Noticed something odd with my Zooz switch

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I noticed some odd behavior when testing a Zooz Zen73 switch.

I connected the switch to mains power on my test bench (it has already been associated with my Z-wave network) in order to test it a bit as i had shocked myself when connecting a light to it when the switch was supposedly off. I started probing it with my multimeter when I noticed something really weird.

When there is NO LOAD on the switch, as in the load wire is not connected to a load, the switch appears to send 120VAC out the load wire when I meter it against neutral and the switch is switched OFF! When the switch is in the ON position, I get 70-71VAC between the load wire and neutral.

When I attach a load to the switch (I've now connected a lightbulb to the load) it behaves normally, ie switch ON powers the bulb, switch OFF turns the bulb off.

However, when the switch is connected to mains power, AND load is connected BUT the switch is OFF (ie no light from the bulb), you hear a relay click on and off when you attach or detach the load wire from the bulb even when the bulb is off and the switch is also off.....

WHAT THE HECK IS GOING ON?! Can anybody explain this really weird behavior.

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2

There is probably an X cap between the line and load terminals to reduce arcing when contacts close, or an EMI filter across a triac if one is used.
These methods do conduct a small amount of current, even when the switching device (relay or triac) is "OFF".
The current to a load is low enough to not energize the load, but you are much more sensitive to these small currents.
Best way to test these devices is to wire a small load, like a light bulb, to the load terminals.