WHAT IS THE MEANING OF LETTERS IN GE MARK VI LOGICS.

QA MEANS LUBE OIL AND HQ MEANS HYDRAULIC OIL, LIKE ALL LETTERS MEANINGS I WANT TO KNOW. PLEASE TELL ME

 

This system goes way back to the original GE gas turbine controls, back even before Mark I SPEEDTRONIC. Since you are only asking about the letters, I assume you already know the numbers are from switchgear protective relay nomenclature.

I do not have the GE "bible" for this - I left it behind when I retired. (Before you go asking around for a copy of this bible, it was an internal GE document not published outside GE.) However, suffice it to say that by the time Mark VI controls appeared on the scene, most of the obvious meanings of the 2 letter coding had been used up and many of today's codes just reflect that it was an available code.

The main original codes for the first letter were:
Q = lube oil
H = hydraulic oil or high pressure shaft
G = governor or generator
N = speed
A = air
E = exhaust
L = low pressure shaft

The second letter can be even more obscure, with:
A = alarm
T = trip
being the main constants.

Sorry I can't be of more help on this. Your best current guides are the listings of the field devices in the Device Summary document and whatever nomenclature index GE may provide for the control.

 

Most Mark VIs (and Mark Vs for those of you reading this with Mark Vs) were provided with a file in the site-specific directory called LONGNAME.DAT. (Use Windows Explorer and search the hard drives of the HMI for this file to locate the exact directory/folder where it's located.)

This is an ASCII text file (which can be opened with Notepad or Wordpad) that is 97.451936% correct when it comes to the descriptions of GE signal names.

As otised says, there is some general rhyme and reason to most of the signal names, but not all of them.

If you don't have this file on your HMI, perhaps someone could post a copy of it from their site to a World Wide Location and then tell us how to access that location. Most of the LONGNAME.DAT files are fairly generic and not very unit-specific, so it's kind of a "one size fits all", take-what-you-get thing anyway. It's very rare that LONGNAME.DAT was edited to be unit-specific and 100% correct.

Hope this helps.

There are some other tips, hints, and tricks that can be useful, but most of them can be gleaned from reading the descriptions in LONGNAME.DAT. Look for the patterns, as with everything in life.

Just don't expect the patterns will always be repeated with 100% precision--especially with GE turbine control systems.

 

Dear Sir,

In Mark VI, I want ask about:
1. alarm/event with "Q" code, like:<pre>
23:03:19:109 G1 1 Q 0119 WHEELSPACE TEMP DIFFERENTIAL HIGH,</pre>
How we can check this alarm? (detail please).

2. In our plant (Frame 9), used 2 magnetic pick-up in flow divider. Now, one of the flow magnetic pick-up was not good. It can be effect for trip? Because it was 3 times the plant trip, after this magnetic pick-up trouble. (the alarm was "Loss of Flame Trip")

3. We not have data historian. Please tell us what equipment for this data historian and specification of these part?

Thank you

 

Dear Sir,
kindly reply to this question.

>In Mark VI, what is the meaning for Q 0119:
>1. alarm/event with "Q" code, like:<pre>
>23:03:19:109 G1 1 Q 0119 WHEELSPACE TEMP DIFFERENTIAL HIGH,</pre>
>How we can check this alarm? (detail please).

 

If I didn't understand wrong, I'll try to explain.

In 9F machines we have 2 thermocouples at each point to measure wheelspace temperature.

If there is 50 degree deviation between these two thermocouples,
It produces "WHEELSPACE TEMP DIFFERENTIAL HIGH"

 

Q is the designation for RST cores. It is alarm number 119 in alarm.lst

you have exceeded the temperature limit between 2 wheelspace tc.

 

I don't presently have a copy of Legacy Toolbox or a dongle to use, but if I recall correctly you can use Legacy Toolbox to find the logic signal which drives Process Alarm Drop 119, then use the 'Finder' feature of Toolbox to navigate to the part of the application code where the logic signal is written to.

But, you should be able to look at the Wheelspace Temperature display on the HMI and determine which pair of Wheelspace T/Cs has the highest differential. (Each Wheelspace typically has two T/Cs, one on the left side of the unit and one on the right side of the unit; they should be virtually identical, presuming the two T/Cs are installed correctly and similarly and both are reading properly. It's virtually impossible for two properly and similarly installed T/Cs measuring the temperature in the same Wheelspace to read excessively different temperatures, especially when one considers that the turbine rotor wheels are spinning at shaft speed in the wheelspace, mixing the air in the Wheelspace being measured, and that wheelspaces are generally very small areas.)

You can probably use the Help feature of Toolbox to determine how to troubleshoot any Process Alarm. Or, perhaps someone who has more recent experience with Legacy Toolbox or access to a PC with a copy of Legacy Toolbox installed can provide specific, step-by-step instructions on how to troubleshoot a Process Alarm.

If I recall correctly, there might be a Legacy Toolbox Menu bar selection under 'View' called 'Alarms'. So, if you click on View | Alarms, then find Alarm Drop 119, you might even be able to double-click on the drop number or the logic signal associated with Alarm Drop 119, and have Legacy Toolbox take you to where the signal is written to in application code.

Lastly, the "Q" refers to a Process Alarm that is generated in "Q", which usually implies <R>, <S>, and <T> in TMR (Triple Modular Redundant) Speedtronic turbine control panel.

 

The HMI should be very revealing of the TC which is causing the problem. TCs that are failing are pretty obvious. It may not be the tc though, I would clean all connections. GE was very good at ensuring mistakes can be prevented. The nuts on the TC wire are even a different size.

The TC can be changed on-line. A Good/Great set of insulated gloves will be required. Ensure you have a new compression nut and ferrul for the new TC. I do not recommend attempting to remove the entire connection, just the compression joint will suffice. Mark the TC at the compression fitting with a permanent marker before removal and ensure the new TC is installed to the same depth.

 

Thank you Sir.
Now, I can find out that alarm with ":Q: code.

I want ask again, another alarm/event with "E" code, (in Mark VI Speedtronic)like:

E1_P1031 M PSS DESELECTED

How we find out and trouble shooting event with "E" code ?

And, We not have data historian system. Please tell us what equipment for this data historian and specification of these part?

Thank you.

 

Wow.

E1 is likely the generator exciter regulator. I don't know what the M in M PSS means, but PSS probably means Power System Stabilizer.

GE's version of Historian is a separate, standalone PC running MS-Windows, TCI (a proprietary GE application), and OSI PI software. It will have a couple of Ethernet cards for the UDH and PDH to connect to the turbine and exciter and the other PCs and network equipment.

While it can be useful, it usually takes quite a lot of configuration and someone at site must spend months getting familiar with PI and the configuration of all the data points.

And, then that person usually peddles their experience to another employer for a job that pays more money and then no one at site can use the Historian after the one person who's familiar with it leaves.

 

Thank you Sir.