PZE X4P Safety Relay Y1 & Y2 Confusion

[Robatics1278]

Hello, all, I am new here and pretty new to PLC'S. Closest thing I have to PLC experience is with avionics. At my new job I am a welding engineer primarily in control of four Motoman MIG welding robots.

Anyway, the company bought a used Motoman NX100 and it arrived about a month ago. There has been a ton of wiring issues I've spent the last few weeks correcting. This last one is stumping me.

So the robot didn't come with light curtains so I ordered a set off eBay. They are 1000mm SICK 4000's. I hooked them up and get a flashing error on the curtain saying L2. Okay, L2 is an error code for invalid configuration of EDM. I look in the SICK manual and it says:

If you connect the contact elements to be monitored to the EDM input, then you must activate the option EDM in the CDS (Configuration & Diagnostic Software. If not, the device will show the error L2.

If you later deselect the EDM option, pin 6 of the system plug must not remain connected to 24 V.

I believe our light curtains do not have the EDM enabled and that is why I was getting error L2. Wire 6 on the light curtain was hooked to the Safety relay Y2. I removed wire 6 from the relay and the curtains started working.

Now the problem is that when we try to flip the positioner we get an external e stop error. It sounds stupid but if we shake the relay it goes away and lets us flip. Doing some reading here I see that Y1 / Y2 are for a reset button. I am thinking that the Motoman control or light curtains are looking for a handshake that each other is working?? Odd thing is I can look at the Input for light curtain clear while this e stop error is active and it is saying they are clear.

Also while this e stop error is active both channel lights are on, on the relay.

I tried to put a jumper in between Y1 & Y2 but no luck.

Am I right in thinking I need to fool the relay or control into thinking the EDM is working or what?

Some help would be really appreciated.

Attached are some diagrams.

Thank You

 

[plvlce]

Electronic Device Monitoring -- EDM -- is a way for the light curtain to verify that when it turns off its outputs, the connected safety device(s) actually interrupt the circuit as they should.

I have not worked with SICK curtains, but if CR4105 turns on and off when the LC are cleared/broken then you have things wired to match your configuration (ie if pin 6 is disconnected, EDM must be de-activated).

Based on the wiring diagrams shown, there is nothing further in the system that would care about EDM.

The fact that you report that shaking the relay allows you to run leads me to suspect the relay itself is failing (and failing 'safe' as it should). To verify this, check voltage at and across pins 13 and 14 on the relay when the issue is present.

With both channels of the relay on (as shown by the status indicators in your picture) you should have continuity across them and thus no voltage difference. If there is voltage on one side but not the other with the relay on, the relay is bad.

 

[Robatics1278]

Thank you very much for the response, plvlce. I will grab a meter and report back. Thank You

 

[Robatics1278]

Well, plvlce looks like you are on to something. Checked 13 and 14 with the error NOT present and got 24v on both pins. I then manually caused the error and rechecked, 24v on 13 and 0v on 14. Shook the relay and retested power on both 13 and 14 again. A new relay should be here Friday. I'll report back.

Thank again.

 

[dwoodlock]

I could be wrong......, but as I recall one channel is a 24v loop, and the other is a 0v loop, this is 13 & 14.

Been a couple years since I've been working with one of these.