Almost burnt the house down

Yo,
Another post in short succession, but I feel it may be of interest. It’s possibly a wake up call for any high power device, but this just happened to happen to my Twizy. Basically the plug melted, which fortunately didn’t turn catastrophic. However, things are 100% better now and I can sleep at night. Sorry for pulling people away from this forum via a link, but I hope the message is the same.http://www.daswolfgang.com/twizy-epic-fail/

As you say it looks like a poor connection on the live side.

Possibly caused by moisture inside the plug or vibration loosening the screw?

I worry about things like this, which is why I have a good quality MK socket to plug my Twizy into and a heat detection alarm fitted in the garage.

I also don’t like the idea of charging the Twizy whilst not at home.

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Note that many of the smart connectors like the one you are pointing to in your weblink, have poor internal relays that are not capable of switching 8A without risking a fire later on.

We have had a couple of fires in garages in Sweden when people have been charging using timers and smart relays…

The first issue here is that is is a cheap extension lead with poor sockets.
The next is the Plug on the Twizy cable does not look like an original one. There could be a loose connection in there. The Plugs were often exchanged as the original ones are a lot bigger than standard 3pin 13amp plugs and do not always fit in to some sockets.

Timers and Switching devices are fine provided you use ones that are rated at a high enough rating. Here in the UK there are timers that operate Immersion heaters. These are designed to switch more than 13 amp and run for hours at a time.

They do fail but usually due to timer part if mechanical rather than the relay.

The one I have is rated at 16amps

Off toppic:
Yes car fires are quite common in Sweden nowadays … Perhaps these are not directly due to the electricity but they occur every few times a week.

https://www.gp.se/nyheter/göteborg/bilbrand-i-frölunda-i-natt-1.982908

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It does not help that it is rated 16A. Every time it turns off with high currents active on it (or on with high currents, which is not relevant in this case) you have a spark. This spark will cause oxidation at the connectors if they are not of very good quality (expensive metals). I rarely see high quality material in these small relays.

When I built my own charge-box for my other car, I used a contactor instead. It is controlled by an ESP8266 via an SSR-relay to get optical isolation (the contactor is to the right, the 12V transformer to the left and the web-controlled computer module is in the middle with an OLED display). The box becomes a bit clumpsier, but it will not cause a fire at least. The entire chargeBox was built for less than £100 where the majority was the cost of the TYPE-1 charge cable (the rest costed about £40).

In the normal case your solution will probably last for quite long, but as you already had one fire I just thought that you should be a bit more careful. I have had two elctricity fires in my house, where one was started by a poor relay construction (not my own). Luckily none of them spread.