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muskyman
27-02-2009, 05:02 AM
I've been told a dry contact is a contact with no voltage present.If no voltage, why have a contact? Dumb question maybe, but I dont understand it.:off topic:

Tesla
27-02-2009, 06:38 AM
Hi muskyman
NOrmally used for a status input to a controller such as an air pressure switch to confirm that a fan is running. Once the status is true or on then the controller would allow a chilled water valve to open for cooling or an electric duct heater for heating - you could imagine what might happen if the heater came on and there was no air flow because a belt snaped (fire). Or on a contactor there is usually an auxillary contact which can be used as a status to controller to indicate an overload trip or fault. We need something to switch off or on for a status, the contact switches. Most controllers would blow up if you put 240v to an input, some can take 24v but then you might have to pay for an extra 24v transformer.

nike123
27-02-2009, 07:36 AM
I've been told a dry contact is a contact with no voltage present.If no voltage, why have a contact? Dumb question maybe, but I dont understand it.:off topic:

[/URL][url]http://tinyurl.com/cgcj3u (http://en.wikipedia.org/wiki/Dry_contact)

muskyman
01-03-2009, 01:07 AM
Nike123, you're an asswhole

Quality
01-03-2009, 06:26 PM
I've been told a dry contact is a contact with no voltage present.If no voltage, why have a contact? Dumb question maybe, but I dont understand it.:off topic:

A no volt or volt free contact is one that can be operated or operate a signal or switch in another circuit which is electricaly independant from each other. I think the terminoligy dry & volt free may be a different term which we use in UK for a different contact and you don`t over the pond. This may or may not help just keep posting to get what you want;)

muskyman
02-03-2009, 04:07 AM
Thanks for the info Tesla and Quality.I thought this website was for asking questions ,but nike123 seems to think otherwise.

nike123
02-03-2009, 07:10 AM
Thanks for the info Tesla and Quality.I thought this website was for asking questions ,but nike123 seems to think otherwise.


I think that some research at Google (or any other search engine) and searching this forum previous posts, to see if some answers at subject is already easily available, and already addressed, is minimal effort before asking questions, and I am sure that most of members here are thinking the same.

Since answer to your question is in many articles returned by Google search engine I taught that my link is also educative.

Sorry, if you did not learn anything from link because it was mentioned to do so.

But, you could always add me to your ignore list (http://www.refrigeration-engineer.com/forums/faq.php?faq=vb3_board_usage#faq_vb3_troublesome_users) or report my posts to administrators with that little exclamation sign at header of my posts.

nh3wizard
02-03-2009, 05:52 PM
Nike123, you're an asswhole

I believe he was just pointing out that Google is available for use by all, and usually will answer your question if you take the time to search.:confused: