Use a Shelly 1PM with 240v Pool Pump switch?

Hi all, hope this isn’t a dumb question but I’m not finding a lot of info when searching. I have a pool pump zwave switch (https://www.amazon.com/gp/product/B00YTCZZF0/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1). The zwave has stopped working and I believe it’s the device. I like the box with a manual on/off, it also has an option to be either “ON”, “OFF” or “ZWAVE”.
I’ve had good luck with the wifi Shelly 1PM devices. What I wanted to ask is if I could put a Shelly between the breaker box and the Zwave Pump switch. What I’m hoping to accomplish is to power the Pump switch via the Shelly and avoid the Zwave. I can leave the Pump switch in “ON” mode and let the Shelly be the automation switch. It would also give me power usage stats which would be a bonus.
Am I correct in thinking I can use a Shelly 1PM for this 240v pool pump switch?
Where I’m getting confused is that the pool pump switch has two “LINE” wires going in and 2 “LOAD” wires going to the pool pump. I don’t see 2 LINE wire places on the Shelly, or do I only need to wire 1 LINE wire for this to work? Appreciate any insights or advice. Don’t want to use a device that’s not safe but I think this is doable. I know it’s an odd use case but I want to keep the existing switch box in place and just control the power to it via the Shelly. Thanks!

According to the specs you linked your switch is a double throw single pole switch - this means it can switch two lines - both live/phase and neutral - switching both provides compete isolation for the load when it the switch is off.

The Shelly is a single pole switch - it only switches the live/phase conductor meaning the neutral will still be connected unless you turn off the zwave device before doing any work on the pool pump. The Shelly would go in the live/phase conductor going to the existing switch. You’d still have the double pole isolation provided by turning the zwave box off.

BUT your existing switch is rated at 40A, the Shelly 15A - what current does your pump draw? If it is anywhere near 15A then Shelly will not do the job - it’s a tiny box and you don’t want it getting warm.

You could replace the existing zwave switch with a double pole contactor controlled from a shelly but you won’t get power monitoring.

Not qualified to give advice just my thoughts

Good luck

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No that Shelly isn’t good for that load. If you’re using 240v and have that switch then you’re in North America and that means two phase power. You need something that can do two pole switching as @steve_jo mentions.

In addition it’s a pump. Meaning a heavy duty electric motor which means inductive load. It will pull a pretty severe startup current which will eat a smart device for lunch If it’s not rated for it.

The GE you have is probably even borderline but at least it’s designed to handle that. I’d stick with what you have - just new. If you do t want the GE unfortunately most of the switches in this class that are controllable with a Northamerica power setup will be ZWave. I think Zooz has one that may work as well.

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Thank you both for your replies, just the information I needed. I think I’ll look into this wifi pool pump switch instead : https://www.amazon.com/DEWENWILS-Outdoor-Wireless-Controller-Compatible/dp/B07PP2KNNH/ref=cm_cr_arp_d_product_top?ie=UTF8

Appreciate the fast responses!!

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