Automation & Rules

Been looking at purchasing a Dual Relay Switch Module Control for motor automation. I have not found if a rule can be created on to turn only 1 relay on at a time. Reason being is i want this controller to allow a high and low speed motor control. Is this possible? Or are other motor controls available that I have not come across. Thanks!

Reading the Q & A on Amazon reveals this:

Can I control the 2 loads separately/independently?

A: Yes. They are both controlled separately of each other. If you turn on one, the other remains off and vice versa.

Sounds like this reports as two separate switches (it does in a Vera system apparently) so there’s no reason it won’t work the same way on ADC.

Great thing about Amazon…you can return just about anything for just about any reason.

J.P Thanks for the reply. I did come across that Q&A on Amazon. My worry is that if this switch is used as a 2 speed motor control both switches could possibly be turned on at the same time, in my case that would be high and low speed on the same fan. Maybe ADC will come out with “if” statements that can use on z wave devices.

Ah I see. I haven’t seen anything that would allow you to program switches with an if/then logic with regards to the status of a different switch. It would be nice if they did though, as I’d like to program some lights to come on when locks are opened for example but only if it’s dark out. They have sunrise/sunset logic and I’m using that already for exterior illumination but I can’t integrate that parameter into other rules, say for interior lights, at this time.

I guess I have to ask what the harm is if both commands are sent at once, at least from an equipment damage standpoint. If there’s no exposure there I’d probably try it personally.

What kind of motor are you trying to control?

J.P., If i did accidentally have the switches come on it would be kinda like taking your car out and pressing the brake and the gas at the same time, it will work but not for long.

Ryan,I was hoping to install this setup on a 2 speed exhaust fan. Motor is 1/2 hp. I am not sure on the amperage without looking at the motor plate but it is under 10A.

LOL I got ya…doesn’t sound like an ideal situation :slight_smile:

Could you accomplish this safely with some clever wiring? I haven’t worked with that device but instead of wiring them as 2 independent switches, what if you wired the relays in series? The first relay would be the overall on/off switch for both motors. The second relay would switch power between the 2 motors guaranteeing that only 1 of them can get power at a time.

+120VAC — Relay 1 Common
Relay 1 NO — Relay 2 Common
Relay 2 NC — Motor 1
Relay 2 NO — Motor 2

Again, disclaimer, I have not tried this with that device. Try it at your own risk. But if they’re just simple relays it seems like it might work.

Which compatible control panel do you have?

Since I’m not familiar with that Z-Wave dual relay device, another way I know you could make it work would be to use 2 Z-Wave lamp modules and an AC relay that has both a NO and NC contact. Lamp module 1 would turn the fan on and off. Lamp module 2 would be used to power the coil on the relay and switch power between NO and NC.

Lamp Module 1 Z-Wave Output - Relay Common
Relay NC - Motor 1
Relay NO - Motor 2
Lamp Module 2 Z-Wave Output - Relay Power Input

You could name the first lamp module something like Fan On/Off and the second lamp module something like Fan High/Low.

If you can’t find an AC powered relay you can use a DC powered relay and a DC power supply together.

That is definitely a wiring solution I did not think of with the NC and NO relays. I will do some more thinking on this and will let you know if I give it a try. The only major problem is little time to tinker with projects such as this during the peak of summer.

I will be using this setup with the Qolsys alarm panel. Does anyone know if ADC will come out with “if/then” statements to use with z-wave devices?

If/Then logic based on switch status is likely a very tough addition. Due to Lutron patents, covered in previous topics, light switches cannot “richly convey their status” to controllers, unless they are Lutron. Essentially this amounts to controllers needing to constantly poll the status of the light switches in order to know them. Not all controllers do this. 2GIG and Qolsys do not. does not pull status of light switches (all switches would fall under this command class category), so If/Then programming would have to be limited to a local controller until such time they can work around the patent.

In the example of If (locks), then (lights) given above, that may be possible since lock status is relayed.