Monday 18 November 2013

Dangeorus IEC Power Cords

Recently, a sample of an IEC power cord was sent to me by Gerald Ruane of Ashdale Electrical Testing. This was following a Linkedin discussion started by Patrick Maher of PAT's Testing Swindon. Below is a report on this highly dangerous lead.
 
I tested this lead on a PAT Tester and it failed Earth Continuity - it was off the scale. I checked Earth Continuity on aMilli-ohm meter and it was reading around 0.15 ohms. It was only when I took a close look at the plug that I realised the reason for this. Have a close look at the photograph below.

The Earth pin is insulated. This means that in a standard wall socket, there is NO connection to the earth of the wiring installation. 

The result is that someone using this on a Class 1 appliance will not have any Earth protection at all, making the use of this lead highly dangerous.

Digging round on the internet, I came across the following links which readers of this blog may find interesting.

http://bournemouth-pat.co.uk/page8/files/94c055721c2f2ac3995a4008df1e6ccd-0.html
Brief note regarding insulated earth pins.

http://www.bs1363.org.uk
This is a very interesting feature on counterfeit plugs which includes examples of insulation on Earth pin, inadequate cable rating and plugs with no fuses. Well worth a read.

The image below shows the marking on the plug more clearly.

In summary, this has been a very useful exercise in identifying an IEC power lead that is highly dangerous. Please keep a watch out for this when you are carrying out PAT Testing.

6 comments:

  1. I have been asked to PAT a coffee maker that has no exposed metal and no Class II marking. How do I test the earth bond? I don't want to leave out the earth test, as the water tank could become live in a fault.

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  2. Hi Mick, the text here explains Class 1 Plastic appliances and how to test them. http://www.patinfo.co.uk/pat-testing/examples.html

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  3. I understand what you're saying and thank you. Does it still apply to water-filled appliances? Would I be right to think that a loose live lead will be isolated from the water? Why aren't they marked as Class 2, which in effect they are?

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  4. Hi Mick, can you access the element inside the coffee maker? Is the lead to it a 3-core lead? It is most likely to be Class I with an Earth but also covered fully in plastic so that no one can access the metal bits inside (even if they became Live due to a fault).

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  5. The element cannot be gotten to. The plug is moulded, so I don't know if there's an earth. There's no Class II mark on the rating label.

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  6. In which case Class 1 Plastic is best way to proceed.

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