150kVA ROTARY UPS FAILURE

[vmac100]

Gents,
I have a 150kVA HITEC rotary UPS that when synchronised to the busbar with another machine of the same make and rating does the following:
1. Takes up a large proportion of the connected load.
2. Pulls all the load to itself.
3. Drops the load and starts running on high frequency.
Do you have any idea of what the cause(s) of these may be?
HELP!!!

 

[dpc]

Did it used to work correctly and just start this behavior, or is this a new installation?

 

[vmac100]

DPC,
thanks for the reply.
It didn't just started this behaviour. The machine has been down though functional as it was not possible to synchronize it unto the vital load busbar with the other machines. And when it was eventually done, it dropped the load.
However, as at yesterday, it stopped taking any load permanently. It would take load for about a second and drop it.
Any ideas?

 

[aolalde]

Do you have the voltage regulators interconnected to share the reactive load?

I am assuming that electric motors turn the rotary unit, if the motors are combustion engines you will need additional control to share real power too.

See the following link for more details.

http://www.basler.com/php/download_page.php?section=regulation#PRS210

 

[vmac100]

Sorry, I had to take some time off.
DPC, the machine started this behaviour recently