1340 TROUBLESHOOTING GUIDE

1340 TROUBLESHOOTING GUIDE
SYMTOM
STEP
DIAGNOSTIC PROCEDURE
A. Unit does
not turn on
when the ON
pushbutton is
depressed
1
Measure line-to-line input voltage at the
disconnect switch with an AC voltmeter
on the 500V AC scale.
CONT.
2
DISC.
SWITCH
OFF
Turn off input power at the disconnect
switch. Check the continuity of
installed controls and contacts per
connection diagrams.
3
DISC
SWITCH
OFF
Check for open, (N.C.), Thermal
Overloads OTS-1 & OTS-2. If the drive
has a Motor Overload Relay, (Option
T), it's N.C. contact should be closed.
4
DISC.
SWITCH
OFF
Check for open fuses F3, F4, & F5.
PROBABLE
FAILURE OR
INDICATION
Input line-to-line voltage
below 207V AC or above
253V AC.
Missing wires, poor
connections, or improper
controls, (e.g.
momentary contacts used
where maintained
contacts are required).
Open OTS-l contacts
indicate 1st Bus not fully
charging - Possible
transistor damage to
Chopper or Brake
Modules. Go to steps B2
& B3.
Open OTS-2 may
indicate a brake problem.
Heavy Duty Braking may
be required. Contact
your AllenBradley CSS
Area Service Center.
One or more fuses
blown.
REPAIR PROCEDURE
Correct external line voltage
to 230V AC, ±10%.
NOTE: If necessary, refer to
factory for information about
30 Input Isolation
Transformers.
Verify that connections and
controls are as shown in the
connection diagrams.
It may be necessary to wait
approximately (5) minutes for
thermal protection devices to
cool down.
NOTE: If manual reset type,
verify that the manual reset
lever has been depressed.
Replace blown fuses. Go to
step A5.
5
DISC .
SWITCH
OFF
For 10 & 15 HP drives, if F3, F4, or F5
are blown, check Rectifier Assemblies
CR1 and CR4 as follows:
< 50 Ohms indicates a
leaky or shorted rectifier
diode.
Replace Rectifier Assembly
CR1 and/or CR4. Go to step
A6.
< 50 Ohms indicates a
leaky or shorted rectifier
diode.
Replace Rectifier Assembly
CR4. Go to step A6.
F6 blown.
NOTE: If any faulty
diodes were found on
Rectifier Assembly CRl.
F6 will be likely to fail.
a) K2 relay not
energized.
Replace F6.
VOM (Rx1 SCALE)
(+)
(-)
Reading
CR1 (+)
CR1 (+)
CR1 (+)
CR4 (A)
CR4 (B)
CR4 (C)
CR1 (A)
CR1 (B)
CR1 (C)
CR4 (-)
CR4 (-)
CR4 (-)
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
For 20-40 HP drives, if F3, F4, or F5
are blown, check Rectifier Assembly
CR1 as follows:
VOM (Rx1 SCALE)
(+)
(-)
6
DISC
SWITCH
OFF
7
CONT.
8
DISC
SWITCH
OFF
CR1 (+) CR1 (A)
CR1 (+) CR1 (B)
CR1 (+) CR1 (C)
CR1 (A) CR1 (-)
CR1 (B) CR1 (-)
CR1 (C) CR1 (-)
Check Fuse F6
Reading
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
With the enclosure door open and the
hinged panel door closed, turn on
power at the disconnect switch. Press
the ON pushbutton and observe the
relay state of Contactor K2
Turn off power at the disconnect
switch. Check fuses Fl & F7.
b) K2 relay energized.
c) K2 relay energizes
only momentarily when
ON pushbutton is
depressed
a) Fl blown.
b) F7 blown.
a) Go to step A8.
b) Go to step B1 to check Bus
voltage.
c) Go back to step A2 and
carefully recheck ON/OFF
pushbutton controls.
a) Replace F1 and go to step
A9.
b) Replace F7 and go to step
A10.
SYMPTOM
STEP
DIAGNOSTIC PROCEDURE
A. Unit does not turn
on when the ON
pushbutton is
depressed.
9
Turn on power at the disconnect switch DO NOT press the ON pushbutton - and
measure the primary and secondary
voltages of Transformer T1 as follows:
Voltmeter on 250V AC SCALE
Terminal No.'s
Reading
1 &2
230V AC,
± 10%
3&4
120V AC
± 15%
REPAIR
PROCEDURE
Replace Transformer
T1.
5&6
10
B. Main Contactor K1
does not energize.
CONT.
1
42 V AC
± 15%
With the AC voltmeter still on the 250V
AC scale, press the ON pushbutton and
measure the voltage across terminals 9
& 10 on Contactor K2.
Turn off power at the disconnect switch.
Set the manual speed
pot fully CCW to minimum speed. With
a voltmeter set on the 500V DC scale,
connect the (+) lead to the (+) side of
the 1st Bus Bar and the ( - ) lead to the
common ( -) Bus Bar. Turn on power at
the disconnect switch and press the ON
pushbutton. Wait approximately (3)
seconds for the 1st Bus to "precharge"
before taking a reading.
PROBABLE
FAILURE
OR INDICATION
Secondary voltages not
present or not within
limits.
NOTE: If primary
reads 230V AC, +10%,
and F1 fails repeatedly
Transformer T1 must
be removed and
"bench" tested.
Voltage reads 120V AC
+15% but K2 does not
energize.
Replace Contactor
K2.
a) DC voltage <5V DC.
a) Go to step B2.
b) DC voltage
approximately 40V DC.
b) Go to step B3.
c) DC voltage is ≥275V
DC.
NOTE: When DC
voltage is ≥275V DC,
LED CR15 on Power
Supply board PS-1 will
be lit.
c) If LED CR15 on
Power Supply board
PS-1 IS NOT lit,
replace PS-1. If LED
CR15 IS lit, go to step
B4
2
DISC.
SWITCH
OFF
CONT.
Turn off power at the disconnect switch.
Remove the black plastic covers from
Chopper SW Modules SM-1 & 2 - (10 &
15 HP), or SM-1, 2, & 3 - (20-40 HP).
Remove the large, BLACK, 10 AWG
wires from their terminal posts. With a
VOM set on the Rx1 SCALE, connect
the ( + ) VOM lead to the disconnected
BLACK wire. Connect the (-) VOM lead
to the large, WHITE, 10 AWG wire at
it's terminal post. Check each chopper
module individually. Repeat the
procedure with the VOM set on the
Rx10K scale.
a) On the Rx1 scale the
Ohms reading should be
infinity. A low reading,
(<10 Ohms), indicates a
shorted transistor.
a) Replace faulty
module(s) and
reconnect the black
wires to their terminal
posts. Go to step B5.
b) On the Rx10K scale
the Ohms reading
should be ≥500K
Ohms. A reading below
500K Ohms indicates a
leaky transistor.
b) Replace faulty
module(s) and
reconnect the black
wires to their terminal
posts. Go to step B5.
NOTE: All transistors
on the Chopper SW
Modules are
individually fused. A
blown fuse will
indicate a failed
transistor.
HOWEVER, for
purposes of verifying
drive performance and
for troubleshooting
under LIGHT LOAD,
(≤50% of drive's rated
KVA), or NO LOAD
conditions, fuses may
be removed from
faulty transistors.
IN NO CASE should
a module be installed
with less than (6)
functional transistors.
SYMPTOM
STEP
DIAGNOSTIC PROCEDURE
B. Main
Contactor
K1 does not
energize.
3
DISC.
SWITCH
OFF
At Brake SW Module SM-5 (10 &
15 HP), or SM-7 (20-40 HP),
remove the large, BLACK, 10
AWG wire from it's terminal post.
With the VOM set on the Rx1
scale, connect the ( + ) VOM lead
to the disconnected BLACK wire.
Connect the (-) VOM lead to the
large, WHITE, 10 AWG wire at it's
terminal post. Repeat the
procedure with the VOM set on
the Rx10K scale.
4
5
CONT.
PROBABLE
FAILURE OR
INDICATION
a) On the Rx1
scale the Ohms
reading should
be infinity. A
low reading,
(<10 Ohms),
indicates a
shorted
transistor.
b) On the Rx10K
scale the Ohms
reading should
be ≥500K Ohms.
A reading below
500K Ohms
indicates a leaky
transistor.
With the disconnect switch OFF,
connect a voltmeter to Contactor
K1, terminals 1 & 4, (coil
terminals). With the voltmeter set
on the 250V AC scale, turn on
power at the disconnect switch and
press the ON pushbutton. After
approximately (6) seconds the
voltage should be 120V AC,
±15%.
a) Voltage not
present or
insufficient.
Turn off power at the disconnect
switch. Set the manual speed pot
fully CCW - minimum speed. With
the voltmeter set on the 500V DC
scale, connect the (+) lead to the
(+) side of the 1st Bus Bar and the
( - ) lead to the common ( - ) Bus
Bar. Turn on power at the
disconnect switch and press the
ON pushbutton. Wait
approximately (3) seconds for the
1st Bus to precharge before taking
a reading
a) 1st Bus does
not charge to
275V DC after
Chopper and
Brake SW
Modules verified
''normal" in steps
B2 & B3.
b) Proper
voltage present,
BUT Contactor
K1 is not
energized.
b) 1st Bus
charges to 275V
DC and K1
energizes.
REPAIR PROCEDURE
a) Replace the Brake SW Module and reconnect
the black wire to it's terminal post. Go to step
B5.
b) Replace the Brake SW Module and
reconnect the black wire to it's terminal post.
Go to . step B5.
NOTE: All transistors on the Brake SW
Module are individually fused. A blown fuse
will indicate a failed transistor.
HOWEVER, for purposes of verifying drive
performance and for troubleshooting under
LIGHT LOAD (≤50% of drive's rated KVA), or
NO LOAD conditions, fuses may be removed
from faulty transistors.
IN NO CASE should a module be installed
with less than (6) functional transistors.
a) Replace Power Supply board PS-1
b) Replace Contactor K1.
NOTE: Contactor K2 is a pneumatic adjustable
timer and must pull-in prior to Contactor K1
energizing. Delay time for K2 contacts may be
set by the thumbwheel adjust on the timer.
Contacts on K2 SHOULD NOT change from
their normal de-energized state until 2-3
seconds after LED CR15 on Power Supply
Board PS-1 is lit. LED CR15 should light
approximately 3-6 seconds after the ON
pushbutton is pressed.
a) Go to step B6.
NOTE: If 1st Bus does not charge at all - (0V
DC measured) - Go to step B10.
b) Go to step C1.
SYMPTOM
STEP
DIAGNOSTIC PROCEDURE
B. Main
Contactor
K1 does not
energize.
6
DISC.
SWITCH
OFF
Turn off power at the disconnect
switch. Remove the black plastic
guard from the Bus Bank
capacitors. Connect the ( +) VOM
lead to the (+) 1st Bus Bank bar
and the (-) VOM lead to the (-)
1st Bus Bank bar. Push in and
hold the RESET on Contactor K2.
The VOM should read between 5
and 25 Ohms and slowly rise to
above 30 Ohms.
7
DISC.
SWITCH
OFF
8
DISC.
SWITCH
OFF
9
DISC.
SWITCH
OFF
Leave the (-) VOM lead
connected to the (-) 1st Bus Bank
bar and the VOM on Rx1.
Disconnect all wires to the ( + )
1st Bus Bank bar. Verify that the
disconnected wires are not
touching. Connect the (+) VOM
lead to the (+) 1st Bus Bank bar
Leave the ( - ) VOM lead
connected to the (-) 1st Bus Bank
bar and the VOM on Rx1.
Connect the ( + ) VOM lead to
C8(+) - (10 & 15 HP), or C15(+) (20-40 HP), and check indication.
Repeat for C9 (10 & 15 HP), or
C16 (20-40 HP)
With the VOM on the Rx1 scale,
check Rectifier Assembly CR2 as
follows:
VOM
(+)
CONT.
CR2 (+)
CR2 (+)
(AC)
(AC)
(-)
(AC)
(AC)
CR2(-)
CR2(-)
PROBABLE FAILURE
OR INDICATION
A sustained low reading,
(<25 Ohms), indicates a
short on
the 1st Bus.
REPAIR PROCEDURE
Go to step B7.
- EITHER•· Shorted Bus Bank
capacitor C1, C2, or C3 (10 & 15 HP), or C1-C6 (20-40 HP).
•· Shorted Rectifier
Assembly CR2.
•· Shorted Steering Diode
Assembly DD-1 or DD-2.
•· Pinched wires to the
Bus Bank capacitors.
a) A low reading, (≤100
Ohms), indicates a
shorted or leaky Bus
capacitor.
b) A high reading, ( >100
Ohms), indicates the fault
is elsewhere.
a) A low reading, (≤100
Ohms), indicates a
shorted or leaky Bus
capacitor.
b) A high reading, (>100
Ohms), indicates the fault
is elsewhere.
a) A low ohmmeter
reading, (< 50 Ohms),
indicates a shorted or
leaky Rectifier Assembly
CR2.
a) Remove the brass bar(s)
from the (+) 1st Bus Bank.
Isolate and replace faulty
Bus capacitor(s). Replace
brass bar(s)
b) Go to step B8.
NOTE: When checking
capacitors, always wait for
the ohmmeter reading to
stabilize.
a) Replace faulty
capacitor(s)
b) Go to step B9
a) Replace CR2.
Reading
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
b) A high reading
indicates the fault is
elsewhere.
b) Carefully reconnect all
wires to the (+) 1st Bus
Bank bar. Replace the
black plastic Bus Bank
guard. Go to step B10.
SYMPTOM
B. Main
Contactor K1
does not
energize.
STEP
DIAGNOSTIC PROCEDURE
10
DISC.
SWITCH
OFF
With the VOM on the Rx1 scale, check
precharge current limiting resistors R1 and R4
on Resistor Assembly 41103 - (10 & 15 HP),
or R1 and R2 on Resistor Assembly 41101 (20-40 HP).
11
Set the VOM on the 500V DC scale. Set the
manual speed pot fully CCW - minimum speed.
Connect the ( + ) VOM lead to the (+) side of
the 1st Bus Bar and the (-) VOM lead to the
common (-) Bus Bar. Apply power at the
disconnect switch and press the ON
pushbutton. After approximately (3) seconds
bus voltage should be 275V DC and LED
CR15 on Power Supply board PS-1 should be
lit. After approximately (6) seconds, Contactor
K1 should energize.
12
DISC.
SWITCH
OFF
a) Turn off power at the disconnect switch and
check fuse F2.
b) Set the VOM on the Rx1 scale and check
Rectifier Assembiy CR3 as follows:
PROBABLE FAILURE
OR INDICATION
Each resistor should read
10 Ohms. An open
resistor will disable
precharge.
a) Bus not charging or
voltage to low.
REPAIR
PROCEDURE
Replace Resistor
Assembly 41103 or
41101.
NOTE: An open
resistor will cause
overheating. Check
wire insulation near
the Resistor Assembly
for damage. Replace
Thermal Overload
OTS-1 and wires if
damaqe has occurred.
a) Contact your
Allen-Bradley Area
Service Center.
b) Voltage is ≥275V DC,
LED CR15 is lit, but K1
is not energized.
b) Replace Control
Logic board CL1 .
c) K1 is energized, and
LED 1 on Brake Board
BB-1 is lit or flickering
c) Turn potentiometer
R2 on BB-1 CCW
until LED 1 turns off,
then turn an additional
1/2 turn CCW.
NOTE: If LED 1
does not turn off,
replace Brake Board
BB-1.
d) Bus voltage is ≥275V
DC, but CR15 is not lit.
a) F2 blown.
d) Go to step B12a)
a) Replace F2 and go
to step b).
bl) <50 Ohms indicates a
shorted or leaky diode on
CR3.
b1 ) Replace CR3.
b2) VOM reads > 50
Ohms.
b2) Go to step B13.
VOM
(+)
CONT.
(-)
CR3 (+) (AC)
CR3 (+) (AC')
(AC)
CR3 (-)
(AC')
CR3 (-)
Readings
>50 Ohms
>50 Ohms
>50 Ohms
>50 Ohms
13
DISC.
SWITCH
OFF
a) Disconnect twist-lock connector J4 at
Converter Board CO-1. With the VOM on the
Rx1 scale, connect the (+) VOM lead to C7(+)
(10 & 15 HP), or C14(+) (20-40 HP). Connect
the (-) VOM lead to the ( - ) terminal of the
capacitor. The VOM should read low and rise
to a high reading, (>100 Ohms).
al) >100 Ohms indicates
the fault is elsewhere.
a1) Go to step b).
a2) A low ohmmeter
reading, (≤100 Ohms,
indicates a shorted or
leaky converter capacitor.
a2) Replace faulty
capacitor
b) With the VOM on the Rx10 scale, check
CR3 and CR4 on Converter Board CO-1 as
follows:
bl) ≥lM Ohm indicates no
fault.
bl) Go to step B14.
b2) < 1M Ohm indicates
faulty diodes or
transistors on Converter
Board CO-1
b2) Replaces CO-1.
a) Voltage not present or
insufficient.
a) Replace Power
Supply board PS-1
and recheck CO-1. If
voltage is still not
present or insufficient
contact your
Allen-Bradley Area
Service Center
VOM
14
(+)
(-)
CR4
(Cathode)
CR4
(Anode)
Readings
≥1M
Ohm
CR3
CR3
≥1M
(Cathode) (Anode)
Ohm
Reconnect twist-lock connector J4 to Converter
Board CO-1. Insure that
ALL connections previously removed have
been replaced. Set the VOM on the 50V DC
scale. Reapply power at the disconnect switch
and press the ON pushbutton. Check Power
Supply board PS-1 as follows:
(+)
VOM
(-)
C4 (+)
C6 (-)
C6 (-)
C5 (-)
C6 (+)
C6 (-)
Reading
+5.3V DC
+ 10%
+15V DC
+ 10%
+15V DC
+ 10%
b) Voltage present and
sufficient.
b) Go to step C1.
SYMPTOM
STEP
DIAGNOSTIC PROCEDURE
C. Motor
starts
but trips
off drive.
1
Turn off power at the disconnect
switch and disconnect the motor from
the drive at TB1, terminals 1, 2, & 3.
Set the manual speed pot fully CCW minimum speed. Turn on power at the
disconnect switch and press the ON
pushbutton. If the drive has
RUN/STOP pushbuttons, press RUN.
Slowly turn the speed pot CW.
PROBABLE
FAILURE OR
INDICATION
a) Drive trips off with
motor disconnected Possible faulty Chopper
SW Module(s).
b) Drive trips off with
motor disconnected Chopper SW Module(s)
are correct per step B2.
REPAIR PROCEDURE
a) Go to step B2.
b) Go to step B3 to check Brake
SW Module.
c) Go to step C7.
2
DISC.
SWITCH
OFF
CONT.
Turn off power at the disconnect
switch. Remove the black plastic
covers from Pull Down SW Modules
SM-3 & 4 - (10 & 15HP), or SM-4, 5.
& 6 - (20 & 40HP). Remove the large,
BLACK, 10 AWG wires from their
terminal posts. With a VOM set on the
Rx1 scale, connect the (+) VOM lead
to the disconnect BLACK wire.
Connect the (-) VOM lead to the large ,
WHITE, 10 AWG wire at it's terminal
post. Check individually. Repeat the
procedure with the VOM set on the
Rx10K scale.
c) Drive does not trip
off with motor
disconnected.
a) On Rx1 scale the
Ohms reading should be
infinity. A low reading,
(<10 Ohms), indicates a
shorted transistor.
b) On Rx10K scale the
Ohms reading should be
≥500K Ohms. A
reading below 500K
Ohms indicates a leaky
transistor.
a) Replace faulty module(s) and
reconnect the black wires to their
terminal posts. Go to step C5.
b) Replace faulty module(s) and
reconnect the black wires to their
terminal posts. Go to step C5.
NOTE: All transistors on the Pull
Down SW Modules are individually
fused. A blown fuse will indicate a
failed transistor. HOWEVER, for
purposes of verifying drive
performance and for
troubleshooting under LIGHT
LOAD (≤50% of drive's rated
KVA), or NO LOAD conditions,
fuses may be removed from faulty
transistors. IN NO CASE should a
module be installed with less than
(6) functional transistors.
SYMPTOM
STEP
DIAGNOSTIC PROCEDURE
C. Motor starts
but trips
off drive.
3
a) With the motor still disconnected, turn on
power at the disconnect switch. Set the
manual speed pot fully CCW- minimum
speed. If the drive has RUN/STOP
pushbuttons, DO NOT press RUN. Place the
toggle switch located on the bottom of
Chopper Driver Board DB-1 in the OFF
position. Press the ON pushbutton. LED
CR7, (Pull Down LED), on Chopper Driver
Board DB-1 should light. After
approximately (3) seconds, LED CR15, (Bus
Sense LED), on Power Supply Board PS-1
should light. After approximately (6)
seconds, one LED on each of the Power
Driver Boards, DB-2, 3, & 4 should light.
NOTE: The above sequence will occur
ONLY if the drive is equipped with
RUN/STOP AND/OR the drive has a
minimum speed pot setting of (0) Hz.
b) If the drive has RUN/STOP pushbuttons,
press RUN, slowly turn the speed pot CW.
Observe LEDs CR7 & CR4 on Chopper
Driver Board DB-1. CR7 should dim while
CR4 should remain off. LEDs on Power
Driver Boards DB-2, 3, & 4 will alternately
start to flash. As the speed is increased
above 10 Hz, all LEDs on the Power Driver
Boards will appear to be lit constantly.
4
DISC.
SWITCH
OFF
CONT.
Incorrect LED indication on a Power Driver
Board indicates a faulty (+) or (-) SW
Module connected to that Power Driver
Board. Turn off input power at the
disconnect switch and remove the black
plastic covers from the (+) and (-) SW
Modules associated with the faulty Power
Driver Board. Remove both the large, (10
AWG) and small, (18 AWG) . BLACK wires
from their terminal posts. With the VOM set
on the Rx10K scale, connect the (+) VOM
lead to the large disconnected BLACK wire.
Connect the (-) VOM lead to the large,
WHITE, 10 AWG wire at it's terminal post.
The VOM should read low and slowly rise
to approximately 500K Ohms after 10-15
seconds Repeat for each SW Module
PROBABLE
FAILURE OR
INDICATION
a) None or both LEDs
on Power Driver
Boards DB-2, 3, or 4
are lit.
b1) LEDs on Power
Driver Boards DB-2,
3, or 4 not indicating
as explained.
b2) LEDs on Chopper
Driver Board DB-1
not indicating as
explained.
b3) All LEDs
indicating normally.
A sustained low
reading indicates a
shorted or leaky SW
Module.
REPAIR
PROCEDURE
a) Replace faulty
Power Driver
Board(s).
NOTE: DB-2, 3, & 4
may be interchanged
to determine if the
problem stays with the
board or whether
wiring to the board is
at fault.
b1) Go to step C4.
b2) Go to step C5.
b3) Go to step C7.
Replace faulty SW
Module(s). Reconnect
all SW Module wires.
Go to step C7.
SYMPTO
M
C. Motor
starts but
trips off
drive.
STEP
DIAGNOSTIC PROCEDURE
5
With the motor still disconnected and the
disconnect switch off, set the manual speed
pot fully CCW minimum speed. Switch the
toggle switch on Chopper Driver Board
DB-1 to ON. With the VOM set on the
500V DC scale, connect the ( + ) VOM
lead to the ( +) side of the 2nd Bus Bar and
the (-) VOM lead to the common ( -) Bus
Bar. Turn on power at the disconnect
switch and press the ON pushbutton. Wait
approximately (6) seconds for Contactor
K1 for energize. If the drive has
RUN/STOP pushbuttons. press RUN and
slowly turn the speed pot CW. Observe the
vo!tage and note the action of LEDs CR4,
(Chopper LED), and CR7, (Pull Down
LED), on Chopper Driver Board DB-1. The
voltage should slowly increase from O to
280V DC while CR7 dims and CR4 lights.
6
DISC.
SWITCH
OFF
CONT.
a) Turn off power at the disconnect switch.
Remove the black plastic guard from the
Bus Bank capacitors. Connect the (+) VOM
lead to the (+) 2nd Bus Bank bar. Connect
the (-) VOM lead to the (-) 2nd Bus Bank
bar. The VOM should read low and slowly
rise to above 25 Ohms.
PROBABLE FAILURE OR
INDICATION
a) Voltage and LEDs
indicating correctly.
b) Voltage not present. CR7
remains lit and CR4 remains
off as speed pot is turned
CW.
NOTE: Insure that the drive
is processing the speed signal
by checking the LEDs on
Power Driver Boards DB-2,
3, and 4. LEDs should
alternately start to flash as
the speed pot is turned CW.
Above 10 Hz, they will
appear to be lit constantly.
c) Voltage not present. CR7
goes off but CR4 remains off
when speed pot is turned
CW.
d) Voltage not present or
very low, (<10V DC). CR7
begins to dim, CR4 begins to
light then drive trips off.
a) A sustained low reading
indicates a short on the 2nd
Bus.
b) Leave the (-) VOM lead connected to the
(-) 2nd Bus Bank bar and the VOM on Rx1.
Disconnect all wires to the (+) 2nd Bus
Bank bar. Insure that the disconnected
wires are not touching. Connect the (+)
VOM lead to the (+) 2nd Bus Bank bar.
b1) A high reading, (>100
Ohms), indicates the fault is
elsewhere.
b2) A low reading, (≤100
Ohms), indicates a shorted or
leaky Bus capacitor.
c) Leave the (-) VOM lead connected to the
(-) 2nd Bus Bank bar and the VOM on Rx1.
Connect the (+) VOM lead to C10 (+) (10
& 15 HP), or C17 (+) (20-40 HP), on the
drive back panel.
c1) A high reading, (>100
Ohms), indicates the fault is
elsewhere.
c2) A low reading indicates a
shorted capacitor.
REPAIR
PROCEDURE
a) Go to step C7.
b) Replace Control
Logic board CL-1. Go
to step C7.
c) Replace Chopper
Driver Board DB-1. Go
to step C7.
d) Go to step C6.
a) Go to step b).
b1) Go to step c).
b2) Remove the brass
bar from the (+) 2nd
Bus bank. Isolate and
replace faulty Bus
capacitor(s). Replace
brass bar. Go to step
C7.
c1) Carefully reconnect
all wires to the ( +) 2nd
Bus Bank bar AND
ALL OTHER WIRES
previously removed. Go
back to step C3.
c2) Replace faulty
capacitor. Go to step
C7.
SYMPTOM
STEP
C. Motor
starts but
trips off
drive.
7
DISC.
SWITCH
OFF
8
9
CONT.
DIAGNOSTIC PROCEDURE
Check Fuse F6.
Carefully reconnect all wires to the (+)
2nd Bus bar AND ALL OTHER
WIRES previously removed. With the
motor still disconnected and the
disconnect switch off, set the manual
speed pot fully CW maximum speed.
With the VOM set on the 500V AC
scale, connect the ( + ) VOM lead to
TB1, terminal 1, and the (-) VOM lead
to TB1, terminal 2. Turn on power at the
disconnect switch and press the ON
pushbutton. If the drive has RUN/STOP
pushbuttons, press RUN. Wait
approximately (6) seconds and measure
the voltage.
a) Test the motor and leads for
"grounds" or "opens" and repair as
required. Turn off power at the
disconnect switch and reconnect the
motor at TB1, terminals 1, 2, & 3. If the
drive has manual reset motor overload
relays, insure that they have been
RESET. Set the manual speed fully
CCW - minimum speed. Turn on power
at the disconnect switch and press the
ON pushbutton. If the drive has
RUN/STOP pushbuttons, press RUN.
Wait approximately (6) seconds, then
SLOWLY turn the speed pot fully CW to
maximum speed. SLOWLY turn the
speed pot back to minimum speed.
PROBABLE
FAILURE OR
INDICATION
F6 blown
a) Voltage between
200 to 250V AC Repeat procedure with
(+) VOM lead
connected to TB1,
terminal 3.
REPAIR PROCEDURE
Replace F6. Go to step C8.
a) Voltage still between 200 to
250V AC - Go to step C9.
b) Contact your Allen-Bradley
Area Service Center.
b) Voltage not present.
a1) Motor follows
speed pot signal and
runs smoothly.
a1) Go to step b).
a2) Motor starts but
runs unstable or stalls
at certain speeds.
a2) It may be necessary to
change capacitor C29 on
Control Logic board CL-1.
Contact your Allen-Bradley
Area Service Center.
a3) Drive trips as soon
as speed pot is turned
CW.
a3) Improper motor rating for
the drive. Contact your
Allen-Bradley Area Service
Center.
SYMPTOM
STEP
C. Motor starts
but trips off
drive.
9
DIAGNOSTIC
PROCEDURE
b) With the motor still
connected, press the OFF
pushbutton and set the
speed pot fully CCW minimum speed. Press the
ON pushbutton. If the drive
has RUN/STOP
pushbuttons, press RUN.
Wait approximately (6)
seconds, then QUICKLY
turn the speed pot CW to
maximum speed. Once the
motor has reached full
speed, QUICKLY turn the
speed pot back to minimum
speed.
PROBABLE FAILURE
OR INDICATION
bl ) Motor follows speed
pot signal and runs
smoothly.
b2) Drive trips upon
acceleration as speed pot
is quickly turned CW.
REPAIR PROCEDURE
b1) Contact your Allen-Bradley
Service Center.
b2) Acceleration Rate set too High,
(potentiometer R86 on Control
Logic Board CL-1).
CAUTION: Do not adjust RED
sealed potentiometers. Breaking of
these seals will void any drive
warranties. Incorrect adjustment
may cause damage to the motor
and/or drive.
b3) Drive trips upon
deceleration as speed pot
is quickly turned CCW.
b3) Deceleration Rate set to High.
(potentiometer R87 on Control
Logic Board CL-1)
CAUTION: Do not adjust RED
sealed potentiometers. Breaking of
these seals will void any drive
warranties. Incorrect adjustment
may cause damage to the motor
and/or drive.
NOTE: If LED 1 on Brake Board
BB-1 remains on or flickers when
the speed pot is fully CCW minimum speed, BB-1 may need
readjustment. Go back to step
B11c).
b4) Drive trips upon
deceleration - Braking
Resistor Heater(s) R3 (10 & 15 HP), or R5 &
R6 - (20-40 HP)
overheated and/or Over
temperature switch
OTS-2 tripped.
b4) Heavy Duty Dynamic Braking,
(Option K2), may be required.
Contact your Allen-Bradley Area
Service Center.