Power Fuses


Prime-MEC Power Fuses
Suitable choice for Transformer Protection, Condenser (Capacitor) Protection, Motor Protection


  • The HRC Power Fuses belong to the Prime-MEC series. It interrupts high currents before the first loop of fault current has reached its natural peak value and therefore cuts down the required withstand capacity of the associated equipment on the electric system.
  • Though small in size, it has a high breaking capacity and its enclosed type is suitable for use inside of the panel board.
  • PRIME MEC fuses are equipped with striker pins for trip indicators as well as for operating the related load break switches.
  • Link type fuse holder enables easy maintenance and high stability when replacing the fuses.
    With Fuse Checker, checking the conditions of a fuse in the panel board or by telecommunication is possible.(Optional)

Applied standards – IEC 282-1, DIN 43625, BS 2692, KSC 4612

Applications – Transformer protection

  • To protect against short circuit current in the secondary part of a transformer and fault current in the transformer circuit.
  • Condenser protection
  • To protect against fault current in the condenser circuit.
  • Motor protection
  • To protect against fault current in the motor circuit
  • Cable protection
  • Fault current protection secures the cable


LS Prime-MEC power fuses are designed to protect equipments from fault current such as short-circuit, and generally used for the protection the circuits of transformers, capacitors and motors they protect.
For further safety and reliability the elements inside of fuses are made of silver, and high quality quartzs and and ceramic are used for magnetic rods and tubes, respectively.
LS medium voltage vacuum contactors using LS vacuum interrupters manufactured with World class technology are type tested in LS PT & T that is accredited high power test lab by World class KOLAS.
To ensure the performance they, installed in a vacuum contactor, are tested according to IEC 60282-1 in LS PT & T that is accredited high power test lab by worldclass KOLAS.

Considerations in application

  • Power fuses are suitable for the protection from a short-circuit, Overload current will not protected.
  • Reset or re-use after blowing is not possible. Fuse reset or re-use is not possible after fused are blown out.
  • When the fuses are selected, the inrush currents arising from the starting transformers, motors, capacitors should be considered.
  • When the fuses are selected, their usage and circuit requirements should be considered.
  • For the purpose of protection from the fault current below the lowest interrupting current of the fuse it is desirable to replace it with a fuse having lower interrupting rate or add other overcurrent relay in series.
  • Withstand voltage of the circuit should be higher than that of a fuse that protects it.
  • If possible, select the fuse whose rated current is much higher than the load current. The rated current not sufficiently exceeding the normal current of the load may cause reduction in the service life.
  • Replace all three fuses in case of blowing in a fuse.


Voltage(kV) Fuse link type Rated current(A) Transformer
Fuse holder type
Single phase Three phase
3.6kV 7.2kV 3.6kV 7.2kV
3.6/7.2kV LFL-3/6G-5B 5 4~8 8~16 6.7~14 13~28 LFH-6G-D1HB
LFL-3/6G-10B 10 6~13 13~25 11~22 21~44
LFL-3/6G-20B 20 15~31 30~62 25~53 51~107
LFL-3/6G-30B 30 21~42 40~84 35~73 70~145
LFL-3/6G-40B 40 40~82 80~165 69~143 137~286
LFL-3/6G-50B 50 49~102 98~204 85~177 170~354
LFL-3/6G-60B 63 66~137 132~275 114~238 229~476
LFL-3/6G-75B 75 68~165 134~330 117~285 233~751
LFL-3/6G-100B 100 128~220 256~440 222~381 443~762
LFL-3/6G-125B 125 151~275  302~550  261~476 522~952 LFH-6G-D2HB
3.6kV LFL-3G-160B 160 211~352 365~610
LFL-3G-200B 200 265~440 459~762
7.2kV LFL-6G-160B 160 426~704 735~1220 LFH-6G-D2HB
LFL-6G-200B 200 437~880 755~1520
24kV LFL-20G-5B 5 20~43  36~75 LFH-20G-D2HB
LFL-20G-10B 10 43~90 75~157
LFL-20G-20B 20 99~206 172~358
LFL-20G-30B 30 149~310 258~538
LFL-20G-40B 40 267~557 464~965
LFL-20G-50B 50 345~719 598~1246
LFL-20G-60B 63 430~897 745~1554
LFL-20G-75C 75 580~1145 1000~1983
LFL-20G-100C 100 923~1527 1600~2645
LFL-20G-125B 125 1364~1908 2362~3304
LFL-20G-160B 160 2125~2443 3680~4232
LFL-20G-200B 200 2650~3050 4593~5287