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Posted By: Tiger Low Voltage Contactor - 06/19/07 04:54 PM
I need a contactor for a special doorbell chime. The chime is 120-volt and the coil on the contactor can be 16 or 24 volt. Anyone know a manufacturer?

Thanks,
Dave
Posted By: JValdes Re: Low Voltage Contactor - 06/19/07 05:18 PM
Yes. Check www.wegelectric.com. Click on E-Catolog. Search part number CW07L310G. Around $25.00.

You can find what you need very easily anywhere. Contactors with 24 VAC coils and contacts for the required current. You can try your local supplier.
Posted By: JCooper Re: Low Voltage Contactor - 06/20/07 12:05 AM
SquareD makes such an animal and a nice little box for it, I used a 30 amp contactor driven with 24VAC. I think the enclosure was more than the contactor, and I got it from Grainger.

Does it have to be a contactor? Can use use a normal cube relay? Most have 10 amp contacts and can be found for 12 or 24 vac/vdc
Posted By: togol Re: Low Voltage Contactor - 06/20/07 01:26 AM
Dave, here is a 12A 8pin http://web4.automationdirect.com/ad...ectro-Mechanical_Octal_Relays/750-2C-24A it even has a test button and LED indicator along with a base it's about 10 bucks
Posted By: Tiger Re: Low Voltage Contactor - 06/20/07 02:40 AM
Thanks everyone. I did a Google search and found that 24V contactors are used in air conditioners. I called my supplier again and he found one for me. He also asked about a relay, but I'm not very familiar with relays.

Dave
Posted By: WESTUPLACE Re: Low Voltage Contactor - 06/20/07 03:53 AM
AC contractors call the contactors with a 24v transformers "fan centers" I ofen use them to control special circuits which require low voltage control. Relays are 12 amp or better. They mount on a 1900 box and seperate low from high. Robert
Posted By: Dave T Re: Low Voltage Contactor - 06/21/07 01:52 AM
Just a suggestion.
Your LV source may not have enough va to energize a LV contactor coil. I would suggest that you incorporate an interposing relay of which its coil, 24vac for example, will function easily with your LV source. When it is energized it would close a contact that would energize the 120v coil which controls the chime.
Also, you wouldn't be plagued with a voltage drop between the bell transformer and a contactor with a LV coil. The coil of a small interposing relay would draw very little current and be controled by a conventional door bell switch. Otherwise, a convertional doorbell switch may not be able to handle the LV current required to pull in and hold a common contactor.
I believe there would be a much less trouble using an interposing relay.
This is intended to think outside the box a bit.
Posted By: gfretwell Re: Low Voltage Contactor - 06/21/07 03:00 AM
You can get some little ice cube relays that handle 5a at 120 and some small metal can relays will do 20a @ 250. What kind of "chime" is this that needs a contactor?

Again I am thinking SSR ;-)
Posted By: JValdes Re: Low Voltage Contactor - 06/22/07 05:48 PM
Dave T, Perfect suggestion.
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