Paralleling to MV motors

[Padlock01]

Hi all, a colleague of mine is proposing paralleing two 750kW 6.6kV DOL motors on a conveyor (two gearboxes with a fluid couplings)me I am from the old school
I would have seperate breakers and contactors with interlocking between drives. Is there a regulation prohibiting the paralleling of large MV motors?

 

[LionelHutz]

Not that I know of. There are still installation rules that have to be followed, such as each motor will require its own overload protection. Is there a local electrical code for installations in South Africa? There must be some electrical code you follow and it will likely detail the requirements.

You obviously can't interlock between drives or both motors could not run at the same time.

 

[waross]

Years ago I saw two 3000 HP motors at 13.8 volts in parallel on the same breaker.
Each had independent protection.
The motors drove a crushing mill at a mine in Canada. We had six similar crushers.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Padlock01]

Naturally both drives would have independent motor protection relays, no there is no SA regulation other than SANS 10142-2 to my knowlege, Some Mining houses have their own specifications and guidelines for electrical designs on motor control, anyway thanks guys for your input.