First of all I am thankful to the contributors like CSA and others for sharing their experiences. I am a silent reader of this forum and found it very helpful. I want to express my gratitude for all the contributors and moderators for such a wonderful forum.
Mark V TMR system is installed on our site for Frame V gas turbines. Mark V was initially configured with <I> but in 2008 <I> was upgraded to HMI. Two gas turbines are installed at our site and each gas turbine has its own HMI in the GT compartment and we have one HMI in the control room for both the gas turbines for displaying data. The fuel used for the gas turbine is Natural Gas.
Our gas turbine system was working fine. During shutdown ground fault was observe on one of the gas turbine. The ground fault was troubleshooted. The ground fault did not disappear when we removed the power of the I/O cores. We decided to power down the Mark V panel. <R>, <S>, <T> and <C> cores were turned off from toggle buttons in <PD> core. The wires taking power to I/O cores were disconnected. We disconnected every wire going out of the TCPD card of <PD> core. The problem was still there. It was suspected that the other devices which are powered by 125VDC are the causing the ground fault problem. The breakers of each device (motors) etc were were turned off one by one but the fault still persisted. Our Mark V panel and Generator protection panel are getting the power from one breaker. The fuse of the Generator protection panel was removed but the problem still persisted. We decided to check the 125VDC batteries and its bus. The battery was leaked and its liquid was spilled out and was causing the ground fault problem. The liquid was cleaned and the ground fault problem was rectified.
After maintenance the Mark V panel was powered up. All the cores attained A7 status. After that the gas turbine was started successfully. After a week the S core was found in A6 status. Following alarm log was found
28-JAN-2015 15:54:54.718 T1 1 Q 0144 ALM COMPRESSOR INLET THERMOCOUPLES DISAGREE
28-JAN-2015 15:54:54.718 T1 1 Q 0407 ALM COMP INLET TEMP TC TROUBLE
28-JAN-2015 15:54:54.718 T1 1 Q 0408 ALM GAS FUEL TEMPERATURE HIGH SPREAD
28-JAN-2015 15:54:56.000 T1 1 T 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:54:57.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:54:58.000 T1 1 R 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:54:58.000 T1 1 R 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 15:54:58.000 T1 1 T 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 15:54:59.000 T1 1 C 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:54:59.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:55:28.000 T1 1 S 1251 DIA TCQA 4-20mA output disagrees w/ref CH.B
28-JAN-2015 15:55:29.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:55:30.000 T1 1 S 0312 DIA LCC: Processor re-booted independently
28-JAN-2015 15:55:30.000 T1 1 S 0326 DIA LCC No arcnet communication with <T>
28-JAN-2015 15:55:30.093 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:55:34.000 T1 0 T 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:55:34.000 T1 0 R 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:55:35.000 T1 0 C 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:55:36.000 T1 0 S 0312 DIA LCC: Processor re-booted independently
28-JAN-2015 15:55:36.000 T1 0 S 0326 DIA LCC No arcnet communication with <T>
28-JAN-2015 15:58:43.625 T1 0 Q 0087 ALM TURBINE INCOMPLETE SEQUENCE
28-JAN-2015 16:00:58.343 T1 1 Q 0099 ALM TURBINE AIR INLET TROUBLE
28-JAN-2015 16:01:01.500 T1 0 Q 0397 ALM EX2K OPERATOR SELECTED EXCITATION OFF
28-JAN-2015 16:04:15.406 T1 1 Q 0117 ALM HYDRAULIC PROTECTIVE TROUBLE
28-JAN-2015 16:04:16.468 T1 1 Q 0167 ALM GAS RATIO VALVE POSITION SERVO TROUBLE
28-JAN-2015 16:04:18.000 T1 1 R 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:04:18.000 T1 1 R 1697 DIA TCE1 TMR check trouble, ETR2
28-JAN-2015 16:04:18.000 T1 1 T 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:04:18.000 T1 1 T 1697 DIA TCE1 TMR check trouble, ETR2
28-JAN-2015 16:04:19.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 16:04:23.000 T1 0 T 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 16:04:25.000 T1 0 R 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 16:12:25.000 T1 0 R 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:12:25.000 T1 0 R 1697 DIA TCE1 TMR check trouble, ETR2
28-JAN-2015 16:12:25.000 T1 0 T 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:12:25.000 T1 0 T 1697 DIA TCE1 TMR check trouble, ETR2
All the cables and connectors were checked thoroughly and found OK. We decided to re-boot the core by the toggle switch in the <PD> core. The S core was initialized and successfully attained the A7 status.
After two three days again S core was found in A6 status. Alarm log for this period is given below
31-JAN-2015 13:49:40.000 T1 0 C 3785 DIA Voter mismatch, <S> DV_ERR
31-JAN-2015 14:01:31.218 T1 1 Q 0144 ALM COMPRESSOR INLET THERMOCOUPLES DISAGREE
31-JAN-2015 14:01:31.218 T1 1 Q 0407 ALM COMP INLET TEMP TC TROUBLE
31-JAN-2015 14:01:31.218 T1 1 Q 0408 ALM GAS FUEL TEMPERATURE HIGH SPREAD
31-JAN-2015 14:01:32.000 T1 1 C 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:01:32.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:01:34.000 T1 1 R 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:01:34.000 T1 1 R 1698 DIA TCE1 TMR check trouble, PTR1
31-JAN-2015 14:01:34.000 T1 1 T 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:01:34.000 T1 1 T 1698 DIA TCE1 TMR check trouble, PTR1
31-JAN-2015 14:01:35.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:01:59.000 T1 1 Q 0093 ALM COMMON IO COMMUNICATION LOSS
31-JAN-2015 14:01:59.750 T1 0 Q 0093 ALM COMMON IO COMMUNICATION LOSS
31-JAN-2015 14:02:04.000 T1 1 S 1251 DIA TCQA 4-20mA output disagrees w/ref CH.B
31-JAN-2015 14:02:05.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:02:06.000 T1 1 S 0312 DIA LCC: Processor re-booted independently
31-JAN-2015 14:02:06.000 T1 1 S 0324 DIA LCC No arcnet communication with <R>
31-JAN-2015 14:02:07.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:02:11.000 T1 0 R 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:02:11.000 T1 0 T 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:02:12.000 T1 0 C 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:02:15.000 T1 0 S 0312 DIA LCC: Processor re-booted independently
31-JAN-2015 14:02:15.000 T1 0 S 0324 DIA LCC No arcnet communication with <R>
The core was again re-booted and again it attained the A7 status successfully. Keeping in view 0325 diagnostic alarm we decided to change the LCC card as our first step if the core is found stuck in A6 status again.
Two weeks later again the S core was found stuck in A6 status. The log of this time is given below
14-FEB-2015 17:19:22.593 T1 1 Q 0144 ALM COMPRESSOR INLET THERMOCOUPLES DISAGREE
14-FEB-2015 17:19:22.593 T1 1 Q 0407 ALM COMP INLET TEMP TC TROUBLE
14-FEB-2015 17:19:22.593 T1 1 Q 0408 ALM GAS FUEL TEMPERATURE HIGH SPREAD
14-FEB-2015 17:19:24.000 T1 1 T 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:19:24.000 T1 1 R 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:19:26.000 T1 1 R 1698 DIA TCE1 TMR check trouble, PTR1
14-FEB-2015 17:19:26.000 T1 1 T 1698 DIA TCE1 TMR check trouble, PTR1
14-FEB-2015 17:19:27.000 T1 1 C 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:19:56.000 T1 1 S 1251 DIA TCQA 4-20mA output disagrees w/ref CH.B
14-FEB-2015 17:19:58.000 T1 1 S 0312 DIA LCC: Processor re-booted independently
14-FEB-2015 17:19:58.000 T1 1 S 0326 DIA LCC No arcnet communication with <T>
14-FEB-2015 17:20:02.000 T1 0 C 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:20:03.000 T1 0 R 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:20:05.000 T1 0 T 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:20:05.000 T1 0 S 0312 DIA LCC: Processor re-booted independently
14-FEB-2015 17:20:05.000 T1 0 S 0326 DIA LCC No arcnet communication with <T>
While we were checking the status on the display of LCC we decided to check the I/O status of the cards. As we opened the door of the core the S core attained the A7 status. We were quite amazed. Just to check we again closed the door with force the S core initialized. The we opened the door again and just tapped on the left side of keypad the (S core was in A7 status at this time) S core initialized once again. The S core attained the A7 status but it was giving following errors on the display
• 2 DCC errors
• Missing I/O Card
• I/O CFG errors
We reinitialized the core from the push button in the S core. The S core again attained the A7 status but again these errors were shown. We re-booted the core from the toggle switch in the <PD> core and the S core attained A7 status with no errors.
It is worth mentioning here that the ground fault has again appeared on the Mark V.
By keeping in view the above behavior can anyone suggest what the actual problem is?
We are planning to change the LCC card and check the cables and connectors once again. Are we on right track ?
I want to mention one more thing. This time we are getting two diagnostic alarms of S core which is still persisting.
• D273 IOMA power supply out of limits P15
• D274 IOMA power supply out of limits N15
We have checked the diagnostic counters. P15 and N15 were in their limits (15 +-0.75V). P5 was not in the limit 4.75 to 5.25V. P5 was showing 5.62V. We are also planning to rectify this by adjusting R29 potentiometer on TCPS card.
When P15 and N15 are in their limits but still the alarm is displayed on HMI can we deduce that we have faulty DCC card?
Please let me know if any additional information is required.
Mark V TMR system is installed on our site for Frame V gas turbines. Mark V was initially configured with <I> but in 2008 <I> was upgraded to HMI. Two gas turbines are installed at our site and each gas turbine has its own HMI in the GT compartment and we have one HMI in the control room for both the gas turbines for displaying data. The fuel used for the gas turbine is Natural Gas.
Our gas turbine system was working fine. During shutdown ground fault was observe on one of the gas turbine. The ground fault was troubleshooted. The ground fault did not disappear when we removed the power of the I/O cores. We decided to power down the Mark V panel. <R>, <S>, <T> and <C> cores were turned off from toggle buttons in <PD> core. The wires taking power to I/O cores were disconnected. We disconnected every wire going out of the TCPD card of <PD> core. The problem was still there. It was suspected that the other devices which are powered by 125VDC are the causing the ground fault problem. The breakers of each device (motors) etc were were turned off one by one but the fault still persisted. Our Mark V panel and Generator protection panel are getting the power from one breaker. The fuse of the Generator protection panel was removed but the problem still persisted. We decided to check the 125VDC batteries and its bus. The battery was leaked and its liquid was spilled out and was causing the ground fault problem. The liquid was cleaned and the ground fault problem was rectified.
After maintenance the Mark V panel was powered up. All the cores attained A7 status. After that the gas turbine was started successfully. After a week the S core was found in A6 status. Following alarm log was found
28-JAN-2015 15:54:54.718 T1 1 Q 0144 ALM COMPRESSOR INLET THERMOCOUPLES DISAGREE
28-JAN-2015 15:54:54.718 T1 1 Q 0407 ALM COMP INLET TEMP TC TROUBLE
28-JAN-2015 15:54:54.718 T1 1 Q 0408 ALM GAS FUEL TEMPERATURE HIGH SPREAD
28-JAN-2015 15:54:56.000 T1 1 T 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:54:57.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:54:58.000 T1 1 R 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:54:58.000 T1 1 R 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 15:54:58.000 T1 1 T 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 15:54:59.000 T1 1 C 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:54:59.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:55:28.000 T1 1 S 1251 DIA TCQA 4-20mA output disagrees w/ref CH.B
28-JAN-2015 15:55:29.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:55:30.000 T1 1 S 0312 DIA LCC: Processor re-booted independently
28-JAN-2015 15:55:30.000 T1 1 S 0326 DIA LCC No arcnet communication with <T>
28-JAN-2015 15:55:30.093 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 15:55:34.000 T1 0 T 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:55:34.000 T1 0 R 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:55:35.000 T1 0 C 0325 DIA LCC No arcnet communication with <S>
28-JAN-2015 15:55:36.000 T1 0 S 0312 DIA LCC: Processor re-booted independently
28-JAN-2015 15:55:36.000 T1 0 S 0326 DIA LCC No arcnet communication with <T>
28-JAN-2015 15:58:43.625 T1 0 Q 0087 ALM TURBINE INCOMPLETE SEQUENCE
28-JAN-2015 16:00:58.343 T1 1 Q 0099 ALM TURBINE AIR INLET TROUBLE
28-JAN-2015 16:01:01.500 T1 0 Q 0397 ALM EX2K OPERATOR SELECTED EXCITATION OFF
28-JAN-2015 16:04:15.406 T1 1 Q 0117 ALM HYDRAULIC PROTECTIVE TROUBLE
28-JAN-2015 16:04:16.468 T1 1 Q 0167 ALM GAS RATIO VALVE POSITION SERVO TROUBLE
28-JAN-2015 16:04:18.000 T1 1 R 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:04:18.000 T1 1 R 1697 DIA TCE1 TMR check trouble, ETR2
28-JAN-2015 16:04:18.000 T1 1 T 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:04:18.000 T1 1 T 1697 DIA TCE1 TMR check trouble, ETR2
28-JAN-2015 16:04:19.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
28-JAN-2015 16:04:23.000 T1 0 T 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 16:04:25.000 T1 0 R 1698 DIA TCE1 TMR check trouble, PTR1
28-JAN-2015 16:12:25.000 T1 0 R 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:12:25.000 T1 0 R 1697 DIA TCE1 TMR check trouble, ETR2
28-JAN-2015 16:12:25.000 T1 0 T 1696 DIA TCE1 TMR check trouble, ETR1
28-JAN-2015 16:12:25.000 T1 0 T 1697 DIA TCE1 TMR check trouble, ETR2
All the cables and connectors were checked thoroughly and found OK. We decided to re-boot the core by the toggle switch in the <PD> core. The S core was initialized and successfully attained the A7 status.
After two three days again S core was found in A6 status. Alarm log for this period is given below
31-JAN-2015 13:49:40.000 T1 0 C 3785 DIA Voter mismatch, <S> DV_ERR
31-JAN-2015 14:01:31.218 T1 1 Q 0144 ALM COMPRESSOR INLET THERMOCOUPLES DISAGREE
31-JAN-2015 14:01:31.218 T1 1 Q 0407 ALM COMP INLET TEMP TC TROUBLE
31-JAN-2015 14:01:31.218 T1 1 Q 0408 ALM GAS FUEL TEMPERATURE HIGH SPREAD
31-JAN-2015 14:01:32.000 T1 1 C 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:01:32.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:01:34.000 T1 1 R 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:01:34.000 T1 1 R 1698 DIA TCE1 TMR check trouble, PTR1
31-JAN-2015 14:01:34.000 T1 1 T 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:01:34.000 T1 1 T 1698 DIA TCE1 TMR check trouble, PTR1
31-JAN-2015 14:01:35.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:01:59.000 T1 1 Q 0093 ALM COMMON IO COMMUNICATION LOSS
31-JAN-2015 14:01:59.750 T1 0 Q 0093 ALM COMMON IO COMMUNICATION LOSS
31-JAN-2015 14:02:04.000 T1 1 S 1251 DIA TCQA 4-20mA output disagrees w/ref CH.B
31-JAN-2015 14:02:05.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:02:06.000 T1 1 S 0312 DIA LCC: Processor re-booted independently
31-JAN-2015 14:02:06.000 T1 1 S 0324 DIA LCC No arcnet communication with <R>
31-JAN-2015 14:02:07.031 T1 1 Q 0000 ALM DIAGNOSTIC ALARM <C><Q>
31-JAN-2015 14:02:11.000 T1 0 R 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:02:11.000 T1 0 T 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:02:12.000 T1 0 C 0325 DIA LCC No arcnet communication with <S>
31-JAN-2015 14:02:15.000 T1 0 S 0312 DIA LCC: Processor re-booted independently
31-JAN-2015 14:02:15.000 T1 0 S 0324 DIA LCC No arcnet communication with <R>
The core was again re-booted and again it attained the A7 status successfully. Keeping in view 0325 diagnostic alarm we decided to change the LCC card as our first step if the core is found stuck in A6 status again.
Two weeks later again the S core was found stuck in A6 status. The log of this time is given below
14-FEB-2015 17:19:22.593 T1 1 Q 0144 ALM COMPRESSOR INLET THERMOCOUPLES DISAGREE
14-FEB-2015 17:19:22.593 T1 1 Q 0407 ALM COMP INLET TEMP TC TROUBLE
14-FEB-2015 17:19:22.593 T1 1 Q 0408 ALM GAS FUEL TEMPERATURE HIGH SPREAD
14-FEB-2015 17:19:24.000 T1 1 T 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:19:24.000 T1 1 R 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:19:26.000 T1 1 R 1698 DIA TCE1 TMR check trouble, PTR1
14-FEB-2015 17:19:26.000 T1 1 T 1698 DIA TCE1 TMR check trouble, PTR1
14-FEB-2015 17:19:27.000 T1 1 C 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:19:56.000 T1 1 S 1251 DIA TCQA 4-20mA output disagrees w/ref CH.B
14-FEB-2015 17:19:58.000 T1 1 S 0312 DIA LCC: Processor re-booted independently
14-FEB-2015 17:19:58.000 T1 1 S 0326 DIA LCC No arcnet communication with <T>
14-FEB-2015 17:20:02.000 T1 0 C 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:20:03.000 T1 0 R 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:20:05.000 T1 0 T 0325 DIA LCC No arcnet communication with <S>
14-FEB-2015 17:20:05.000 T1 0 S 0312 DIA LCC: Processor re-booted independently
14-FEB-2015 17:20:05.000 T1 0 S 0326 DIA LCC No arcnet communication with <T>
While we were checking the status on the display of LCC we decided to check the I/O status of the cards. As we opened the door of the core the S core attained the A7 status. We were quite amazed. Just to check we again closed the door with force the S core initialized. The we opened the door again and just tapped on the left side of keypad the (S core was in A7 status at this time) S core initialized once again. The S core attained the A7 status but it was giving following errors on the display
• 2 DCC errors
• Missing I/O Card
• I/O CFG errors
We reinitialized the core from the push button in the S core. The S core again attained the A7 status but again these errors were shown. We re-booted the core from the toggle switch in the <PD> core and the S core attained A7 status with no errors.
It is worth mentioning here that the ground fault has again appeared on the Mark V.
By keeping in view the above behavior can anyone suggest what the actual problem is?
We are planning to change the LCC card and check the cables and connectors once again. Are we on right track ?
I want to mention one more thing. This time we are getting two diagnostic alarms of S core which is still persisting.
• D273 IOMA power supply out of limits P15
• D274 IOMA power supply out of limits N15
We have checked the diagnostic counters. P15 and N15 were in their limits (15 +-0.75V). P5 was not in the limit 4.75 to 5.25V. P5 was showing 5.62V. We are also planning to rectify this by adjusting R29 potentiometer on TCPS card.
When P15 and N15 are in their limits but still the alarm is displayed on HMI can we deduce that we have faulty DCC card?
Please let me know if any additional information is required.