We build small deburring cells. The next one has two E-stops, one guard door with a tongue interlock, one PowerFlex 525 on the spindle and a pneumatic clamp. Standard PLC is a CompactLogix 5069-L306ER, nothing exotic.
Our usual panel shop quoted a 440R dual channel relay and two 100S contactors, a few hundred. The integrator the customer uses says put a Compact GuardLogix in, 5069-L306ERS2, "future proof", and quoted about ten times that.
I've priced both and read the ISO 13849 summary twice, and I still can't say what actually decides it. The customer's risk assessment says PLr d for the door and the E-stops.
Is PL d only reachable with a safety PLC? That's what the integrator implied. I don't believe it, but I can't argue it, am I missing something obvious?
What does the risk assessment say has to happen for each one? Door open and E-stop pressed, same response, spindle off and clamp released? Or different? That's the question, not the brand of the box. I've seen the same cell done three ways on three platforms and all three passed.
Same response for all three. Drop the contactors, STO on the 525, clamp goes to the safe state. No zones, no muting, nothing runs while the door is open.