Dry contact output vs Digital output

[ieee_2017]

Hello everybody,

Could you please mention the main difference point/points between the Dry contact o/p and the digital o/p, this term usually shows in the oil industry instruments!

Regards

 

[andre_luis]

Briefly, outputs in dry contact are not electrically energized by any voltage or current source, as would be the case for example the output of a relay.

 

[ieee_2017]

In this case any digital output could be changed to a dry contact by attaching a relay to the digital output! am i right?
Thank you

 

[andre_luis]

There is not a general answer for this question: Digital outputs are often used to carry out fast signals, whereas dry contacts are in general used in power outputs or the ones for which it is required galvanically isolated references.

 

[ieee_2017]

Yes Andre, that is more than enough explaining the difference between digital vs dry contact.... Thank you

 

[Myrobostation]

The relay output gives you dry contact or in other language we can say potential free contact.

So what voltage you are feeding one side of contact that you will get to other side if out put becomes ON. So relay outputs are irrespective of voltage level.


While switched outputs are provided by PLC DO module means if you have selected 24 V DC module then you will gey output of 24 V for all the channels & if you have selected 230V AC then you will get it only.