Devices plugged into BS1363 Socket Oulet

[Midwest]

Came across this today, a device, which was plugged into a socket outlet, experience a short circuit of plug in power supply. Pics below.



I suspect the device was damaged by a heavy item being placed up against it over a period of time, causing the low voltage wiring being exposed & twisted, causing a short. So that can be rectified.

I'm questioning whether the device should have some additional fusing, like a BS1363 plug (in this incident it caused the 32A RCBO to trip), and in the last pic the authenticity of the CE mark. It does seem to be like the CE I've found on-line.

Its the fusing that perplexes me; no different to a phone charger etc I suppose. Did cause a large flash & bang.

 

[johnduffell]

I suppose it didn't need a fuse according to the wiring regulations as there's no flex but it wasn't built to handle the mechanical stress in the environment.
Not sure if that should have been covered by pat testing, if it was vulnerable for many years I'd expect it to be picked up. The new socket heights can be more risky for bed collisions

 

[DPG]

The main part of 'PAT' for that item would have been regular inspection. This may have picked up the damage, but it depends when it occurred and when it was inspected.

 

[Midwest]

Ok so no local fusing required. Its an establishment I'm new to. I've had my concerns about how various items of furniture have been positioned, compared to what I believe is their original design position.. This is an example of the consequences.

 

[Midwest]

The main part of 'PAT' for that item would have been regular inspection. This may have picked up the damage, but it depends when it occurred and when it was inspected.

This particular room has only been used for the last few weeks, and the items added more recently.

The issue I think is the way an item of furniture has been positioned, in relation to socket outlets and items plugged in. Think just posting here has made me think, and I'll discuss with my boss.

 

[DPG]

It's often a problem with bulky plug-in type stuff.

Has anyone seen the heaters that JML are advertising at the minute? An element and a fan in a great big box that plugs straight into a 13A socket. They're going to break a lot of sockets them things

 

[Spoon]

and in the last pic the authenticity of the CE mark. It does seem to be like the CE I've found on-line.

Looks like a CE Mark to me.

Warning: don’t get confused between the CE Mark and the China Export Mark - YBW - https://www.ybw.com/vhf-marine-radio-guide/warning-dont-get-confused-between-the-ce-mark-and-the-china-export-mark-4607

 

[netblindpaul]

The Chinese Export mark is an urban myth. Both the EU & Chinese authorities have stated such.
The best explanation is that the so called Chinese Export mark is a bodged attempt at applying the CE mark.

 

[Lucien Nunes]

A plug-in SMPSU (wall wart) should not fail, let alone go bang, just because the output cable is shorted or damaged; it should shut down or go into burst mode to protect itself. It should not trip your ring final even if there is an internal fault on the primary side, as some type of fault protection should be present in the AC input circuitry. It might not be immediately recognisable as a fuse, as it might be in the form of a non-flammable fusible resistor or SMD component, but there should be something.

Your unit appears to have had a flashover at the mains input filter. Without seeing the other side of the PCB it's hard to tell exactly what's where, but my hunch is that the PCB is of poor design, a component failure has occurred and the ensuing arc has flashed across to the unprotected side, eating away the tracks in the process. This might indicate that the supply is non-compliant with the relevant standards e.g. IEC 61204-7:2006.

I handle, test and inspect quite a lot of SMPSUs that are sent to work under adverse conditions. I need them to be robust, safe and exceptionally reliable, and there is a remarkable variation in these qualities from brand to brand. I have been known to pay upwards of £300 for a decent, large power brick; not surprisingly these are in a different league technically to the cheap ones, which are themselves in a different league to the non-compliant knock-offs.

 

[Shoei]

A plug-in SMPSU (wall wart) should not fail, let alone go bang, just because the output cable is shorted or damaged; it should shut down or go into burst mode to protect itself. It should not trip your ring final even if there is an internal fault on the primary side, as some type of fault protection should be present in the AC input circuitry. It might not be immediately recognisable as a fuse, as it might be in the form of a non-flammable fusible resistor or SMD component, but there should be something...

Agree, it's safe to say that failing like that (tripping a 32A breaker!!!) the PSU doesn't conform to any safety standard. The company claims compliance to EN60950 which requires overcurrent protection in primary circuits, the materials to be fire resistant to UL94-V1 or better and for the enclosure to contain any fallout from a failure.

I wouldn't trust that supply in any application and would look around for a replacement made by someone else. In theory it's a trading standards issue, if they took an interest the importer of that kit would have some awkward questions to answer.

 

[Midwest]

That was kinda my thinking, responses from @Lucien Nunes & @Shoei.

Just to be precise, in case the pic is not clear, its the 230V input cables that have shorted out together, not the secondary side.

 

[Shoei]

That was kinda my thinking, responses from @Lucien Nunes & @Shoei.

Just to be precise, in case the pic is not clear, its the 230V input cables that have shorted out together, not the secondary side.

Best guess is the bridge rectifier on the mains input has gone short, as Lucien says there will have been a fuse of some sort, that supply should only take about 60mA from the mains even running at maximum power, so the fuse should have been small, even allowing for some surge capability and having to work down to 100VAC. The fuse or maybe PCB tracks have failed with a big flash and the resulting plasma has toasted everything in range, including the socket, only saved by the 32A breaker. Sort of thing you see in the black museums at the test houses.
We've all seen this sort of stuff and put it down to experience but it may be worth a chat with trading standards, if they are out there in any volume a product recall could be on the cards.

 

[telectrix]

maybe the cat has pi$$ed on it.

 

[Midwest]

If you look at the first pic, those two red wires connect straight onto the live & neutral terminals of the ‘plug’ pins (underneath the white plastic plate).

Its these two red wires(230V) that have got twisted and shorted out.

 

[DPG]

Probably a combination of a not so good quality power supply, and the physical damage. Fact of life these days.