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Sombreuil_mongrel
Suggest a Relay please

I need to be able to turn on a 120v 1/3 hp electric motor remotely via a low voltage reed switch. Is there an easy to connect relay unit with its own 12v power supply built in? And the coil would need to be continuous duty, as the reed switch is on/off not momentary contact.
Tell me what I need to buy. Thanks.
Casey

guy48065
Re: Suggest a Relay please

How about a remote-operated shop-vac relay? A small box plugs into a receptacle, the motor plugs into it & you activate it with a keyfob remote. Pretty cheap at ~$50 I think.

Sombreuil_mongrel
Re: Suggest a Relay please

The reed switch is already installed. Fob not an appropriate application. But thanks for your response.
Casey

Mastercarpentry
Re: Suggest a Relay please
Sombreuil_mongrel wrote:

I need to be able to turn on a 120v 1/3 hp electric motor remotely via a low voltage reed switch. Is there an easy to connect relay unit with its own 12v power supply built in? And the coil would need to be continuous duty, as the reed switch is on/off not momentary contact.
Tell me what I need to buy. Thanks.
Casey

Casey, your best bet would be to check with either a local electric motor rebuilder or a commercial electrical supply house. Lacking those a commercial HVAC outfit may be able to help- some of their stuff uses relays rated for this level. Before you set off, you need to know what amperage the reed switch is rated for so they can match that to the pull-down coil. If that rating is really low you may need an intermediate relay as well as the main one, or to go with a higher rated reed switch. If you know those ratings, some of the surplus electronics dealers 0nline might have something usable and cheap. If you get really stuck, message me and I'll try to dig a source up for you.

Phil

Sombreuil_mongrel
Re: Suggest a Relay please

That's a good idea; there is a motor shop in the next big town over. And the reed switch is rated at 20A so I think it's fine. I could also ask the previous owner what relay he used...
Casey

canuk
Re: Suggest a Relay please

Casey -- do you always want the motor to run whenever the reed switch is closed ?
If so , with a 20 amp reed switch and 1/3 hp motor that reed switch should be good enough by itself. Just wire the reed switch in series with hot for the motor.

Now , if you want to control the motor on/off when the reed switch is closed -- a 20 amp switch can be wired in series upstream of the reed switch.

Sombreuil_mongrel
Re: Suggest a Relay please
canuk wrote:

Casey -- do you always want the motor to run whenever the reed switch is closed ?
If so , with a 20 amp reed switch and 1/3 hp motor that reed switch should be good enough by itself. Just wire the reed switch in series with hot for the motor.

Now , if you want to control the motor on/off when the reed switch is closed -- a 20 amp switch can be wired in series upstream of the reed switch.

Hi,
Yes that would work, but I do not want to run a 120v wire inside the organ console. I'm wiring a blower motor for a chamber organ.
Casey

canuk
Re: Suggest a Relay please

If that's the case then use a 6 - or 12 volt ac/dc adaptor ( 300 ma is plenty ) and pick up an Omron LY1 relay. They come in 6 or 12 volt dc coil and switch 120 volt 10 amp.

I've used the Omron relays in industrial controls and they are pretty reliable and reasonably priced -- around $12.
You may even have a wall-wort kicking around from an old electronic device -- answering machine , cordless phone , etc.

canuk
Re: Suggest a Relay please

You probably know how to wire everything , but , just in case.

Sombreuil_mongrel
Re: Suggest a Relay please

Thanks everybody. I'm now idiot-proofed! Onward.
Casey

Fencepost
Re: Suggest a Relay please

An all-in-one solution would be a Honeywell RA889A switching relay. Contains internal power supply transformer. These are typically used to permit the use of a low-voltage thermostat with a line-voltage heating appliance.

http://www.pexsupply.com/Honeywell-RA889A1001-120V-60-Hz-Switching-Relay-with-SPDT-switching

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