VersaMax communication woes

[ualm]

Hello all,

I'm having a bit of trouble with our GE Fanuc Versamax PLCs. We currently have a IC200UDR164 PLC with a Ethernet-to-RS232 module. Communication is through the serial port on Port1 and Ethernet on Port2.

Everything worked fine for most of our PLCs, but a couple of them suddenly stopped communicating on Port2 in Machine Edition when an attempt to program the PLC was made. Our standard procedure is to then use Port1 to re-establish connection in these cases. However, Port1 was also non-responsive (ie. going online times out). None of the PLC lights were blinking either (PWR and OK were solid green).

Subsequent attempts to use known good cables/computers, as well as power cycling and letting the supercap discharge over multiple days did not help either. The Ethernet module was even removed to eliminate it as a potential source of problems.

Does anyone have any suggestions on what I should try next?

Thanks

 

[Steve Bailey]

Multiple PLCs suddenly becoming non-responsive suggests to me a problem with the programming computer rather than the PLC.

 

[ualm]

Multiple PLCs suddenly becoming non-responsive suggests to me a problem with the programming computer rather than the PLC.

That's what I had thought too, but moving the PLCs around to known good computers (and vice versa) didn't produce any favorable results.

edit: I should also say that this is also a training environment with multiple computers and PLCs.

 

[Steve Bailey]

Forgive me for mentioning the obvious, but are these PLCs fitted with batteries and if so did you remove the battery when you powered down?

Does your computer have a real COM port or are you using a USB/serial converter? My USB/serial converter (from Staples) has LEDs on the transmit and receive lines that flash to indicate traffic on the lines. If I don't see either LED flash I know the PC isn't trying to communicate. If the LED on the transmit line flashes but not the one on the receive line, I know the PC is trying but getting no response from the PLC.

 

[ualm]

Forgive me for mentioning the obvious, but are these PLCs fitted with batteries and if so did you remove the battery when you powered down?

Does your computer have a real COM port or are you using a USB/serial converter? My USB/serial converter (from Staples) has LEDs on the transmit and receive lines that flash to indicate traffic on the lines. If I don't see either LED flash I know the PC isn't trying to communicate. If the LED on the transmit line flashes but not the one on the receive line, I know the PC is trying but getting no response from the PLC.

Hello Steve,

The PLCs are not outfitted with batteries and are reliant upon the supercapacitor instead. I've even taken off the small front-panel tabs to ensure that no one has installed a battery without my knowledge

The computers are luckily outfitted with real serial ports. Perhaps this is unlucky too, because there are no lights to indicate transmission from the port.

What's interesting is that Machine Edition times out when COM1 is selected, but will actually throw a 'cannot connect' error when other COM ports are chosen. Strange.

 

[ualm]

Oh, I should also say that I used GE's serial communication diagnostics program and fails to find any communication (with no error message either).

 

[Steve Bailey]

What's interesting is that Machine Edition times out when COM1 is selected, but will actually throw a 'cannot connect' error when other COM ports are chosen. Strange.

It makes sense to me. When you select COM1, ME tries to connect through it and times out due to lack of response from the PLC. When you select any other COM port, ME knows it isn't available and tells you it can't connect.

Do you happen to have one of the portable download devices? If so, try pulling the program and configuration out of a working VersaMax onto the portable and then download to the flaky one. Other than that, the next thing I would try would be to short out the capacitor.

Unless tech support has some other suggestions.

 

[ualm]

It makes sense to me. When you select COM1, ME tries to connect through it and times out due to lack of response from the PLC. When you select any other COM port, ME knows it isn't available and tells you it can't connect.

Do you happen to have one of the portable download devices? If so, try pulling the program and configuration out of a working VersaMax onto the portable and then download to the flaky one. Other than that, the next thing I would try would be to short out the capacitor.

Unless tech support has some other suggestions.

Hm. That's very true.

There may actually be an older portable S90-30 programmer from ages ago in another room around here. It has an old DB9 connector on it if I remember correctly, so I'll have to check to see if the DB9-RJ45 connector is the right gender on the DB9 side.

Shorting out the cap was actually my last course of action, since it requires removing the PLC from its current enclosure in order to access the supercap on the side We haven't contacted tech support yet... wanted to try all available options before giving them a call.

Thanks

 

[Steve Bailey]

I'm not sure the old 90-30 portable programmer would connect with a VersaMax. I think there's even a 90-30 firmware level above which they don't work.
I was referring to the IC690ACC990, but it appears that it doesn't work with the Micro20, Micro40 or Micro64 units.

 

[RussB]

See also: http://forums.ge-ip.com/showthread.php?p=74214#post74214