I’ll soon have lots of new toys to play with but for today I’ll talk briefly about some new AliExpress purchases.. here at Bedrock I have typical Spanish rural electricity – there’s a wisdom that they don’t have live and neutral mains wiring here but thanks to some new toys I’m finding out that this is not quite the case. Our mains plugs are not directional (i.e. live/neutral) – but I’ve been doing a spot of learning.
Ever since this article when I received my test screwdriver, I’ve taken an interest in mains polarity and in fact, I’ve always had an issue here with brief power cuts and earth leakage i.e. the standard ELCB in our home occasionally trips with 30ma earth leakage current – usually when I’m not at home (by which I mean I could be out shopping or in another country relying on battery backup – which fails if the power stays off for more than a day – taking my Raspberry Pi home controller down) – but I wondered – how can that be if there is no live and neutral?
Well, the screwdriver sorted out that question but I didn’t want to take down the house electricity just to get to the bottom of this – SO I bought a cheap WIFI device described on AliExpress as “63A TUYA WiFi Smart Earth Leakage Over Under Voltage Protector Relay Device Switch Breaker Energy Power kWh Meter”.
This TAXNELE device (which works with the SMART LIFE APP) replaces the standard 30ma device in our wall and you can program both the current load it takes to turn off the unit and also the earth leakage current required to trigger the device to turn off. But that’s only the beginning. You can have it trigger on mains overvoltage and under voltage too.
More importantly if it does trip, you can have it turn back on up to 3 or more times automatically if the fault clears – handy if no-one is about. After 3 attempts you have to physically press a button to turn it back on (you can turn this feature off). The unit also has remote monitoring via WiFi. Be aware if you see this item that the sheet (optimistically called a manual) that came with the unit originally misleading and out of date – now better but still needs a little work – I’ve included a couple of images of the new version pages at the end.
So, between the test screwdriver and my new resettable earth leakage device, I’ve already learned a lot and hopefully next time we are not here and the power company screw up, my IOT devices will no longer get several on-off cycles in a row – which can cause them to lose their settings and is a common feature/problem on many smart plugs and lamps.
It doesn’t stop there.. I learned that despite what I originally thought, the two power lines here are NOT identical. For a test, If I take a 10w lamp (very low wattage lamps tend not to work for this) and connect one end to earth and the other end to one of the power lines, the earth leakage trips, ground to the other line, generally nothing (however I have one Spanish earth leakage device which will trigger if one lamp wire is earthed and EITHER of the “live” wires is touched by the OTHER lamp wire – so they are NOT the same.
But telling which line is “live” isn’t that easy as there are no L N markings on our Spanish sockets and the wiring colours behind the wall vary from grey + blue to various other colours – I guess whatever the electrician/builder had handy at the time. I decided it was time to rewire any sockets as needed so they are all oriented the same way. I could of course use my test screwdriver to check, but I figured I should do the job properly. Accordingly, I’ve ordered another cheap device so I can simply check by plugging it in – the HaboTest. Looking good – more when it arrives… The device is a HABOTEST HT107 Pro Socket Tester from AliExpress – see pic at the top – also see further down.
Update April 12, 2023 – it turns out that both units should have had backlights – neither of the originals did. I ordered a replacement thinking the only issue was the WiFi on one of my Taxnele units – on the new ones – WIFI works just fine on both and they have backlights on both, too! I’m guesssing a welcome upgrade in the case of the white backlight (which powers down after several seconds).
HABOTEST HT107 Pro Socket Tester
The socket tester arrivived this morning…. and already I’ve noted that most of my sockets seem to be live/neutral reversed – of course as sockets are all reversible I could just plug everything in upside down…
Right now I’m at a bit of a loss as to how the tester knows what the RCD break current is… but the initial reading at least looks useful. More on this as I find out how best to use this device – and thanks to reader Pascual Guevara, I’ve now had confirmation that in spain, blue is considered the norm for neutral as it would be in the UK – and of course green/yellow for earth – but I’m a bit bemused as Pascual has confirmed my thoughts that just about any old colour can be used for live (black, grey, brown are typical – who dreamed up using BLACK for LIVE I wonder). Feedback welcome.