Dear CSA and All,

I could calibrate the SRV/GCV in the recent past and now Calib page does not allow calibration.

Ours is a GE Fr5 MK6 control turbine. During an attempt to calibrate the SRV and GCV servos, under LVDT/R calibration page and while the calib. mode was selected to ON condition, the following error msg appears:- calibration mode bit was not set in channel "R", and could not achieve calibration mode for both SRV and GCV.

This msg appears for both Regulator#1 and Reg#2 calibration. What could be the problem?

Then, for stroking 65FP distillate fuel servo, I suppose, it can be done by forcing the value of FAL up and down to see the movement of servo valve with turbine in CRANK mode. Am I right? Kindly advice....Thanx.

 

You are missing the permissive. Did you remember to force the value of L3ADJx under Card Points ? Only one L3ADJx can be true at any time.

Other than forcing 65FP open or closed calibrating VC3 wont till you too much other than if the servo has failed or is locked. This is best tested by disabling the spark plugs and performing a false fire to make sure FQL follows the demand. It doesn't sound like you have LVDT's on VC3 but if you do you can temporarily reconfigure the regulator for LVDT feedback and manually position the fuel bypass valve. Just make sure to return the feedback to pulse rate.

If you do not have a 88HQ hydraulic pump then cranking the unit will provide hydraulic pressure to operate the fuel valves/IGV. Another option is temporally pipe the 88HR ratchet pump to provide hydraulic pressure. To do this a test manifold is needed to connect the output of the 88HR pump to the input of VR21 on the hydraulic manifold. (Check your PIDs). The setting of VR21 will need to be dropped to 500-600psi for the test otherwise the ratchet pump will trip on electrical overload.

 

Dear 309EGUY,

Thank U for replying to my post.

My reference was to SRV/GCV calib.with Mk6 control. On selecting the SERVO calib.page under slot5, REG#1 for SRV, with turbine running in crank mode and having selected on line and PW level 1, the L3adj goes to "logic 1" automatically. Then when "calib.On" is selected under Calib.page, the alarm "calib. bit set is NOT OK " comes ON. Anyway,now our turbine is running due to high load demand. I shall check/confirm the logic state of "L3adj1" during my next calib. attempt as advised by you and then come back to you.

Thanx a lot for ur response..