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  • Technical | Monster Electrical

Fuse Resistance Values

A cold resistance test of a fuse provides the primary indication of the fuse's integrity. Monster tests and posts resistance values to ensure you and your customer receive a safe-to-install product every time.

Monster Fuses is proud to be the only company to offer an open database of resistance values.

Below are Suggested Amp. ratings for Transformer and Motor Starter applications.

Ratings shown are for general information only.

Proper fuse selection depends on many factors, consult a professional engineer for your application.

Transformer Fuses

Suggested Fuse Current Ratings for Power Transformer Applications
2400V 4160V 7200V 12470V 13800V

KVA
Full
Load
Amps
Fuse
Rating
Amps
Full
Load
Amps
Fuse
Rating
Amps
Full
Load
Amps
Fuse
Rating
Amps
Full
Load
Amps
Fuse
Rating
Amps
Full
Load
Amps
Fuse
Rating
Amps
307.215E4.210E2.45E1.43E1.33E
4510.815E6.210E3.65E2.15E1.93E
751825E10.415E610E3.55E3.15E
112.52740E15.625E915E5.210E4.710E
1503650E20.830E1220E710E6.210E
2255480E31.350E1825E10.415E9.415E
30072100E41.665E2440E13.920E12.520E
500120200E69.4100E4065E23.130E2130E
750180250E104150E60100E34.750E3150E
1000241350E140200E80125E46.365E4265E
1500360600E208300E120200E69.6100E62100E
2000481750E278400E160250E92.5125E84125E
25006001100E346600E200350E115.5175E104175E
3000--406600E240350E139200E130200E
The fuse size shown will permit transformer overloading by at least 133% of its self cooling rating. Fuse sizes meet the 12 times full load current for 0.1 seconds and 25 times full load current for 0.01 seconds inrush criteria.

Motor Starter Fuses

Maximum Motor Full Load Current Amp Rating For Full Voltage Start
Fuse R
Rating
Fuse Amp
Rating
10 Second
Start
3 Second
Start
2R702832
3R1004045
4R1305565
6R1708095
9R200125140
12R230165190
18R390250280
24R450330360
36R650500550