Malfunctioning ETM in Automation Direct PLC

I am having trouble with the ETM (Elapsed Time Meter) in the attached word doc.
Anybody ever have this kind of problem or know what's wrong with the ladder logic?

1. You don't need the NC of T15 in the timer's first line. But this would only have lost one scan each reset, probably not much of a problem.

2. It shoud have been 'ADDD' V5100 if you are accumulating a whole bunch of 1/10th hours. I'll assume that V5100 has '1` in it and you are just incrementing the double at V2164. Make sure to set it up as a double (LD K1, OUTD V5100 - which also ties up V5101).

3. Another way to increment V2164 (assuming you don't want to tie up V5101) is:

LDD K1 - this loads '1' into the bottom 16 bit word of the 32 bit accumulator and clears the upper 16 bit word.
ADDD V2164
OUTD V2164

4. Make sure that you aren't accidently using V2165 for anything. It's part of the double (V2164 = LSW, V2165 = MSW)

5. In your repeat sections make sure that ALL items (except for the V5100 if you are just using it to hold '1') are different including the one-shot bit (C152).

6. Finally remember this is a BCD number. If you are reading it as decimal then it will 'jump' in the transition of a digit from '9' to '0'. It will look like, in decimal, that it jumped 6 places instead of 1 (if only the rightmost digit changed.) In the jump from '99' to '100' it will appear to jump 66 places.

If you could post the code it would be more informative. Without running the program I cant see anything wrong with it. It seems likely that some other part of the program is stepping on your memory.

As Bernie pointed out, remove the NC T15 in the first line. TMRAs are not reset that way. Also, I'm assuming that you are using a K value of 3600 for the TMRA and not 360.

You don't need the C152 one-shot either. You can use the T15 output to do the addition. Also, try placing the logic that does the addition before the TMRA. This works because the T15's output is not reset at the end of the scan, it is reset when the T15's instruction is reevaluated.

Personally, I would just use a counter to keep track of the ETM value instead of doing the addition logic you have. Using a counter will place the logic to increment and reset the ETM value in one rung. If you need to keep track of a value larger than 9999 (the largest value a CNT will keep track of) use an Up Down Counter, it keeps track of a value up to 99999999.

Tark,

Both Berinie & you are correct in your evaluation of the presented code, however the fact that it's not efficent dosnt mean that it wont work as intended. He can brush up the code as suggested, but that dosnt explain the problem he's expierancing.

Bernie wrote:

"4. Make sure that you aren't accidently using V2165 for anything. It's part of the double (V2164 = LSW, V2165 = MSW)

5. In your repeat sections make sure that ALL items (except for the V5100 if you are just using it to hold '1') are different including the one-shot bit (C152)."

Somewhere in there lies the actual problem..

Actually I'm kind of betting on my #6.

Bernie, I didn't think the NC T15 was needed either (this program came with a new triplex pump station we had built and the panel shop tech was not quite sure what the problem is and has not been able to come back to fix it yet so I am doing my best, he is a AB guy and struggles a little with AD the first problem was not using 2 words with the accumulating timer address)

You are right V5100 has a 1 in it.
I will go ahead and double check for duplicate elements but I think you might be on to something with the BCD. I have had to insert a BIN with other programs to make it work right.

Tark, yes the K value in the TMRA15 has a K value of 3600.
I also wondered why the one-shot and why use V5100 instead of a K1.

Anyway thanks for all the good input I will be off work till next tuesday before trying again.

How do I attach the code as it is written, it is a pain the way I am doing it and I am going from memory, not good?

Zip the file up. If you're using windows XP, go up a level from the file, right click, send to winzip. You can attatch the zipped file to the forum.

CroCop said:

Zip the file up. If you're using windows XP, go up a level from the file, right click, send to winzip. You can attatch the zipped file to the forum.

Click to expand...

Actually the program is in a number of files with the same name and different extentions. You must select all thoes files and zip them togeather then you can post the zipped file. To attach a file to your post you must click on the button "attach files" and follow the instructions from there.

When posting a post with a file you must use "reply to thread" and not "quick reply".

bernie_carlton said:

Actually I'm kind of betting on my #6.

Click to expand...

Ok I'll go for that.

elevmike said:

Actually the program is in a number of files with the same name and different extentions. You must select all thoes files and zip them togeather then you can post the zipped file. To attach a file to your post you must click on the button "attach files" and follow the instructions from there.

When posting a post with a file you must use "reply to thread" and not "quick reply".

Click to expand...

Yep. I use DL PLCs quite often. That's why I said go up a level.

I always have a different folder for each PLC program when using DL & DirectSoft.

Well Bernie was correct, I couldn't wait till going to work next Tuesday so I went ahead and added a BIN (changing the BCD format to BINARY) and now it displays properly or seems to, time will tell for sure. I will also make the changes that everybody suggested as it will cleanup the program.

I guess I did not fully explain that the Triplex pump station is a remote site that we are communicating with by radio modem to a master PLC at the district office. We are using "Lookout" as our SCADA software to read data from the master PLC. The ETM problem was evident both at the remote site display panel and at the office SCADA host computer.
It amazes me how you guys can still come up all these good answers with minimal info and answer more questions than were asked. Thank you very much

Also I would zip up the code and post it if anybody was interested, (I am going to try this sometime anyway) the remote pump station has 3 Saftronic drives communicating via modbus to the PLC, 2 flowmeters, ultra-sonic level control, display panel setup to change speeds and on and off levels etc. approx 140 rungs in the program.

Thanks again

Ahh...so you were seeing the wrong value when it was displayed in Lookout?

If this is the case I would not use the BIN instruction in the program, leave it in BCD format. Instead tell Lookout that the value is BCD. Check how to format this in the I/O server help, but it would be something like V2164:B or V2164@BCD

Being able to answer these questions is a matter of 2 things: reading the manuals but more importantly remembering the answers to problems we ourselves have had. The 'numbers jumping around' reminded me exactly of my first impression of viewing BCD as if it were binary and seeing the jumps in value. Therefore I threw that in also, though the answer could easily have been one of the other things. Glad to be of help.

Tark, thanks for the tip on Lookout about telling it to read BCD I will certainly try this.
Also at the pump station panel the EZ touch display (if my memory is good its a EZ S6C-K)must have to be setup to know its reading BCD as it was not displaying correctly either.