caterpillar generator 3412C

[shkoko2000]

first we have 3 cat. generators sync. with each other and with the national grid and controlled by woodward control system (EGCP-2) there is a problem at gen. 2 "reverse power alarm" so third party is maintained it by rewinding the excitor as they said that alarm due to insulation failure and when gen.2 came back we load it by load bank and reach the full load but the gen. not connected to system when we connected it again there is a new alarm "reverse KVAR"
note:we check all excitor loops.
what i can do?
and what is the reasons of this alarm?

 

[Jeff23spl]

I don't know much about generator but Reverse kvar would mean to me a capacitive load like powering a capacitor bank ?
Or a bad reading of the FP, can you have a phase order reversed between power and control unit ? I don't know if it use CT and transformer to read output power with low signals and one of them may make a phase shifting on the read order.

 

[BobB]

Reverse power (kilowatts) is directly related to speed and reverse var (kvar) is directly related to voltage. The reactive load if you like. Possibly connected up with a phase reversed and the EGCP2 sees it as reverse var?

 

[chop347]

Parameters & Calibration

If you can see you generator sharing properly there is always the chance the EGCP is putting out a false trip. (But rare).

I would download your parameters from all 3 controllers and use a program like examdiff to make sure nothing been changed.


Did use a external meter to prove that your PT & Ct are calibrated correctly?

From Manual 26174 EGCP-2 Engine Generator Control Package

Woodward 147
Calibration of Generator PTs and CTs
The Calibration menu of the EGCP-2 contains calibration adjustments for three
phase generator voltage and current. These calibration adjustments are labeled
as follows:

PT Phase A Scale
Calibrates the A phase generator PT input.

Menus Affected
Changes in the calibration set point will change the generator A phase voltage as seen on the Generator Status screen. Changing this value will also have an effect on generator kW and kVAR levels.

 

[shooter]

No it is NOT a insulation failure, it is a regulator failure or the reverse control is set too low, or maybe even a pickupcoil is wrong way around.