I’m looking for a mechanical ZWave “switch” that physically stays in it’s “state” when power is lost or the device fails.
If folks recall from the X10 days, a X10 outlet was actually a mechanical switch inside that would flip on or off with a solenoid. There was no relay. And it consumes the same power in either state. Only uses the coils during a state change.
The only device claiming this behavior is a WiDom Universal Relay Switch but I’m not sure it does what I want and not easy to find in the USA.
The reason I want this is, I want it for a Furnace and I have it On for 6 months and Off for 6 months. But occasionally would like to turn it off or on remotely.
I don’t like the idea of an Coil needing to be “Active” to Keep it ON for 6 month or OFF for 6 months.
Coils will and can fail. And it would be a real pain if it failed. It seems all ZWave switches have failure reports and I can deal with that. But I want it to fail in the state it was last left.
One way to test if a device is a mechanical switch is, if you turn it on, you’ll hear a Click for almost any device that isn’t solid state or a dimmer. But if you remove power (while “On”), do you hear another click (coil releasing the relay contact)? What I’m looking for, it would NOT click when you remove power. Nor would it click again to restore state when power is restored (because it mechanically stayed in the correct state).
I highly suspect such devices exist, but the descriptions are vague.
There are “Active” latching (or BiStable) relays that use a feedback circuit to hold the relay in it’s state (without a signal). These are often used when you want a Momentary signal to turn it On or Off. But still requires an active coil to hold that state. But that is not what I’m looking for, and I suspect the WiDom unit might be that type of device. But it claims it’s the only “Latching” Relay.
I’ve looked at the GE 40 Amp Relay 12726, NuTone NFS20Z, Remotec Dry Contact Relay, Aeotec Nano Switch , Quibino Switch (last 2 look similar to WiDom switch) and I cannot tell from the descriptions what these actually do inside.