A potential free contact usually means the switch portion of a relay. Potential free contacts, or dry contact as they are also called,
neither supply nor sync current but switch the sync/source current you supply. A potential free contact does not mean however that is does
not have a minimum and maximum. Be sure you know its specification.
It just means what it says, it's a contact that doesn't provide any potential. This is exactly what the standard manual switch or relay
contact provides as opposed to a digital output that usually provides 24V when active and 0V when not active. The consequence of this is
that you can use any signal with a potential free contact, (as long as it is within the allowed range) and you can put several of them in
series or parallel, which would not be possible or meaningfull with ordinary digital outputs.
Potential free means that there is no potential at the two terminals. In other words, the unitdoes not generate any potential weather positive or negative at the two terminals.
I believe that youcan use any device meeting such
definitiin a potential free context.
Anand
