Auto Sync Lock out alarm


Thread Starter


Dear CSA and Friends,

I request help and suggestions for solving this problem

MKV Speedtronic Panel Indicates - Alarm- Auto Sync Lock out, even though turbine is under Maintenance - not running.<pre>
In prevote data L30AS1 shows r=1, s=1, t=1
L30AS1 shows r=0, s=0, t=0

Diagnostic alarm - 1722 - R, S, T, = TCE1 Synch lockup, 25 relay failure.</pre>
I have checked all cables in coming and outgoing to PTBA and TGEB, TCTG cards and shows normal.

I have also checked all berg jumpers as indicated in the maintenance/application manuals and is OK. There is no visible sign of any component failure on the card.

Please advice.

Thanks and Best Regards,

Long time no hear from you. Last we did, you were going to report back about the results of your investigation into reported loss of power after fuel BTU content was found to have dropped significantly.

I don't have access to GEH-6195, The Mark V Application Manual, which I believe has some information in it about the two signals L30AS1 and L30AS2.

I also believe that if, as commonly happens on units "under Maintenance" the Bus (Running) PTs are isolated and their output to the Mark V goes to zero volts the Mark V will not allow synchronization--to a Bus with zero volts (a "dead bus"). Most times the alarm, 'Bus Undervoltage - No Auto Synch' will be annunciated, but I also recall seeing an Auto Synch Lockout annunciated at the same time.

Really, though, when a unit is "under Maintenance" it isn't capable of synchronization, so an Auto Synch Lockout is not a problem. The only time it's a problem when a turbine is shut down and "under Maintenance" is when someone is trying to simulate synchronization.... Is that what's happening--someone is trying to simulate synchronization when the unit is at zero speed and "under Maintenance"?

Otherwise, why is this Diagnostic Alarm and Auto Synch Lockout a problem when the turbine is shut down and "under Maintenance"? In other words, until you are ready to actually start and synchronize the unit why are these alarms a problem? (The Mark V generates a LOT of nuisance alarms when "under Maintenance" that most people ignore; these are but two of them.)