Answer / karthik

A dry contact is a potential free contact

A dry contact is a contact that does not provide voltage.
For instance, the push-to-talk switch of a microphone,
which just closes a circuit without providing voltage.

A wet contact is a contact that will provide voltage when
closed, like the switch on the wall that activates the 110
VAC outlet to turn a lamp on in a room.

Answer / shri gokul

Potential free contact means there is no volatge between
contact terminals. when coil of energized, it will get
closed / opened depends on contact position NO/NC

Answer / sk

Potential free contacts (also called "dry contacts") are
simply contacts which are physically operated with the main
device, but not electrically connected to it. For example a
motor contactor often has auxiliary contacts that are
operated by the main coil and open and close at the same
time as the main contacts but are not used for control of
the motor starter. If they are connected to an outside
circuit to indicate the status of the starter without being
powered by the motor supply they would be considered
potential free contacts.
These type also called Signal-Contacts.

Read more:
http://wiki.answers.com/Q/What_is_potntial_and_potential_free_contact#ixzz1d6LFHY9N

Answer / dharmveer

A dry contact is a contact that does not provide voltage.
For instance, the push-to-talk switch of a microphone,
which just closes a circuit without providing voltage.

A wet contact is a contact that will provide voltage when
closed, like the switch on the wall that activates the 110
VAC outlet to turn a lamp on in a room.

Answer / naushad ali

A contact not used by owner is a potential free contact to the user.Think about a MCC and an Instrument panel.

Answer / narenkumar1985

DRY CONTACT IS A POTENTIAL FREE CONTACT(0V), USED FOR
CLOSING THE CIRCUIT.
WET CONTACT IS POTENTIAL CONTACT(+24V).

How to calibration of vibration probe

1 Answers   Mina Al Ahmadi Refinery,

Explain about 4 wire instrument concept & tell about its wiring fron sensor in Field to PLC panel.Explain with an example?

3 Answers   IOCL,

please any body have most important data for study for saudi aramco test of instrument QC thanks email shahnaveedullah@gmail.com

0 Answers  

when the instrument tapping on pipe line is located below and transmitter is located above the tapping point for liquid service transmitter, what should we do, is there any additional drain valve is required??

0 Answers  

what is the difference between laminor flow and turbulant flow

2 Answers   Invensys,

why gray colour is choosing to all instrument panel.why not choosing other colour?

1 Answers   Reliance,

I need to know steps to Calibration Valve Guard......

0 Answers  

what is the working principal of pribe

0 Answers  

What is loop1 and loop2 in MTS LT?

0 Answers  

What different types of problems do occur while doing the loop checking? and please explain in detail or mail me at kadam.aniket143@gmail.com

1 Answers   Operational Energy Group, Process Control Technologies,

why we are not using the turbine flow meter in the steam service?

0 Answers   Jaypee,

What is feed factor and its Importance in cement industry? How we can solve feed factor?.

0 Answers