Arrow 2 500 safety problem

[mihaicretu]

The problem is that I cannot align the machine because there’s a message on the control panel’s screen saying “Close operator door” even with the door closed. My first guess was that the safety interlock switch might be damaged so I’ve opened it and checked the 4 NC contacts and they are ok. I also checked that the 4 wires from the door contacts (2 from coil and 2 from key) enter the SIGUARD safety relay (3TK2825-2BB40) and the distributed I/O Siemens SIGUARD module (PM-D-F2), and I didn’t find any problem.
When I switched ON the main power switch, the safety relay on the door lock’s coil contacts had the Channel 1 / Channel 2 LEDs lit at startup and not lit when the message I mentioned was displayed on the panel. If, when the message was displayed and both LEDs not lit, I was manually forcing the coil to lock the door – though the coil had 24Vcc on command terminals, it was triggered and was unlocking the door – both LEDs on the channels input in the safety relay SIGUARD were lit. In this case the machine was starting.
The machine was not starting because, as far as I could tell, the coil needed to lose the 24Vcc command so the door would have been locked and the NC contacts closed, in this way the safety relay receiving both channels on positive pulse. In this case the machine would start (I’ve described above the situation when we forced the coil to lock the door and close the NC contacts).
The coil’s command signal’s drop to zero is from my point of view conditioned by one or more signals received by the PLC/Control computer from the machine – sensors, proximity switches, etc. Another possibility is that the module of the distributed I/Os of the machine which has as inputs the two contacts coming from the door’s key (the PM-D-F2 SIGUARD 3RK1903-1BB00) may be damaged. Since I do not have the logical diagrams or logical conditions of some machine commands such as locking/unlocking the door I cannot tell why the door’s coil doesn’t lock the door though the doors are closed.


Please give me a feedback.

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[JordanMach]

I know this is an old thread. I hate to bring back alive. But did you find out what was wrong? I think I am having the same issue. My machine is intermittently telling me to close the doors..... even when they are closed. Door switches are working. Machine signals are in the back saying doors are closed and what not. Only thing I havent messed with is the relay for the door lock. But the door wont lock until the machine sees the doors closed, or so I would think. So I dont think I am having issue with the Door lock or relay.

[meckardt55]

You need to include the control model, A2100????

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[JordanMach]

Yes. I thought all Arrow 2 machines had the A2100. Also, all the units he is talking about I have as well. The Siguard safety relay and what not. I actually figured out my issue. I had a bad "4DI" unit DI_05 for the door closed input. The Unit was recieving the signal, and showing the signal via the LED on it, but the control was not seeing the signal all the time. Wasnt too hard to figure out once I was able to find the input inside the control to see if the control was seeing it or not. I am still trying to figure out where in the software the string is that looks for door open then close between cycles. I just want to make sure its working properly But I know thats something Ill have to find on my own I think.

[meckardt55]

I think some had Fanuc controls and some had whatever the customer wanted to pay for and the engineering. So to assume that all had A2100DI controls could be incorrect. More info is always helpful.

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