FLA on a medium voltage motor
FLA on a medium voltage motor
(OP)
We have a reconditioned NEMA motor - rated at 1750 HP 6000V 3 Ph 50 Hz (overseas application). The motor is about 730 ft from the MCC which is fitted with a soft start. The electrical system is supplied by 4 Hyundai generators rated at 6550 V 3 Ph 50 Hz.
The elelctric motor drives a large gas compressor which has the valves removed to allow it to operate without loaded condition.
When the site starts the motor, the SCR in the soft start burns out - we have replaced the softstart several times.The softstart is rated at 150 amps per microsecond, at the cutoff point before damaging the SCR's as advised by the equipment supplier, Motortronics.
Any advise on what may be happening in this system or method of corection appreciated. We are looking at installing "inductors" in series with the softstarts, but these will not be online when the softstart is bypassed.
Second question - the site are considering starting the motors "line to line" - is this recommended with a generator supplied power source.
The elelctric motor drives a large gas compressor which has the valves removed to allow it to operate without loaded condition.
When the site starts the motor, the SCR in the soft start burns out - we have replaced the softstart several times.The softstart is rated at 150 amps per microsecond, at the cutoff point before damaging the SCR's as advised by the equipment supplier, Motortronics.
Any advise on what may be happening in this system or method of corection appreciated. We are looking at installing "inductors" in series with the softstarts, but these will not be online when the softstart is bypassed.
Second question - the site are considering starting the motors "line to line" - is this recommended with a generator supplied power source.





RE: FLA on a medium voltage motor
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RE: FLA on a medium voltage motor
RE: FLA on a medium voltage motor
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One could check GaAs rectifiers also.