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Comparison between Electro Permanent Lifting Magnet and Lifting Electromagnet



Comparison Item

Electro Permanent Magnet

(Electrically Controlled Permanent Magnet)



The source of magnetic

Permanent magnet material generate: NdFeB, AlNiCo

Electric current generate: current through spiral coil generate magnetic field.


Working State: excitation

The magnetic field generated by two kinds of permanent material act on workpiece at the same time.

Electromagnetic field generated by current act on workpiece.


Working State: demagnetization

The magnetic field of two kinds of permanent material cancel each other out, magnetic field does not act on workpiece

Blackout eliminate electromagnetic field.



Working without electricity, blackout or power supply line fault will not lose attraction force, absolutely safe.

Electricity can generate magnetic force in working process, it lose magnetic force as soon as magnetic chuck loss electricity, it’s not safe. If adopt battery as backup power, it can keep 10-30 mins in the case of electric control system with no fault (is related with battery capacity)



Attraction force is not affected by any natural and work factor in working process, reliability high.

Attraction force is affected by current and heating, has fluctuation, also the coil is easily burned, reliability low.


Durability and Maintainability

Permanent magnetic with no attenuation, magnetic module maintenance-free, durable, need no backup module, no wearing parts, low maintenance costs. Due to accidental impact may cause Internal component damage or cable breakage. Our electro permanent magnets and control systems have passed a million times magnetize /demagnetize life test.

Magnetic coils need to be replaced regularly, batteries need to be replaced regularly, need spare modules and backup power, much maintenance, high maintenance costs. Connecting cable parts (electromagnet and beam connections) using protective casing, unexpected impact may cause cable fracture, electromagnet loss magnetic.


Operating Cost

Lifting process does not consume energy, the energy consumption is extremely few, operating costs ultra-low. If a cycle is calculated at 10 minutes, every hour need electricity of 12 seconds (charge and back take 2 seconds every time), the maximum power 12.8KW, 8-hour working time, this model of electro permanent magnet yearly power consumption (calculated as 300 days) is 102.4 KWH (12 seconds x 8 hours x 300 days / 3600 sec / hour x 12.8KW = 102.4 KWH). If calculated as 1.5 RMB / KWH, the annual electricity consumption is 153.6 RMB. Basically without components maintenance and replacement.

Large power consumption, high operating costs. Based on usage, can choose model MW35-12069L/1, cold state power 8.5KW, at an average power of 6KW (considering hot state, power will decrease), 8-hour day, the electromagnet of 50% duty cycle, the annual consumption of electricity is 6KW x 50% x 8 hours x 300 days = 7200KWH, according to 1.5 RMB / KWH, the annual electricity consumption is 10,800 RMB. Components and batteries need to be replaced regularly.


Ratio of load weight to lifting appliance

Lifting appliance (including controllers, cable reels, etc.) total weight about 500KG. Compared to the crane which using lifting electromagnet, the lifting capacity of crane which using electro permanent lifting magnet increased by 0.8 tons.

Lifting appliance (including controllers, cable reels, etc.) total weight about 1300KG, crane load is much heavier than the load of using electro permanent lifting magnet.


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