I'm looking for an out of the box power monitor plug that specifically doesn't have a switch/relay to turn it off. I'm thinking of monitoring something like my sump pump so I want to be 100% sure something won't turn it off.
Something that can handle large loads would be good too.
Z-Wave is preferred but ZigBee would work.
You can use an aeotec HEM5 and monitor it the breaker. That said I don't think anyone makes a z-wave or zigbee outlet that doesn't switch. What would be the point? Now you can use one and simply leave it on and not include it in any automations that would turn it off or on and simply read the attributes for the power from it.
I use a Zooz ZEN15 to power monitor my sump pump. It is built for that kind of load, and you can disable manual control at the plug. I thought there was also one to disable remote control, but not seeing that. I have a timed routine in RM that turns it on every 10 minutes whether it needs it or not.
Mother Nature is giving my sump pump monitoring a nice workout this afternoon:
I like how you have all hose details on your dash. How did you set up the cycles and last time ran, and interval? Great information to monitor.
Check out How use a zooz zen15 and not too many reports? - #3 by HAL9000
You could also have a Basic Rule, Simple automation or RM that turns it on automatically when it is turned off. I have a few of those for similar situations…
Shelly wifi EM meter can do this job.
I know you said you prefer z-wave but the driver I have for my Tuya Metering Plug [BETA] Tuya Zigbee Metering Plug has an "Always On" preference setting which is meant to prevent it being turned off