Fuse Diagnostic Sizing Charts

Fuse Diagnostic Sizing Charts
Ballasts
Indoor
Fluorescent
Consult fixture manufacturer for size and type.
All Other (Mercury,
Sodium, etc.)
Consult fixture manufacturer for size and type.
Fuse & Holder Recommendations
Fuse
GLR
GMF
GRF
Holder(s)
HLR
Fuse
GLQ
GMQ
Holder(s)
HLQ
Fuse & Holder Recommendations
Fuse
BAF
BAN
KTK
FNM
FNQ
FNW
Holder(s)
HPF
HPS
Fuse
KTK-R
FNQ-R
LP-CC
Holder(s)
HPS-RR
HPF-RR
KTQ
BBS
HPS-L
HPF-L
Fuse
SC 0-15
SC 20
SC 25-30
Holder(s)
HPF-EE
HPS-EE
HPF-JJ
HPS-JJ
HPF-FF
HPS-FF
Fuse & Holder Recommendations
Outdoor
Mercury, Sodium, etc.
Consult fixture manufacturer for size and type.
Fuse
BAF
BAN
KTK
FNM
FNQ
FNW
Holder(s)
HEB
HEX
HPC-D
Fuse
KTK-R
FNQ-R
LP-CC
Holder(s)
HEY
Capacitors (NEC® 460)
Protected by
Time-Delay Fuses.
150% to 175% of Full Load Current
Protected by
Non-Time-Delay Fuses.
250% to 300% of Full Load Current.
On Load Side of Motor Running
Overcurrent Device.
202
Fuse Recommendations
Volts
0-250
0-600
0-600
Protection recommended as shown, but not required.
Fuse(s)
LPN-RK_SP, FRN-R
LPS-RK_SP, FRS-R
LPJ_SP, LP-CC,
FNQ-R, TCF
Fuse Recommendations
Volts
0-250
0-300
0-600
0-600
0-600
Fuse(s)
KTN-R, NON
JJN
KTS-R, NOS
JKS, KTK-R
JJS
©2005 Cooper Bussmann
Fuse Diagnostic Sizing Charts
Electric Heat (NEC® 424)
Size at 125% or next size larger but in no case larger than 60
amps for each subdivided load.
Electric Space Heating
Fuse Recommendation
Volts
0-250
0-300
0-480
0-600
0-600
0-600
Electric Boilers with Resistance
Type Immersion Heating
Elements in an ASME Rated and
Stamped Vessel
Size at 125% or next size larger but in no case larger than 150
amps for each subdivided load.
Fuse(s)
LPN-RK_SP
FRN-R, NON
JJN
SC 25 to SC 60
LPS-RK_SP
FRS-R, NOS
JJS
LPJ_SP, LP-CC
FNQ-R, JKS, KTK-R,
TCF, SC 1⁄2 to SC 20
Mains, Feeders, Branches
Feeder Circuits
(600A & Less)
No Motor Load
100% of non-continuous load plus 125% of continuous load.
Fuse Recommendations
Volts
0-250
0-300
0-600
0-600
0-600
Combination Motor Loads
and Other Loads
Motor Loads
150%* of the FLA of largest motor (if there are two or more motors of
same size, one is considered to be the largest) plus the sum of all
the FLA for all other motors plus 100% of non-continuous, non-motor
load plus 125% of continuous, non-motor load.
150%* of the FLA of largest motor (if there are two or more motors
of same size, one is considered to be the largest) plus the sum of all
the FLA for all other motors.
Fuse(s)
LPN-RK_SP, FRN-R
JJN
LPS-RK_SP, FRS-R
JJS
LPJ_SP, LP-CC
JKS, KTK-R
Fuse Recommendations
Volts
0-25O
0-600
0-600
Fuse(s)
LPN-RK_SP, FRN-R
LPS-RK_SP, FRS-R
LPJ- SP, LP-CC
*A max. of 175% (or the next standard size if 175% does not correspond to a standard size) is allowed for all but wound rotor and all dc
motors.
Main, Branch &
Feeder Circuits
(601-6000A)
©2005 Cooper Bussmann
150% to 225% of full load current of largest motor plus 100% of full
load current of all other motors plus 125% of continuous non-motor
load plus 100% of non-continuous non-motor load.
Fuse Recommendation
Volts
0-600
Fuse(s)
KRP-C_SP
203
Fuse Diagnostic Sizing Charts
Motor Loads (NEC® 430)
Fuse Sized For:
600V & Less
Protected by TimeDelay Fuses
Backup Overload w/ Motor
Starter & Short-Circuit
Protection
Fuse Recommendations
125% of motor FLA or next size larger.
Volts
0-250
0-600
Fuse(s)
FRN-R
FRS-R
Fuse Recommendations
130% of motor FLA or next size larger.
Short-Circuit Only
Protected by Non-Time
Delay Fuses & all
Class CC Fuses
Short-Circuit Only
175%* of motor FLA or next size larger. (If 175% does not correspond to a standard size). If this will not allow motor to start, due to
higher than normal inrush currents or longer than normal
acceleration times (5 sec. or greater), fuse may be sized up to 225%
or next size smaller.
Max. of 300%* of motor FLA or next size larger (if 300% does not
correspond to a standard size). If this will not allow motor to start
due to higher than normal inrush currents or longer than normal
acceleration times (5 sec. or greater), fuses through 600 amps may
be sized up to 400% or next size smaller.
*150% for wound rotor and all DC motors.
Above 600V
Compare the min. melting time-current characteristics of the fuses with the time-current characteristics of the overload relay curve. The
size fuse which is selected should be such that short.circuit protection is provided by the fuse and overload protection is provided by the
controller overload relays.
Volts
0-250
0-600
Fuse(s)
LPN-RK_SP
LPS-RK_SP
Fuse Recommendations
Volts
0-250
0-600
0-600
Fuse(s)
LPN-RK_SP, FRN-R
LPS-RK_SP, FRS-R
LPJ_SP, TCF
Fuse Recommendations
Volts
0-250
0-300
0-600
0-600
0-600
Fuse(s)
KTN-R, NON
JJN
KTS-R, NOS
JJS
LP-CC, JKS, KTK-R
Fuse Recommendations
Volts
2400
4800
7200
Fuse(s)
JCK, JCK-A, JCH
JCL, JCL-A, JCG
JCR, 7.2 WKMSJ
Solenoids (Coils)
Branch Circuit
Fuses
Fuse Recommendation
Size at 125% or next size smaller.
Volts
0-250
0-600
0-600
Supplementary
Fuses
Size at 125% or next size larger.
Fuse Recommendation
Volts
0-32
0-125
0-250
0-500
204
Fuse(s)
Best: LPN-RK_SP
FRN-R
LPS-RK_SP
FRS-R
LPJ_SP, LP-CC
FNQ-R, TCF
Fuse(s)
MDL 9-30A,
FNM 20-30A
MDA 25-30A,
FNM 12-15A
MDL 1⁄16-8A,
MDA 2⁄10-20A,
FNM 1⁄10-10A,
FNW 12-30A,
MDQ 1⁄100-7A
FNQ 1⁄10-30A
©2005 Cooper Bussmann
Fuse Diagnostic Sizing Charts
Transformers 600V Nominal or Less (NEC® 450.3)
Primary
Protection
Only
Primary And
Secondary
Protection
Note: Components on the secondary still need
overcurrent protection
Without Thermal
Overload Protection
With Thermal
Overload Protection
Transformer
Impedance of 6%
or Less
Transformer
Impedance of More
Than 6% But Less
Than 10%
NEC® Maximums
Optimum Protection
Rated primary current less
than 2 amps
125% or next size larger
Max. 300% or next size smaller (See
NEC® 430.72(C) for control circuit transformer maximum of 500%
Rated primary current greater
than or equal to 2 amps but
less than 9 amps
125% or next size larger
Max. 167% or next size smaller
Rated primary current greater
than or equal to 9 amps
125% or next size larger
Max. of 125% or next larger*
Rated secondary current less
than 9 amps
A
A
Rated secondary current 9
amps or greater
B
B
Rated secondary current less
than 9 amps
C
Rated secondary current 9
amps or greater
D
Rated secondary current less
than 9 amps
E
E
Rated secondary current 9
amps or greater
F
F
C
Primary and secondary
fuses at 125% of primary
and secondary FLA or
next size larger
D
% of Primary FLA
(or next FLA size smaller)
A = 250%
B = 250%
C = 600%
D = 600%
E = 400%
F = 400%
% of Secondary FLA
A = 167% or next size smaller
B = 125% or next size larger*
C = 167% or next size smaller
D = 125% or next size larger*
E = 167% or next size smaller
F = 125% or next size larger*
*When 125% of FLA corresponds to a
standard rating, the next larger size is
not permitted.
Fuse Recommendations
Volts
250V
600V
©2005 Cooper Bussmann
Fuse(s)
LPN-RK_SP, FRN-R
KRP-C_SP, LPJ_SP, LPS-RK_SP, FNQ-R, FRS-R, TCF
205
Fuse Diagnostic Sizing Charts
Transformers Over 600V Nominal (NEC® 450.3)
Supervised
Installations
Primary
Protection
Only
Primary at code max. of 250% or next
standard size if 250% does not correspond to a standard rating
Primary and
Secondary
Protection
Transformer
Impedance Less Than
or Equal to 6%
Transformer
Impedance Greater
Than 6% But Less
Than 10%
Primary
at code
max. of
300%
Primary
at code
max. of
300%
Note: Components on the secondary still need
overcurrent protection
Secondary
Over 600V
Secondary at
code max. of
250%
Secondary
600V or
Below
Secondary at
code max. of
250%
Secondary
Over 600V
Secondary at
code max. of
225%
Secondary
600V or
Below
Secondary at
code max. of
250%
Secondary
Over 600V
Secondary at code max. of
250% or next standard size if
250% does not correspond to
a standard rating
Secondary
600V or
Below
Secondary at code max. of
125% or next standard size if
125% does not correspond to
a standard rating
Secondary
Over 600V
Secondary at code max. of
225% or next standard size if
225% does not correspond to
a standard rating
Secondary
600V or
Below
Secondary at code max. of
125% or next standard size if
125% does not correspond to
a standard rating
Fuse Recommendations
Volts
250V
600V
2475V
2750V
2750/5500V
5500V
7200V
Unsupervised
Installations
Transformer
Impedance Less Than
or Equal to 6%
Transformer
Impedance Greater
Than 6% But Less
Than 10%
Primary at code max. of 300%
or next standard size if 300%
does not correspond to a
standard rating
Primary at code max. of 300%
or next standard size if 300%
does not correspond to a
standard rating
8300V
15500V
17500V
24000V
36000V
38000V
Fuse(s)
LPN-RK_SP, FRN-R
LPS-RK_SP, LPJ-_SP,
KRP-C_SP, FRS-R, FNQ-R,
TCF
JCD
JCX
JCW
JCE, JCQ, JCY, JCU,
5.5 ABWNA, 5.5 AMWNA,
5.5 FFN
7.2 ABWNA, 7.2 SDLSJ,
7.2 SFLSJ
JCZ, JDZ, 8.25 FFN
JCN, JDN, JDM, 15.5 CAVH
17.5 CAV, 17.5 SDM
24 SDM, 24 SFM, 24 FFM
36 CAV, 36 SDQ, 36 SFQ
38 CAV
Solid State Devices (Diodes, SCRs, Triacs, Transistors)
Short-Circuit
Protection Only
Fuse Recommendations
“F,” “S,” “K,” & 170M Series fuses sized up to several sizes larger
than full load RMS or dc rating of device.
Volts
0-130
0-250
0-500
0-600
0-700
0-1000
206
Fuse(s)
FWA
FWX
FWH
FWC, KAC, KBC
FWP, 170M Series,
SPP
FWJ, 170M Series,
SPJ
©2005 Cooper Bussmann