Recent content by Dopler

Good day. Have you tried running only the motor with load uncoupled? To isolate any mechanical load and measure motor current.

Good day. Factory Mutual Global have those procedures, in their data sheet number 2.81 FIRE PROTECTION SYSTEM INSPECTION, TESTING AND MAINTENANCE, you will find all that information. Data sheets are public documents, you can Google them, I copied the link...

When entering EP penthouse, there must be some porcelain bushings, inspect them, may be there could be somthing.

Have you verify high voltage cables? As I remember, those where isolated by isolating oil impregnated paper, the connecting device to EP field has a reservoir that has to be oil filled to have good isolation in cable. Hope this helps.

High rotor current could be the problem, from your explanation I infer that a step resistor is used for starting, verify correct connections in final short circuit contactors, does It has a rotor current amp? Verify against name plate. Carbon dust could be a problem also or a symptom, a problem...

Thanks to all, I will check this with our procurement people. Cheers

Many thanks now I have some numbers to contact. Cheers.

I wonder if some body knows the name of a company within UK to perform a short circuit and coordination study for an industrial facility. If so, I will appreciate. Cheers.

GE makes LCI, load commutated inverter, to be connected to a synchronous motor and have variable speed. Try http://www.geindustrial.com/cwc/products?pnlid=7&famid=13&catid=112&id=innovlci&lang=en_US

It is correct, PWM.

Input transformers for VFD are intended for some reasons, some are Voltage transformation, adequate voltage input for VFD Phase shifts, depending number of VFD pulses Electrical isolation, between power source and VFD Harmonic reduction, impedance between power source and VFD Fault current limit...

You may try http://www.americaninfrared.com/

Factory Mutual Global in their specification 5-20, also recommends power factor (dissipation factor) for bushings and windings, DGA for oil.

That is only for safety reasons, it is up to you to install it. Some times we install a disconnect switch near the motor, because it was not near the VFD, to perform hands on the motor with safety.

I hope that he has finish his education. Good thing.