Author Topic: Can I wire dumb and smart switches in parallel?  (Read 390 times)

Offline cc4005

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Can I wire dumb and smart switches in parallel?
« on: April 16, 2018, 10:00:34 am »
Subject line is the question. I don't know enough about how a z-wave switch works to know whether it cares if there's voltage on the load side when the z-wave switch is off since it's not a true air gap...

My specific case is a remote bathroom fan serving 2 adjacent bathrooms. I want to keep a non-zwave, electronic countdown switch in one room and automate the other bathroom switch using an Aeotec micro switch at the fan triggered by a dumb toggle in the bathroom. Smart timer by Vera and dumb timer continues to do its thing--completely independent of one another. Humidity sensor triggering might come later.

Thanks.

Offline cc4005

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Re: Can I wire dumb and smart switches in parallel?
« Reply #1 on: May 07, 2018, 11:04:59 am »
In case anyone else ever needs to know...after 3 days the parallel configuration is working as intended. No immediate ill-effects on the Aeotec micro. I'll report back if I observe any longer-term problems that could be attributable to the wiring configuration.

Offline Tillsy

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Re: Can I wire dumb and smart switches in parallel?
« Reply #2 on: May 07, 2018, 07:43:21 pm »
In theory it should be fine given ultimately the Aeotec would likely have a relay simply shorting the voltage across the two pins, so wiring a switch in parallel is simply providing a secondary path for that same current.  But, without studying a schematic or taking the device apart, it would be a risk not knowing exactly what you might be potentially injecting voltage in to.

Personally I've done almost exactly what you are seeking with my outdoor lights, but with Z-Wave association instead.  My front lights are wired to a dual switch, and in the process a light switch for manual control.  I then have a regular outdoor 240V movement sensor (in your case substitute this with your timer) that, rather than wire directly to the lights or shorting the output on the dual switch, I have wired to the secondary unused input on a nearby dimmer.  I then have a Z-Wave association from that secondary input to the front lights.  Thus achieving exactly what you have done, but via software rather than electrical load.  Also means that, if done via a scene rather than Z-Wave association, there could be decisions made on exactly how/when that external trigger works.