Why are simple relays so much of a problem?

My project was simple, a sump pump float. The small float has a tiny reed switch in it. I needed a Zigbee Input device (inexpensive) single channel.. Way to hard to find. The closest thing is a relay which has terminals for a local switch. Perfect, I really didn't need a relay to turn anything on but the switch terminals would report back to my Hubitat..
Not so simple, the first one was a Sonoff ZBmini-L Zigbee 3.0 compatible, Hubitat paired with it but I tried everything to get it to work, no-go so I returned it.
Next one was a SparkleIOT Mini smart switch, SAME thing.. BUT this one worked like a charm with my Smarthings HUB very simple. My sump pump project is done for now.
My next purchase MHCozyZG1CH Relay NO-GO same thing as the 1st one.
WHY are these such a problem for HUBITAT??
Do I really need 2 different hubs I my life? I hope someone can shed some light on this one before I return it (MHCozyZG1CH Relay) or Id like to just find a compatible input sensor that will allow just a contact closure to send a message to Hubitat..
Hubitat -0
Smarthings -1
Thanks for listening :slight_smile:

I've only used the Zooz relays, so I can't comment on the others you tried, but for a simple zigbee switch, use a contact sensor that also has an additional set of contacts to attach a switch. Either the switch or a magnet will fire off a message to Hubitat.

I'd love to find one with the capability of screw terminal to attach wires.
My next project will be to use old alarm system hard wired switches in my daughters house for Hubitat inputs.
I ripped out the old alarm system and have a bunch of wires hanging down. She doesn't want another alarm system but I think I could talk her into a nice voice alerting her to doors and motion sensors that are already installed.
Let me know if you see any such sensors.

Look at this one:

Shelly Wi-Fi Switch


For use as a dry contact sensor ZigBee device, some people are using the screws on this water leak sensor to attach wires to.

1 Like

I haven't bought one in while and they have upgraded them but the Ecolink Z-Wave Door and Window sensors (DWZWAVE2.5-ECO) have (or had) screw terminals - I wire alarm reed switches to these for my gates that are outdoors.

1 Like

I have the 4-channel version. After pairing, I set it to a Generic ZigBee Multi endpoint switch. Has worked great for me for a year.

These look good and several reviews stated they are using them with Hubitat.. Although one of the ones I tried were the same brand only a slightly different model. The price is right though.
I wish it was a simple 'plug and play'.


I'm also a big fan of the Zooz ZEN16/ZEN17, but if i absolutely needed something zigbee, I'd look at the Sinope MC3100ZB multi controller. It's not cheap at $80, but if the application warrants, it is probably a rock solid device.

If its anything like the original ZBMINI, these aren't really meant for any type of input signal. They are primarily an output relay with an option for local switch control. All you'll ever see in Hubitat is the state of the output relay. It doesn't track or report the state of the input, it just knows enough to toggle the output when the input switch is toggled. This is a limitation of the device, not hubitat.

For my project, just knowing when the relay closes due to the local switch is all I need. Currently the Hubitat pairs with the device but I don't see any kind of response.
I don't believe the current one 'MHCOZY' paired properly. The flashing LED doesn't stop after the Hubitat supposedly paired..
There must be some custom code needed for these things (3 different ones so far). Getting frustrated because one of them worked great on Smarthings.. :frowning: I'm hoping someone can come up with some code. Thanks for your input.

First off you should be aware of this warning about the MHCozy Relay from @aaiyar:

But these devices do with natively with HE as I have used both the single and dual relay models:

I believe the Sonoff ZB Mini should be working? I think I have seen other people talk about it before.

I used two different cheap relays from Ali in my basement and they work great. Now I am not using the switch inputs, only the outputs, but I see no reason why the inputs would not work. Need recommendations for unfinished basement lighting - #18 by jtp10181

Also I have seen a lot of people use the Ecolink contact sensor since it has external contact terminals. I cannot seem to find a picture of it for proof but if you search the forums you will see people talking about it. Possibly nice thing about that option is it has batteries.

The problem with the ZBMINI is that it doesn't track the input state. If the input switches back and forth too quickly, the output relay and input switch can get "out of sync." This is likely a deal breaker for any kind of float switch.

Again, the device works just fine with HE. It's just not meant for tracking the input switch state.

1 Like

all the mhcozy relays are supported, we have tested the 1, 2 and 4 channel versions using the multi endpoint switch driver


any suggestions/recommendations for a z-wave equivalent? (ie simple input device)

Ecolink Contact sensor has been recommended for inputs, and you can convert it to being main powered with a battery adaptor. It has built in terminals to connect an external input.

Also, the ZEN17 has dual inputs that can be monitored.

I'll second the recommendation for the ZEN17. There are others, but none that have the same combination of features at a price that is just too hard to pass up.

Mike, thanks for the reply, I did not get anywhere with it and I tried everything. Definitely not "plug and play". I had all kinds of Smarthings sensors that paired and worked flawlessly with Hubitat. The 3 different kinds of relays I tried didn't work with Hubitat. As I said before the project I was working on I had to deploy a Smarthings hub because Hubitat failed on all 3 relays. It's too bad because there is not many more low cost relays. I'm only looking for one I can use for inputs and don't even need a relay..

I also had no issues pairing one of the MHCOZY zigbee 4-channel relays to my hub.

I saw this on another thread and thought you may find it useful. Another user is using these devices as simple input modules.