Is this Circuit Correct? Safe?
Is this Circuit Correct? Safe?
(OP)
In the attached document is the circuit safe that is the floor door switch and the hopper door switch as it's single channel on hardwire and the other channel is input to the plc to let the HMI know which switch is open.
The switches are Allen Bradley tongue switches red and safety rated but I thought both channels had to go to a safety controller or safety relay?
Also the way it's wired it breaks common power to the output card. Is that a safe design? I normally see a red safety contactor in front of motor loads and these are normal contactors and would not remove power if contactor is welded.
This is OEM equipment and only about 6 years old.
The switches are Allen Bradley tongue switches red and safety rated but I thought both channels had to go to a safety controller or safety relay?
Also the way it's wired it breaks common power to the output card. Is that a safe design? I normally see a red safety contactor in front of motor loads and these are normal contactors and would not remove power if contactor is welded.
This is OEM equipment and only about 6 years old.





RE: Is this Circuit Correct? Safe?
I'm not seeing the problem.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Is this Circuit Correct? Safe?
RE: Is this Circuit Correct? Safe?
RE: Is this Circuit Correct? Safe?
When the doors close, the controlled equipment may start. This may be OK or may be covered in part of the drawing that we don't see.
On the other hand that may be the preferred mode of operation.
Bill
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"Why not the best?"
Jimmy Carter
RE: Is this Circuit Correct? Safe?
RE: Is this Circuit Correct? Safe?