage source to 0 V.
 Connect the voltage source between sensing resistor N and
G terminals.
 Set the VN TRIP LEVEL (VAC) to 100.
 Press RESET.
 The RESISTOR FAULT TRIP LED should be off.
 Increase the test voltage to 120 Vac for 100-k sensors or
240 Vac for 200-k sensors and wait 12 seconds
PASS: The SE-330HV should trip on RESISTOR
FAULT. A time-delayed ground-fault trip follows the
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resistor-fault trip if neutral voltage persists after the resistor
fault.
9.2 SENSING-RESISTOR TEST
Test Equipment: Multimeter.
Procedure:
 Disconnect the sensing resistor.
 Measure the resistance between sensing-resistor terminals
R and N.
PASS: Resistance should be between 98 and 102 k for
100-k sensing resistors. Resistance should be between
196 and 204 k for 200-k sensing resistors.
 Measure the resistance between sensing-resistor terminals
R and G in both directions.
PASS: Resistance should be greater than 10 M in
both directions.
9.3 ANALOG-OUTPUT TEST
Test Equipment: Multimeter with a mAdc scale.
Procedure:
 Connect the 4–20-mA output as a self-powered output as
shown in Fig. 3. Measure the current from terminal 20 to
terminal 21.
PASS: With no CT current, the analog output should be
4 mA.
 Output is linear to 20 mA. Output is 20 mA when CTprimary current is equal to the CT-primary rating.
9.4 GROUND-FAULT PERFORMANCE TEST
To meet the requirements of the National Electrical
Code (NEC), as applicable, the overall ground-fault
protection system requires a performance test when first
installed. A written record of the performance test is to be
retained by those in charge of the electrical installation in
order to make it available to the authority having
jurisdiction. A test-record form is provided for recording
the date and the final results of the performance tests.
The following ground-fault system tests are to be
conducted by qualified personnel:
a) Evaluate the interconnected system in accordance with
the overall equipment manufacturer’s detailed
instructions.
b) Verify proper location of the ground-fault current
transformer. Ensure the cables pass through the
ground-fault-current-transformer window. This check
can be done visually with knowledge of the circuit.
The connection of the current-transformer secondary
to the SE-330HV is not polarity sensitive.
c) Verify that the system is correctly grounded and that
alternate ground paths do not exist that bypass the
current transformer.
High-voltage testers and
resistance bridges can be used to determine the
existence of alternate ground paths.
SE-330HV Neutral-Grounding-Resistor Monitor
d) Verify proper reaction of the circuit-interrupting
device in response to a simulated or controlled groundfault current. To simulate ground-fault current, use
CT-primary current injection. Fig. 20 shows a test
circuit using an SE-400 Ground-Fault-Relay Test Unit.
The SE-400 has a programmable output of 0.5 to 9.9
A for a duration of 0.1 to 9.9 seconds. Set the test
current to 120% of GF TRIP LEVEL. Inject the test
current through the current-transformer window for at
least 2.5 seconds. Verify that the circuit under test has
reacted properly. Correct any problems and re-test
until the proper reaction is verified.
DATE
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TABLE 4. GROUND-FAULT-TEST RECORD
TEST RESULTS
e) Record the date and the results of the test on the
attached test-record form.
NOTE: Do not inject test current directly into CT-input
terminals 8, 9, 10, and 11.
NOTE: For accurate trip-time measurement, the fault
current should not be re-applied for the time defined by the
GF TRIP TIME setting to allow the trip accumulator to
initialize.
NEUTRAL
NOTE 1
TO SE-330HV
TO SENSING
RESISTOR
TERMINAL N
NGR
L
N
11
3
5
OP1
8
9
12
L1
L2
1
REMOTE
INPUT
OP2
SE-400
RMT1
RMT2
NOTE:
1. USE MULTIPLE WRAPS FOR TEST CURRENTS > 9.9 A.
FIGURE 20. Ground-Fault-Test Circuit.
Retain this record for the authority having jurisdiction.
SE-330HV Neutral-Grounding-Resistor Monitor
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