Overloaded extension cable or not?

[marconi]

I discovered while visiting an elderly neighbour she was using a 2 socket 2m long extension lead wired with 1mm2 PVC 3 core (- both a Duraplug double socket and 13 amp and 10 amp fused plug) to supply her ironing board in her lean to extension on which she had plugged a 2.2kW steam press and 2.4kW steam iron. She had been using this arrangement for a year. No visible (internal or external) problems to any of the electrical components. Extension supplied and wired by a friend who was a retired electrician. Even a label near plug to only fit a 10 amp fuse. Extension originally used for lady's sewing machine and a lamp but then change of use for the ironing and pressing arrangement now.

Thoughts invited on whether to continue with this arrangement.

 

[Marvo]

Are you sure the extension lead is 1mm and not 1.5 which is more common?

If the leads aren't getting warm to the touch during use then I'd say they're fine. Are they supplied by a circuit with RCD and MCB protection innthe CU? You could always test at the end of the lead and calculate the disconnection time in the case of a fault.

 

[amlu]

if you feel worried rewire it with some heavy duty 1.5 h07 flex and get some tea and biscuits

 

[Lucien Nunes]

Those power ratings only apply while the elements are on. As both the press and iron will be thermostatically controlled, their loading will cycle between 2.2/2.4 kW and zero so there is a bit of diversity. An iron on medium setting might only be on half the time, in which case the average heating of the cable will be halved (although not quartered as it would be with an element of half the power switched on all the time). As the thermal time constant of the cable is probably similar to that of the iron, it probably doesn't exceed its rated temperature despite the theoretical possibility of overload.


That said, I hate undersized extension cables. 1.25 minimum, preferably 1.5 for a 13A. Why bother with anything less?

 

[marconi]

Those power ratings only apply while the elements are on. As both the press and iron will be thermostatically controlled, their loading will cycle between 2.2/2.4 kW and zero so there is a bit of diversity. An iron on medium setting might only be on half the time, in which case the average heating of the cable will be halved (although not quartered as it would be with an element of half the power switched on all the time). As the thermal time constant of the cable is probably similar to that of the iron, it probably doesn't exceed its rated temperature despite the theoretical possibility of overload.


That said, I hate undersized extension cables. 1.25 minimum, preferably 1.5 for a 13A. Why bother with anything less?

Thank you to you all for your replies. As it plays on my mind I will do the right thing and replace his arrangement for her press and iron. I like margins in cables - it is IsquaredR after all that produces the ohmic heating in them. I will buy some 1.5mm2 and provide two single socket extensions one for the press and one for the iron and band them together for neatness between her ironing board and the double socket she uses. I will look at her consumer unit at the same time. I suspect it is a fusebox. Some work hopefully in the offing for a local sparks I know who will do a good job at a good price and the necessary inspection and testing (and any required remedials).

As well as making good tea and cake she is a real character to talk with.

 

[Deleted member 72666]

Good luck with trying to get 1.5mm² into a duraplug! It'll be a real struggle for sure! As it wont only be tea and biscuits you'll be having, you'll still be there at tea-time also! I would use either 1.25mm² in your setup or 1.5mm² in an MK 'toughplug'.

 

[davesparks]

Good luck with trying to get 1.5mm² into a duraplug! It'll be a real struggle for sure! As it wont only be tea and biscuits you'll be having, you'll still be there at tea-time also! I would use either 1.25mm² in your setup or 1.5mm² in an MK 'toughplug'.

Duraplug 13A plugs are designed to accept up to 2.5

 

[telectrix]

wire the extension lead in MICC. :behead:

 

[Deleted member 72666]

Duraplug 13A plugs are designed to accept up to 2.5

Really! Definitely not the ones I've come across which you'd struggle to get 1.5's in. Have you a part number or link to these please.

 

[davesparks]

Really! Definitely not the ones I've come across which you'd struggle to get 1.5's in. Have you a part number or link to these please.

I take it back, I was wrong. Either my memory is failing or the spec has changed but the Duraplug 13A and 15A are only specced for 1.5
The older ones could take 2.5, unless it's the permaplug I'm thinking of. We get through so many of the damned things I think I fit them half asleep now anyway.

 

[Deleted member 72666]

I take it back, I was wrong. Either my memory is failing or the spec has changed but the Duraplug 13A and 15A are only specced for 1.5
The older ones could take 2.5, unless it's the permaplug I'm thinking of. We get through so many of the damned things I think I fit them half asleep now anyway.

We only use these now: Tough Plugs the 'pvc top' ones and in my opinion they are the best plug-tops on the market!

 

[davesparks]

We only use these now: Tough Plugs the 'pvc top' ones and in my opinion they are the best plug-tops on the market!

Fair enough, but there isn't a 15A version and they aren't black rubber so it'll never be seen in theatre!

 

[Lucien Nunes]

Although the 13A Duraplug is designed for 1.5 and it fits nicely, they will take 2.5. It's tight but the result is sound if you are careful. We went over to Permaplug for our 15A but then started having quality control issues, mainly bad terminal screw threads, so returned to Duraplug.

 

[davesparks]

Although the 13A Duraplug is designed for 1.5 and it fits nicely, they will take 2.5. It's tight but the result is sound if you are careful. We went over to Permaplug for our 15A but then started having quality control issues, mainly bad terminal screw threads, so returned to Duraplug.

I hate 15A permaplug, they're all plasticky and horrible, almost as bad as Walther commando plugs Duraplug is much better.

 

[Dave OCD]

All these posts about extension leads, why not put a proper double socket in for the old lady close to the appliances and wired in 2.5 ?

 

[davesparks]

If there's nothing wrong with it why not leave it as it is?