What type of contactor/relay would work?

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jonny1982

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So I have a momentary switch that controls lights that I would like to control with a simple smart switch. So the momentary switch is a regular toggle switch with 3 connections. The one in the middle is constant hot and then it has the top terminal that when the momentary switch is moved up, it momentarily connects the middle and top terminal, and when it is moved down, it momentarily connects the middle and bottom terminal. I want to be able to somehow control this action with a simple on/off smart timer. I was thinking I'd replace the momentary switch with contactors/relays, and then use the on/off smart switch as a control circuit to switch this. I was thinking when the smart switch is pressed on, it would momentarily connect what is the middle and top terminal of the momentary switch, and when it is pressed off, it would momentarily connect what is the middle and bottom terminal of the momentary switch. Does this make sense? Do they make contactors/relays that could do this?

Thanks!
 
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gar

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202020-0845 EDT

jonny1982:

You are describing what sounds like a GE RR relay system where each relay has a set and reset coil. I would describe the control switch as a SPDT with spring return to center.

If this is the case, then you do not want to supply sustained power to either coil or you may burn out the coil.

I have no idea what a smart switch is. How this smart switch works will determine what has to be done.

.
 
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jonny1982

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gar said:
202020-0845 EDT

jonny1982:

You are describing what sounds like a GE RR relay system where each relay has a set and reset coil. I would describe the control switch as a SPDT with spring return to center.

If this is the case, then you do not want to supply sustained power to either coil or you may burn out the coil.

I have no idea what a smart switch is. How this smart switch works will determine what has to be done.

.
Click to expand...

Just forget that it's a smart switch and lets just say it's a regular toggle switch. Basically what I'm looking for is a relay that when the toggle switch is on, it momentarily closes the contactor. Then when that same toggle switch is turned off, it momentarily closes a different contactor.

Or if it is just a contactor with a 120 volt coil and when that coil is energized, it momentarily closes the contactor (the first part of my above question). Then I could just use 2 of those with 2 different switches.

Does that make sense?
 
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jim dungar

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There are several timing issue which need to be clarified, particularly how you are using the words momentarily closed.

If you want the relay to stay on after a momentary closing of the switch, you need a latching device.
If you want the relay contacts to close immediately, with the switch, and then open after a momentary time period you would need a timer with something like a one-shot function.
 
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jonny1982

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jim dungar said:
There are several timing issue which need to be clarified, particularly how you are using the words momentarily closed.

If you want the relay to stay on after a momentary closing of the switch, you need a latching device.
If you want the relay contacts to close immediately, with the switch, and then open after a momentary time period you would need a timer with something like a one-shot function.
Click to expand...

I want to be able to turn on the toggle switch and leave it in the on position, but I would want the contactor to close for any where between 1 and 5 seconds and then open back up automatically.
 
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jim dungar

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jonny1982 said:
I want to be able to turn on the toggle switch and leave it in the on position, but I would want the contactor to close for any where between 1 and 5 seconds and then open back up automatically.
Click to expand...

What you want is commonly found in multi-function timers, or search for just a One-Shot timer or Interval one.
 
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Hv&Lv

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jonny1982 said:
I want to be able to turn on the toggle switch and leave it in the on position, but I would want the contactor to close for any where between 1 and 5 seconds and then open back up automatically.
Click to expand...
Why not just use a momentary pushbutton switch and hold it for five seconds and then release it?
Please, gars post above
 
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jim dungar

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'One-Shot timers' take a maintained contact input and change it into a momentary contact output.

When I googled this term, it took .52 seconds to deliver over 75 million possibilities.
I used to sell the TimeMark and Telemecanique products as well as other brands. Just about everybody offered this function.
 
synchro

synchro

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Chicago, IL
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EE
jonny1982 said:
Just forget that it's a smart switch and lets just say it's a regular toggle switch. Basically what I'm looking for is a relay that when the toggle switch is on, it momentarily closes the contactor. Then when that same toggle switch is turned off, it momentarily closes a different contactor.
Click to expand...

As Jim mentioned, one-shot (aka single-shot) timers are likely to do what you are asking for if I'm understanding that correctly.
You should be able to use the output of a single switch to provide control inputs to both a standard single-shot timer that will trigger when the switch is turned ON, and also to a "single shot falling edge" timer that will trigger when the switch is turned OFF.
Perhaps Macromatic THR-11562 and THR-12262 might meet your needs. The added suffix of -05 has an adjustable timing range of 0.1-10 seconds, but several other ranges are available:

If you drive it with a smart switch then you may have to add a load resistor if the switch has excessive leakage current in the "OFF" state:

Using Solid State Switches with Time Delay Relays

Issue: I have been told not to use solid state input devices such as proximity or photoelectric switches with solid state time delay relays. Why not and what can I do? Solution/Resolution: Ever since the introduction of solid state input devices, designers have had difficulty using them with...
www.macromatic.com www.macromatic.com
I suspect that smart switches which require a neutral connection are likely to have lower OFF-state leakage that those without a neutral connection (because they would not have to rely on a load current for powering up their electronics). But I have no actual data about that.

In your situation I don't think it would matter whether you use a "retriggerable" one-shot or not. Retriggerable means that if the the control input is cycled ON and OFF before the timing interval has ended, then it will extend the duration from that point by a full length timing interval.
 
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gar

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Location
Ann Arbor, Michigan
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EE
202020-2107 EDT

jonny1982:

Really you have not given us enough information.

I have a really simple circuit that may do what you want, but you still have provided inadequate information. This would require a SPDT switch.

The simplest circuit is a SPDT switch with spring return to center, but the circuit I mention above would only require the switch to be a two state mechanical SPDT switch, and would control pulse duration.

.

.
 
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sameguy

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New York
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Master Elec./JW retired
www.serelays.com

SE Relays

SE Relays is a broad line of electro-mechanical, hybrid, solid state relays and sockets used in general purpose and industrial applications.
www.serelays.com
Find one here
 
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