Light curtain muting

Hi

We have a little problem. We have a conveyor going in to robot cell, but rolleys transported by conveyor are so little on material and what is even worse, there is lot of different types so one bar might be enough in different position that we have not been able to get reliable light curtain muting using photo cells.

So I tried to find references on is it possible to use any sensor, eg. inductive to mute without affecting safety category of light curtain? And if, what is possible reference to look at?

All examples and references are done with photo cells and no where could I find anything about permissible sensor types. I believe it would be enough if one can guide me to right IEC or similar standard used in EU.

Thanks.

In our experience we couldn't find the correct sensor either.
The general safety rule that we adhere to is to wire up our muting sensors to a sick flexisoft safety PLC.
The supply is 24VDC but here is the safety side it sends a pulse on this supply every 200ms. This is suffice to say that the sensor is monitored and cannot be bridged to supply.
Sensors we have used to date are mainly reflective monitored BUT as you mention I don't see why you can't use other types as long as there are 2.
Muting lamps are a must.

All examples and references are done with photo cells and no where could I find anything about permissible sensor types. I believe it would be enough if one can guide me to right IEC or similar standard used in EU.

Click to expand...

I will watch this thread for updates too.