I have a pair of athom v1 smart plugs running tasmota. One being used to monitor a fridge-freezer’s power draw. The first one blew a capacitor and a few months later so it seems has the second one. Though the evidence for the failure is not as obvious as with the first (which blew the cap case clean off).
I managed to prise them open and replace the cap on one, which is back in use. The second plug, I damaged the enclosure beyond re-use trying to open it.
This fridge draws about 0-75W with a short burst, of about 250W every 24 hours, where it defrosts.
Now I want some replacements… Question is, are these smart plugs intended to be used with continuously running medium sized appliances?
I’ve got several of these - also Tasmota. I’ve had one on the fridge for about a year with no problems.
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No. I did a few tests with known loads and they seemed accurate.
If you don’t have any reason to switch the load better directly use a non-contact way of measuring the AC power/energy. A pzem004t-v3 is very precise (no calibration needed) and doesn’t need to have a relay energized to work. 
The BL0937 is a better HLW8012 (which is the worst/cheapest power meter chip usually found in products). A CSE7766 is already more accurate and AFAIK a pzem004t-v3 is about one of the higher accuracy AC power/energy meters avaialble in esphome/tasmota. When it’s about the bang for bucks category I would definitly declare it the the winner 
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I agree, non contact is better but on a fridge it would mean stripping back the outer insulation of the flex to access either line or neutral.
There is a new shelly product that doesn’t have a relay, can’t remember if it’s a plug or a module.
Not necessary, just build a plug/socket with a pzem in-line and don’t mess with your fridge 
Not thought of that, good idea
Many thanks for that suggestion. I was not aware of those and will definitely take a look.
I don’t require ability to switch the load. I have a basic ESP8266 clamp meter on my electricity meter right now and did consider doing the same for the fridge. But the compactness and convenience of the passthru style smart plugs appealed to me, that is if they don’t go pop!
