440L Safety Light

[Armadillo852 25]

Guys and Gals, I have a problem with a 440l-PK0800YD set of safety lights. I have 3 conveyor legs in my way so I need to blank them out. I am using fixed blanking. I first pulled the legs out of the way to make sure my lights were lined up. Got the green light, every thing is good. I then put the legs back in place and of course I get the red light because they are there. All good so far. I would expect that. I then teach the fixed blanking with the legs in place, get the green light, all is good. Or so I thought. This is where the issue is. If I have the fixed blanking activated, it will flash between good and tripped (Red Light). I then get an e-stop. Nothing in the way, nothing running. I then put a piece of black tape on the receiver side where I want to be blanked. Same thing. For no reason, it will just trip and issue an e-stop. I have already sent a set back to AB to be replaced. Has anybody run across this issue, or is there something I can look for? Dip switch settings on the receiver end are: 1,2,3,4: ON position All others off.

[drforsythe 15]

I tried to find your light curtain number and I believe it is incomplete. I wanted to check your specific system because SOME light curtains do not allow you to blank the top or bottom beams. As a test for this, you could use your electrician's tape to blank an area in the center of the sticks. You would do this off of your machine (w/o conveyor legs in the way).

[Shiner 2]

How stable is the mounting environment. I had a set on a steel stamping press that needed blanking for a side dump that gave us tons of headaches until we fabbed up a solid mount instead of the flimsy ones that came with them. Once they stopped rattling around during a hit, the problem went away.

[Armadillo852 25]

Instead of the P, you need to use an R or a T. The P represents a pair when ordering. Neither the top nor the bottom is being blanked out. I already took tape and tried that to blank the area. Still get an estop. As far as mounting goes. These are in a 1/2" steel frame that is anchored to the floor with cement anchors. Very little vibration. It is a medical facility. But, I come from the automotive stamping industry, and yes, vibration is a big issue when trying to use light curtains with them. The strangest thing to me is the fact it works fine when I am not blanking anything out. Only when I try to blank something it faults.

[BobLfoot 301]

Just a wild guess here. I looked at the 440 App Profile sheet , I found here http://literature.rockwellautomation.com/idc/groups/literature/documents/pp/440lrt-pp001_-en-p.pdf and it gives me two key numbers that I see either 14mm (1/2 in) or 30mm (1 in) resolution. I wonder if your legs happen to be blocking 1/2 a resolution winow and playing havoc with the decision logic. If your resolution is 14mm try shifting 7mm laterally and see if things change. I know it's a wild idea , but I've seen crazier.

[Armadillo852 25]

Bob, Thanks for the reply. We are using 30mm blanking. Should have mentioned that. I tried moving 5mm at a time until I reached 30mm. Same problem. We had this issue before and sent the pair back to AB for replacement. Same thing. :( I think what I am going to do instead of messing with this issue is to move the conveyor legs. Then I can have full function and not mess with the blanking. I talked to mechanical Engineering and they said it was ok.