First impression: these plugs are small. Is there any room for current measuring?
After reading some articles about the NEO COOLCAM NAS WR01W I started to believe more that these plugs actually couldn’t measure current. On all the available images online, none off them where showing a current sense resistor. So there was only one option left: Opening up the plug
Opening up the plug
Opening up the plug is quite easy. One screw to open the plug and two screws to get the circuit out of the casing. The last two screws you can see in the two holes where the socket goes. After unscrewing those two, you’ll need to bend the metal earth strip. After that you can wiggle carefully the circuit out of the case. I highlighted the carefully, because there is a antenna wire connected and I didn’t want to re-solder that cable, yeah I’m kinda lazy 🙂
The circuit
After opening up the plug and looking to the plug I new it for sure: No voltage/current/power measuring 🙁
I saw that the neutral goes via the passthrough circuit to the other circuit. The life goes via a relay on the passthrough circuit. I made some comments on one of the images trying to explain how I think it works.
The life and neutral goes via the passthrough to the other circuit. On this same circuit, there is an AC/DC converter. I didn’t measure the voltage but I’m assuming that it’s about 5~12V. This DC goes via the upper two pins off the passthrough. On this passthrough is besides the relay, also a buck-converter. This is most likely for lowering the voltage to 3.3V for the ESP8266EX.
Findings
When looking to the passthrough print and the size and thickness of the high voltage part on all the circuits, I do think that chasing 10A MAX through it is quite risky. I wanted to use them for power measuring for my washing machine and dryer, yet I don’t know if that’ll be safe with peaks of 9 Amps.
A waste of money?
For me this is a waste of money, as I don’t need switches. If I do need switches, these are hard to flash. You’ll need to open them in order to flash, while other cheaper versions like the Sonoff’s are easier to flash. These plugs are going on eBay to at least get a little bit of money back 😀
Peter de V
You can flash the smart plug without opening.
Just use a Raspberry (with WiFi) and run the Tuya-Convert script. Connect a other device to the wifi and flash your smart plug. I flashed 15 smart plugs succesfully 🙂 See this link: http://www.thesmarthomehookup.com/tuya-convert-walk-through-february-2019/
Marcel
Hi Peter,
Yeah I heard/read something about that. Yet the time I was doing this, this was (for me though)the best way. For sure I would do it different next time 🙂
These plugs couldn’t measure current, and that was a bummer for me. I already sold them quickly.
Cheers,
Marcel