Answer / welcome4ujd

dry contact is that the contacts are floating. One example
is the COM, NC and NO contacts of the relays. If no voltage
is connected to them, it is called dry contacts.
Volt-free and dry contact mean the same thing. If a control
system supplier offers a dry contact for you to read as a
status bit, then he is offering to close a contact (relay
or contact output) that is nothing more that a stand-alone
set of contacts with no voltage, current, or anything else
impressed across the contact set. It becomes the user's
responsibility to determine how to sense that contact
closure. Usually you do this by putting a voltage on one
side and sensing the voltage on a return line from the
other side of the contact when it closes. Once you apply
voltage to the contacts, it becomes a wet contact.
You "wet" the contact with a sensible voltage level.
.

Answer / daher

same as answer #1

Answer / abhijeet

Dry Contact means contact before connecting voltage signals....while as Wet means connecting instrument in Circuit...!!!!!

Answer / greg gertsch

It has been my understanding; Dry contacts when open do not
transfer any voltage or currant to the load side.
wet contacts have voltage on the load side but no currant
flow. Such as when a varistor is used as a bridge allowing
line voltage to cross over to the load side which minimizes
the arcing on contact points

Answer / einstainn

when you dips the contact into liquids then we call them wet
contact..hahaha

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