Watch out for those 13Amp fire hazards

[RogerS]

AKA 13 amp plugs and sockets.

Was busily routing out with my 110v DW625 when it started to cut out intermittently with all the hallmarks of a failing speed control circuit. So switched off and could smell burning. That got stronger and stronger. Looked over my shoulder to see smoke pouring out of the factory fitted plug where it was inserted into the power strip.

Pulled the plug out and left the neutral pin behind.



Glad it happened while I was present.

Note to self: Never leave a 13 plug powered up and covered with anything.

 

[marcros]

a useful warning Roger. Thanks.

 

[johnphilip]

should this not be 240 volts or is my brain not working today

 

[Phil Pascoe]

13A 110v ? It doesn't look like a 110v plug to me.

 

[johnphilip]

13A 110v ? It doesn't look like a 110v plug to me.

thanks i thought i was cracking up , if its a yankey ver 110 volt could it not be 15 amps :?:

 

[RogerS]

No.o.o. 110v DeWalt and a 240 > 110v transformer !! Standard UK sitework requirement.

 

[Phil Pascoe]

So the plug was on the transformer, not the router?

 

[tekno.mage]

What was the rating of the power strip? I had a similar incident last year. I had a 300W uplighter plugged in via a 4-way power strip, which was then plugged into a single socket 13Amp extension lead which ran along a wall to the nearest 13 amp outlet. My partner then plugged a 2KW electric fan heater into the 4 way to test it out. After about 15 mins, my uplighter went out and the fan heater stopped working and a nasty smell arrived, which we initially thought was the fan heater. It wasn't. It was the plug from the 4 way which had happily melted all over the extension socket. Odd - 2.3kw on a 13amp rated 4 way - not ideal, but should have been able to take it for 15 minutes. Further investigation revealed that the 4 way was actually only rated at 10Amps (marked in tiny, tiny, writing on the base) - but had a 13 amp fuse in it's plug. Rubbish Chinese electrics :-( I thought it was a legal requirement for multiway extension leads to be rated at 13Amps?

 

[RogerS]

The load on the power strip would be the onload of the DW625 + losses in the transformer. Nothing to write home about. But a good reminder to bin the 4-way strip as well.

There is much to be said for having a master on/off switch for all the power in the workshop that you can turn off at night + a dedicated circuit for keeping power going to, say, a vacuum pump.

 

[MMUK]

A multi-way extension lead can be rated at whatever the manufacturer decides. Normally speaking the cassette type (like JO-JO) are rated at 10A. You'll also find that they only have 1.0mm cable and not 1.5mm.

The reason for a 13A fuse is that 10A fuses aren't widely available in domestic circles.

Nothing to do with it being Chinese, you should have checked the rating of the extension lead first.

 

[tekno.mage]

A multi-way extension lead can be rated at whatever the manufacturer decides.

In which case surely the rating should be clearly marked on the extension block! Not in tiny writing badly molded in to the back of the unit and almost impossible to read.

Yes, I should have checked the unit, but a 4 way block that is not rated at 13 amps is not something I would ever expect to see.

 

[rileytoolworks]

The load on the power strip would be the onload of the DW625 + losses in the transformer. Nothing to write home about. But a good reminder to bin the 4-way strip as well.

There is much to be said for having a master on/off switch for all the power in the workshop that you can turn off at night + a dedicated circuit for keeping power going to, say, a vacuum pump.

This is exactly what I do. As i leave the workshop, the master switch on the fuseboard goes off.

Gives me peace of mind and stops any nasty surprises in the morning (and when the leccy bill comes!).

All the best.
Adam.

 

[Paul Hannaby]

Even if the melted extension had a 10A fuse (which are commonly available) it may still have melted with the same load. Most wire fuses are only guaranteed to blow when they are subjected to double their rating. i.e. a 10A fuse may not blow until it was subjected to over 20A. In a fault situation, the fault current is almost always much greater than that so the fuse blows almost immediately but under mild overload, the fuse may not blow, causing the overheating.

Another one to watch out for is the roll up extension leads. When rolled up their rating is often significantly reduced, sometimes as low as 4A.

 

[tekno.mage]

True enough Paul - I was just appalled to find I owned a 4 way extension lead that not only was not rated at 13Amps, but was not clearly marked as such. There was no obvious difference between it and many other 4 way extensions I own. The cable was around 2 meters long, was visibly as thick as other 13Amp extensions I own, and it wasn't the type where the cable can be rolled up (a bit short for that). I do have some lightweight 5A extensions I have made up myself in the past (for use with lighting only), but they only have a single socket and are clearly marked with their rating at both ends.

 

[Phil Pascoe]

Paul said another one to watch for was rolled up extension leads - other than loss of capacity, THEY CATCH FIRE! I worked for years in a hotel, and I've lost count of the number of melted one I threw away because people had used irons on them for too long.