Can the proximity switch of the on-site switch ball valve transmitter be replaced with a contact switch?
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Can the proximity switch of the on-site switch ball valve transmitter be replaced with a contact switch?
It’s possible, but if it’s intrinsically safe and explosion-proof, a safety barrier still needs to be added
Sorry, may I ask what I/P means?
It can’t be changed; the signal type has changed, so it doesn’t match the DCS
Replacing the proximity switch with a mechanical one makes it usable. But one must consider the original reason for choosing a proximity switch – was it because of an explosion-proof area? If it is in an explosion-proof area and the proximity switch is replaced with a mechanical contact switch, then the junction box must be made explosion-proof as well.
This involves converting the NAMUR signal to a dry contact, which is possible; simply invert it at the safety barrier