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Deadman switch and door nothing connected

Deadman switch and door nothing connected

Deadman switch and door nothing connected

I have a equipment that have a safety door with a safety switch. I have a deadman switch. I want that when I have the deadman switch in my hand be able to open the door with machine run normally. I have a safety relay that all the e-stop is connected in serie on the safety relay. Can I connect the safetydoor switch in serie with all the e-stop?

RE: Deadman switch and door nothing connected

Can you? Sure. But the real question is "Would it be extremely unsafe to do such a thing?" The answer to that will vary with the piece of equipment... but anything with a door safety switch and three e-stops probably leans that answer to a resounding YES.

Dan - Owner

RE: Deadman switch and door nothing connected

It appears that it will work electrically. Your deadman switch should be normally open. Not sure about the safety aspect though. How is bypassing the door safety switch by holding a deadman switch going to protect the person(s)from harm?

RE: Deadman switch and door nothing connected

One of the great things about the Darwin award is that you do not have to apply or fill out any forms. If you qualify for the award then you are automatically entered and there is no need on your part to fill out an application form.

"Why not the best?"
Jimmy Carter

RE: Deadman switch and door nothing connected

I think the OP is wanting to bypass the door safety switch that would be NC while in operation with the deadman switch. Open the door and safety switch, close the deadman switch and proceed to hurt yourself. When the pain gets to be too much or you die, release the deadman switch, and stop the machine.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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RE: Deadman switch and door nothing connected

NC or NO describes the position of the switch when it is on the shelf, not when it is in operation.
"release the deadman switch, and stop the machine" That would be Normally Open, held closed when in use.

"Why not the best?"
Jimmy Carter

RE: Deadman switch and door nothing connected

i would do a risk assesment. ansi, iec, whatever your following with this machines, because it sounds like the scenario your describing is the person is in risk of death. Reason for a caged area is to keep people away from equipment that either a pinch point or crushing or some condition that would cause a big issue with the person living past the deadman switch dropping out.

RE: Deadman switch and door nothing connected

Hello Danygagne,

Just in case there is a language barrier, please explain why you would even want to bypass embedded safety features.

If you are encountering an operational issue, please explain what it is; there are numerous bigger picture thinkers here who may have suggestions for alternative approaches.

Remember: providing more information typically yields better answers.


"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

RE: Deadman switch and door nothing connected

We had a worker in the machine shop who would routinely "peek" thru the opened door of a milling center (typically when running the first article for new/revised machine programs). Arguably the worst possible time for defeating the door safety interlocks - twice he was injured when a machine crash sent shrapnel flying. After the second incident, he was asked to find other employment.

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