FSR, VCE and Turbine Signal CSO

Hello everyone;

I am a plant operator. our plant running since 1978.

We have three types of turbomachine:
1- Turbogenerator MITSUBISHI control by MEGAC system
2- Two turbocompressors MS5002B (MARK 2)
3- Four turbocompressors MS5002C speedtronic( MARK 5 and 6)

I have a good knowledge in MARK 5 and 6, FSR and turbine control, GCV and SRV, etc.

I HAVE TWO QUESTIONS

1- I want to know the historic of turbine control begin with turbine signal CSO to VCE to FSR

2- We have a problem about the first one (turbogenerator). It doesn't running well since the last Inspection (2010). the last tests shows this parameters:

Turbine signal CSO = 65%, normal operation 65%

Combustion shell pressure = 4.5 bar, normal operation 5.5-6 bar

maximum speed 5900 tpm, normal operation 6000 tpm.

The breaker closed and the frequency not reaches 50 HZ so we can't synchronize it. (we have another 2 supply lines)

You might tell me where is the problem in MEGAC, instrumentations, or operation?

Where is the VCE or FSR in this old machine?

How the MEGAC system function??????????

You might need this information:

TURBINE
nominal speed 6047 tpm
nominal output 6220 KW

GENERATOR
nominal speed 3000 tpm
nominal output 7775 KVA, 0.8 PF
5500 V, 50HZ ,816 AMP

GENERATOR 3 phases 2 poles.

kind regards