Safety of using an extension cable for a washing machine and/or tumble drier

Yes. beware extension cords when coiled. I have had them melt.

Tumble dryer is the worts case. Lots of heat for long periods. Check its power rating against the extension

Its all about cooling

And print up little labels to stick on them

Where's that riund tuit!

Also take care when using both WM and dryer together. eg you might transfer a load to the dryer and immediately start a new wash in the washer. That means the both washer and dryer will be heating at the same time, which might be too much for the extension. Better to stagger them, eg once the WM has filled and heated up (and done any prewash) then you're safe to turn on the dryer as it's then only running the drum motor and pump (both fairly minor loads), assuming the rinse cycle is with cold water.

If you have a plugin power meter you can observe when it takes power during the cycle, and after when it's safe to run them together.

Theo

Don't forget that you'll be running the extension off a ring main which might have other loads plugged into it at different sockets. Just watch that the overall load doesn't build up so much that the MCB on that ring main trips. It can be easily done when you're focussed on what is being plugged into an unusual extension rather than the whole ring main.

Yes, I did say "are we safe to run the washing machine and tumble drier not simultaneously)" for that reason ;-)

Good idea about using a power meter to monitor power consumption in the different phases. Drier probably uses fairly constant high power through cycle but washing machine will use a lot of power for heating and then less for motor as it agitates in hot water.

At first, I thought that washer, drier, dishwasher and oven were all on the same ring main, but it turns out that dishwasher and oven are on a separate spur to feed just one double socket for those.

I'm always amazed that 30 A ring main MCBs don't trip more often because it is easy to have too many high-power devices plugged into the same ring main, which is fine until the day when several happen to be used at the same time...

The previous owners wrote some very cryptic wording on the tiny labels that fit within the plastic housing alongside each MCB. "Helpful" things like "Storage Heaters" when AFAIK the house has always been heated by gas boiler, and "Misc sockets" (yes, but which ones?).

Our house was extended in the 1990s and the extension has a separate consumer unit. I've no idea how it connects to the meter and company fuse because there doesn't seem to be a heavy-duty cable coming up from underground with one input (from meter) and two outputs (to extension's CU and the one for the original part of the house which is on the other side of the wall to the meter cupboard.

How ever it has been done, powerline network connections (Ethernet over mains wiring) is non-existent between two sockets which are a few feet apart but on different CUs. Mind you, comms between sockets on different rings in the *same* CU is pretty ropy as well. I'd toyed with the idea of using powerline to get Ethernet around our L-shaped house, before abandoning that and going for several mesh network nodes to provide coverage. Running Cat 7 cable around the house failed the SWMBO test for unsightliness: easy to run the cables through the loft (the older part of the house is a bungalow) but a pain running the cables up walls and through plasterboard ceilings without being unsightly.

I'll ask for a gross of round tuits for next year's Christmas present.

When I was a teenager and my parents had just moved to a new house, I drew a floor plan with all the sockets and wall/ceiling lights marked, and annotated each with a code (eg "L1", "L2" etc for lighting circuits, "R1", "R2" for the ring mains), and marked each fuse or MCB with that code. Such youthful dedication to the task of turning off each circuit in turn and finding what no longer worked ;-) Overtaken by events when the old fuse box was replaced by a new one a few years ago.

The use of “coiled” extensions is a frequent topic in Motorhome / caravan circles.

Generally, the modern sites have 16A supplies on the hook up posts, a tad under 3700W at 230V.

It isn’t unusual for modern motorhomes / caravans to have electric heating and electric water heaters, microwaves, some people use electric kettles, air fryers, toasters, ….. that is before you include low power things like TVs, fridges, lights, chargers, ……and we must remember hair dryers!

Seeing photos of melted or worse coiled up extensions is not unusual. Standard advice on handover to beginners is to uncoil the cable fully and lay it out safely but you still see coil up leads on sites.

Of course, some people use gas heating, don’t use kettles etc, or have older systems which tend to be lower powered.

Our latest MH has a circuit which not only measures the current being drawn but allows you to set a limit for sites with lower rated supplies. Our previous ones didn’t.

Then there are inverters. The number of questions re inverters to run devices which should never really be run from inverter with a tiny battery is staggering. …….

Never underestimate inrush current of switched-mode power supplies (eg laptop charger/PSU) when they are first turned on.

I have a 12V to 240V inverter which I keep in the car. I once tried to charge my laptop from it as I was driving. As soon as I connected the PSU *without the laptop connected to it* to the inverter which was already powered from the running engine, it blew the 16 A 12 V fuse - so there was about 200 W even on no (DC) load.

I'm always surprised at the crack and fizzle when I plug the laptop PSU into normal 240 V mains.

Plug it into the 13 amp socket on the cooker connector (if there is one) and only use when outside times that heavy duty cooking is happening.

My wife discovered that the ring main covers more of the house than we realised: when she came to dry her hair using the socket in the en-suite bathroom (yes, a *long* way from any water or earthed taps!) those sockets weren't working either.

That reminded me that there is a TV distribution amplifier for sockets in the bedrooms, in the roof space just above the bathroom, and when I investigated, that had no power either, and its socket has a feed that runs down the wall towards the bathroom.

I unplugged that amp and I'm now able to turn the ring main back on without tripping the RCD. Either the amp is the guilty party or else water that had got into the wiring somewhere has now dried out.

Some day I'll try plugging the amp back in (or try it in a different ring main) and see if it was the culprit.

I feel that it is going to be a long involved job trying to identify the source of the problem.

Why couldn't the circuit have tripped while we were at home, when I could quickly and easily have rigged up an extension cable for those freezers? Sod's law that it happened when we couldn't do anything about it.

The galling thing is that we could see that something was up, even when we were aboard the cruise liner (*) in the Canaries. One of our new security cameras had gone offline. Some of our power-monitoring sockets had become unresponsive. Both of those symptoms *could* have been caused by one of the wifi network nodes losing connection with "mother ship" - or they could have been caused by a partial power cut (not a total one or else all the other smart plugs would have stopped responding and my Raspberry Pi would have stopped updating our weather station website.

(*) Iona, the ship that was delayed setting off from Southampton because of those shipping containers of bananas etc that fell off a ship in the Solent. We missed going to Maderia because of the 20-hour delay leaving Southampton :-(