G E Fanuc Problems!!!

CAN ANYONE HELP ME TROUBLESHOOT THIS OLD, BUT MOST NEEDED PLC??

NO "RUN" OR "OK" LIGHT. HAND HELD READS ONLY RAM CHECK OK

ROM CHECK OK

WAS TOLD TO START REPLACING THE MODUALS ONE AT A TIME ,OR THE E-CHIP IS BAD???

WAS ALSO TOLD THAT THE CO. THAT BURNT THE E-CHIP IS GONE AND THAT THE CORE PROGRAM IS NOT AVALIABLE???

I FIND IT HARD TO ACCEPT THAT THE CHIP IS BAD, BUT IT WILL BECOME VERY COSTLY TO START REPLACING MODULES FOR THAT AS WE ALL KNOW THEY ARE NON-REFUNDABLE. HELP !!!!

May help if you state which GE Fanuc, not all are old, and what the specific problem is.

Dang you Terry, I sound so condescending these days.

Its a 90-30 using a 331 cpu. no outputs working, but all inputs are working fine. hand held is lock-up reading ram check ok, rom check ok.

I would think that your fault table is full and the CPU has gone into run stop.
Clear your fault tables there are 2 PLC table and I/O then put it bach into run mode.

Ron said...
"Dang you Terry, I sound so condescending these days."

Ron... Ron... Ron... (da-do-ron-ron-ron da-do-ron-ron! Heh, heh, heh... sorry, Ron... just couldn't help it! It just sorta popped into my mind as I was saying it!)

There was absolutely nothing condescending about your question!

Craig might just as well have said...

HELP! OMG! HELP! I HAVE THIS CAR... IT DOESN'T SEEM TO WORK!!! OH... DEAR ME!!! WHAT, PRAY-TELL, IS WRONG WITH IT?

Craig...
Don't take offense... I was clearly being overly dramatic, just for the sake of my friend, Ron.

The normal power-up sequence for a 90-30 is for the OK LED to blink for a few seconds and then stay on steadily. The RUN LED indicates that the PLC is running its program.

If you have neither the OK nor the RUN LED, it could be power supply problems. It could be a bad power supply module or one of the I/O modules drawing excessive current.

Try removing all of the I/O modules and power up with only the CPU. If you successfully get through the bootup procedure, install the I/O modules one by one until it fails to boot. Before concluding that the last I/O module you installed is the one causing the problem, repeat the procedure with just the CPU and the I/O module that you suspect. If it powers up successfully under those conditions, it's probably the power supply module.

Once you can get it through the power-up phase, you should be able to clear any errors from the fault tables with the handheld.

I was waiting for Steve to part the clouds...

But, just curious Steve, it's been several years since 90-30 for me... isn't there an issue about slot-assignments and presence?

If you install an output module where the configuration file expects an input module or vice versa, the 90-30 will shut down on a "Configuration Mismatch" fault. However, a missing module is not a fatal error. If craig16134 decides to follow my advice, he needs to be careful not to mix up the modules.

thanks steve,

I did what you instructed and was able to get the run and ok light,but still no run condition. I can enter my values and pick points thru the hand held, but reply thru the plc? Do you think the e- chip is sour

I can enter my values and pick points thru the hand held, but reply thru the plc?

Click to expand...

I'm not quite sure what you mean. Were you able to get the RUN LED with all of the modules installed?

steve,

I cleared all faults on both tables and still no run condition. Disconected power to plc and reconected only to go back to ram check ok rom check ok. hand held is locked up again no run no go. tried new hand held with no luck. will not power up now with just the cpu in line. I checked line voltage and all is good.

steve,
I was able to get all lights with all modules installed but no responce from the plc once everything was loaded. I shut power down for about 3 mins. and powered up agian to only go back to no run, no go, hand held locked up to ram check ok, rom check ok. power to plc always good. this is a real head scratcher for me.

just powered up now with just cpu, and no run no ok led. hand held reads rom check ok ram check ok. no keystrokes working on hand held. how would i test for ex. current on a module??

craig16134 said:

I ... was able to get the run and ok light,but still no run condition. ...Do you think the e- chip is sour

Click to expand...

I assume you can get the RUN and OK LED's, but your program won't run? This sounds like the program is looking for an interlock. Maybe a safety interlock.
Do any of the output led's come on? If it has 24 volt controls, maybe the 24DC supply is bad.

The e-chip (EPROM or EEPROM) is not bad. These devices are very reliable compared to other devices. The handheld is telling you it's okay.

Are you sure the handheld is okay? Try it on another system.

Get a trial version of GE's software. The demo only runs for 4 days but that will give you a chance to download and save a copy of your program.

Follow Steve's advice carefully. He is an expert on these.

It sounds like it could be a bad power supply or baseplate.

There isn't any direct way to check a module's current draw. All you can do is to install them one at a time and see which one prevents the PLC from starting. In your case, if you can't get the OK LED with only a CPU module, your problem is quite likely the power supply.