Last fall, I posted about using an input on my ZEN17 Relay to monitor our sump pump while away for the winter. The ZEN17 was way overkill for the job and needed to go back to controlling landscape lighting when spring rolled around.
Enter the ZEN57 800LR 240v XS Relay. This new product fit the bill and turned out to be way simpler to implement!
Using a Nodehawk 0-30 amp Normally Open Current Sensing Switch and the ZEN57, I prototyped this application as shown, below. The current sensing switch–which can be adjusted to close its dry contact relay when the current flowing through the input transformer rises above a preset value–connects directly to the switch input pigtails of the ZEN57. Two turns of 14 AWG wire in series with the load outlet are looped through the transformer of the current sensing relay.
Power from the 120v AC power line is applied directly to the L and N terminals of the ZEN57–no additional power supply is needed. Note: the output of the ZEN57 is not used in this case: it’s only function is to report the state of the relay in the current transformer. Follow the instructions in the ZEN57 240V XS Relay Advanced Settings article to configure the input as an on/off report (dry contact switch/sensor), rather than the default function.
On the Z-Box hub, I set up a notification when the pump runs. If it runs often, you might choose to just check from time to time. As an extra precaution, I have a ZSE42 800LR XS Water Leak Sensor next to the sump hole to warn if the pump fails to do its job.
Next up is to package this mess in a more appropriate housing and attach it to the wall above the sump pump. 
The ZEN57 800LR 240v XS Relay and its cousin, the ZEN58 800LR LV XS Relay (which runs on a 9-40 volt power supply) are excellent additions to the Zooz product line.
Highly recommended!
That is a great find. Thank you. ]