RELAY THAT ACTIVATES ITS SWITCH WHEN POWER IS REMOVED?

[nasaiya]

IS THERE SUCH THING AS A RELAY THAT CONNECTS ITS SWITCH WHEN NO POWER IS PRESENT AND DISCONNECTS ITS SWITCH WHEN THERE IS 120V PRESENT? I AM TRYING TO MAKE A CIRCUIT THAT DETECTS IF AN AC LINE IS HOT. IF THERE ARE ANY BETTER WAYS TO DO THIS PLEASE LET ME KNOW!!

 

[RalphChristie]

Undervoltage relay

or

use the Normaly-Close contact of any relay. If your relay sees 120V the N.C. contact will open and disconnects the load.

 

[maged541946]

Hi,
Most relays come with a NO and NC set(s) of contacts.

NC is Normally closed i.e. when no power is applied to coil, the set(s) are closed (shorted) when power is applied they are open

NO is Normalty open, when no power they are open and when power is applied they are closed (shorted)

Get one that has a coil rating of 110 VAC

Actually each set is a reed connects pins 1 and 3, when coil is powered, this reed is pulled to connect 1 and 2, when power is off , it is released and returna with a spring to its original 1 and 3 position

Maged A. Mohamed

http://magedm.freeyellow.com

http://www.magedsoft.com

 

[nasaiya]

thankx alot thats exactly what i needed, now i just need to find a cheap supplier uughh

 

[controldude]

http://www.releco.com

cheap little plastic relays, around $10 if you're able to get one or try

http://www.digikey.com.

-dude

 

[controldude]

sorry, try going from here with a request for quote:

http://www.turck-usa.com/products/relays/index.htm

i'd select the 120 Vac relay, it has either NO or NC contacts, as pretty much all single pole relays do.

-dude