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relay to control appliance power on/off

relay to control appliance power on/off

relay to control appliance power on/off

(OP)
Hi forum! I'm looking where to find a relay too switch on/off a house appliance using 220V and rather low current (for example a light or a small machine) by using a 5V control voltage with max. 30 mA current. Is there a relay with such values? Can I use a microcontroller circuit outputing these values (5V vs. 0V) to use in an application like this??
Can you point me into a relay model i can use for this??
thanks in advance for any answer and sorry for the newbie question (new in electronics, just trying hard...)
Ivan

RE: relay to control appliance power on/off

Go to McMaster-Carr, Digikey, Allied Electronics, Newark Electronics, Omron, etc., and look around.  You should be able to find something.

RE: relay to control appliance power on/off

Try Allen-Bradley or Cutler Hammer they should have what you need

RE: relay to control appliance power on/off

hi..
check the omron catalogue..
look for miniature relay..i believe they have 5 volts working coil...commonly used in output section of OMRON PLC's....good current capacity ...we used it in powering up relays in heat seal and heat tunnel machines...and cheap too...the only thing is you are going to need a relay socket unless you want to solder it straight to the board which i don't recommned..visit...

www.omron.com

dydt

RE: relay to control appliance power on/off

hi

use ULN2003 to drive relay from a digital circuit like a microcontroller or even you can use a single transistor.

you can see ULN2003's data sheet on www.ti.com

RE: relay to control appliance power on/off

One thing to keep in mind when selecting a relay is to find one with a HP rating or VA rating(make and break), depending on the mfg. It sounds like this may be a motor of some sort, so a standard relay would not work without the appropriate ratings. A transistor configured as a switch is a good way to drive the coil of these relays unless your microcontroller can source the current required by the relay coil. I believe it is difficult to find a 5V coil relay with current requirements less than 30mA to switch the load you are talking about. You may find it in a 12 volt coil.

RE: relay to control appliance power on/off

Use a Solid State Relay (SSR). SSRs are readily available to switch up to 480 volts at 25 amps with a 3-32 VDC input.  The input current should be about 15 mA at 5 volts. Try Omron or P&B.  I have used these many times to switch power with an electronic controller.  

RE: relay to control appliance power on/off

you could also use a 5vdc to 24vdc Solid state relay to switch 24vdc to a 24vdc 3 pole contactor. I imagine that a SSR capable of swithinch 480 v 3 phase with a 5v input signal would come with a hefty price tag.

Best regards, PLCSAVVY

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