In mk5 is there a list all diagnostic alarms? Where I find?

How do we fix the following alarm:
[tcca status s page xmit failure ]

What does it mean the number 1 in the following alarms:
[tce1 power supply out of limits, p15]
[tcd1 contact input #39 failure]

 

Every Mark V operator interface has a file called ALARM.LST in the F:\UNIT1 directory. This ASCII text file should list every alarm, Process and Diagnostic, in the Mark V panel it was produced for.

Some operator interfaces have ASCII text files called HELP_QD.DAT and HELP_BD.DAT. They may be in F:\UNIT1, or F:\UNIT1\PROM, or they could be in any folder since they are not required for operation of the Mark V or the operator interface.

The first file is for <Q> (<R>, <S>, and <T>) Diagnostic Alarms, and the second is for <B> (<C> and <D>) Diagnostic Alarms. The files are called "help" files and have some very cryptic procedures for most, but not all, of the alarms.

One thing to know about these help files is that they were written for a specific version of PROMs and were not updated over the years to reflect every version of PROMs and Mark V panel produced. They are better than nothing, though.

The first alarm has been covered many times before on control.com, and can be found using the 'Search' feature at the top of every page. Basically, it is trying to indicate there is a problem with communications between the Mark V and an EX2000 exciter regulator/control system. If your unit does not have an EX2000 and the alarm dithers (is annunciated, then goes to status "0", and comes and goes intermittently), then this alarm is a nuisance alarm, and GE's fix is to upgrade the PROMsets to alleviate the alarm.

If your turbine has an EX2000 exciter regulator and this alarm is annunciated, then it's an indication of a problem with the StageLink (coaxial cable, and/or fiber optic hub and fiber optic cable if present) between the Mark V and the EX2000, or the termination resistors in use in the StageLink segment, or the card in the EX2000 that has the BNC connector for the StageLink communications with the Mark V. (Status S is the term for the communications protocol which is used by the Mark V and its associated EX2000 exciter regulator to communicate over the StageLink between them.)

The number "1" in the two alarms in the second question refer to the "first" TCDA card in the IONET link from the indicated processor (which you didn't provide). For example, if the alarm were being annunciated for <S> then the alarm is indicating that the circuitry associated with Contact Input #39 on the TCDA card in <QD1> in Loc. 2 is exhibiting a problem.

Usually this particular alarm is annunciated when there is a high induced AC voltage on the contact input cabling (because of poor signal level separation used during construction). But, that's not the only reason; it could be a failed circuit on the TCDA card.

TCE1 refers to the first TCEA card in the <P> core, in Loc. 1. You should probably check the fuses on the card before replacing the card.

Before you or anyone asks, I don't have a copy of the help files to send anyone. Perhaps some kind soul who is reading this thread will let us know they are willing to send the file(s) if you post your email address.

 

IN F: open ALARM.DAT
Scroll down to QD alarms and find alarm #.

eg.
QD 1737 TCE1 Power supply out of limits, P15
CD 838 TCD1 Contact input #39 failure

Then open HELP_QD.DAT and find the alarm #. It should give you a description of the cause and the action to take eg.

1737 ;TCEA Power supply out of limits, P15
1609 ;TCEA Power supply out of limits, P15
1481 ;TCEA Power supply out of limits, P15

CAUSE The TCEA P15V is out of limits .

EFFECT Could cause speed sensing to malfunction.

ACTION Replace the TCEA board .


800-895 ;TCDA Contact input #<nn> failure (<nn> = 1-96, inclusive)
592-687 ;TCDA Contact input #<nn> failure (<nn> = 1-96, inclusive)

CAUSE A component has failed within the indicated input signal processing circuit (#<nn>) on the TCDA card in the QD (or CD) core.

This fault condition can be detected as soon as the component failure occurs, regardless of the state of the contact input on the terminal board (DTBA/B).

Note 1: This fault only applies to component failures on the TCDA. Hardware faults along cables JQ or JR, or on the terminal boards themselves cannot normally be detected.

Note 2: A BATREF failure, although causing all TCDA inputs to fail, is detected separately and will not produce these alarm messages. (see below)

Note 3: Noisy contact inputs (with superimposed AC, for example) may also cause these diagnostic alarms to occur. Older TCDA cards are more susceptible to noise than the newer surface-mount TCDA design.

EFFECT While this alarm is present, the indicated input circuit will not be able to detect the actual state of the contact input on the terminal board. Furthermore, the signal state returned by the TCDA for this input will be unpredictable.

ACTION Replace the affected TCDA card. However, if noise on the TCDA contact inputs is the problem, find a way to filter the noise so that it is not introduced into the DTBA/DTBB terminal boards.

 

MPAC is more correct about the alarm text file name. ALARM.DAT is the ASCII text file which lists Process- and Diagnostic Alarm text messages and drop numbers.

ALARM.LST is a file that is created by running the Alarm Listing executable (ALARM_L.EXE) and is the listing of Process Alarms, drop numbers, and the logic signal which is associated with the alarms.

My apologies for describing the wrong file. (Too many files on the Mark V operator interfaces.)