PAT testing query

[JACKC]

Hope you can settle this arguement. Boss came into work today with qty 4, 30m extension leads all on a standard plug. I told him they need PAT testing before use and as they are over 15m's for 1.5mm cable they need the plugs cutting off and replacing with rcd plugs. **** off he said, if they weren't ok then they wouldn't make them that length. Explained about ELI and rcd protection but he still won't budge on it. Says if they weren't safe to use at that length they wouldn't make them. Why do they make them that length if it is against the max length stated in the Code of Practise, can't think of a good enough one to convince him. Joe public can buy and use them but they are not good enough according to the C.o P.
Any reason to persuade him will be most helpful. Thanks in advance.

 

[ericmark]

Because of course you can use them at that length if the premises comply with 17th Edition.

I got quite upset when my wife bought a lawn mover and the guy told her she also needed an earth leakage adaptor to make it safe. At 10ma maybe but since all circuits in the house already have 30ma protection the item was about as much use as a chocolate fire guard.

This applies with many items we buy. I can use a consumer unit in an office without any Part P paperwork and to try to prevent shops selling consumer units would be daft. Same with boat and caravan.

Some countries Hong Kong for example do require the shop keeper to view licence or passport before selling items like amateur radio equipment but in this country I have not seen these restrictions.

The problem I had with extension leads is too easy to move so in the workshop they may not need any RCD but in the Offices they may. The same goes for a load of other items. Using a radio with a 2.5amp connector for lead set in an Office is OK. But on the factory floor where water may be present that type of lead set would not be any good.

As a result the place where they were used and tested was always recorded.

I took the attitude that if there was a mixture of sockets protected and unprotected by RCD's we had to ensure RCD plugs were fitted to long extension leads. But there is nothing to stop people from daisy chaining the extension leads.

 

[RF Lighting]

I don't see the issue.

The max permitted Zs for your average socket circuit is 1.16Ω

The earth conductor on your extention will have a resistance of 12.10mΩ/m

This equals 363mΩ for a 30M lead.

That gives you a Zs of 1.52Ω at the end of the extention.

Lets add half an ohm for mucky contacts on the plugtop and socket.

That gives you a Zs of 2.02Ω at your extention.

A 13A BS1362 fuse will give you 0.4 seconds disconnection at a Zs of over 2.60Ω.

Seems ok to me.

 

[JACKC]

Thanks for the replies. Why is it then that the Code of Practise puts these maximum lengths for extension leads in it? I can see that the ELI for sockets would be well under for some circuits, thanks for that. We do not have ant rcd protected sockets at work so I am right in insisting on rcd as we use grinders etc on the end of these leads.
thanks again.

 

[RF Lighting]

I can't think of anything forcing you to RCD protect the leads, but it is obviously a good idea.

Is this a place of work? Should power tools not be running on 110V?

 

[ericmark]

EAW act is vague in the way it is worded and it refers to causing danger etc rather than an exact figure.
Much is the way you word things as to if the boss will pay out for things to be improved.
Farms and construction sites are the only areas where the BS7671 requires 110 volt equipment but where there is a high risk then it is normal to include workshops etc in the 110 volt system.
One thing is anything with heath and safety must be written down. I have given my boss a note before not telling of some problem and said when giving it to him what you do is up to you but I am instructed I must give you notice in writting.
But you must be careful not to over do it. Although a boss is unlikely to say I am getting rid of you because of health and safety issues you keep bringing up they may get rid of you for some minor thing which normally they would turn a blind eye to.

My point is to say to boss I don't want them to ever come into my workshop or I will have to put a PAT test fail cert on them is different to saying you shouldn't use them they are not within regulations.

So maybe you could ask the boss for a plug in RCD adaptor for use with the leads when not plugged into an RCD socket?

I haven't got the new PAT test book but a 13 amp fuse is good for an ELI of 3.83 ohm and a 32A B type MCB is 1.44 ohm so the resistance of the leads should be under 2.19 ohms and a 1.5mm lead has resistance of 0.029 ohms per meter which gives 75 meters. So I would just say nothing as although the old book says 12 meters for 1.25mm, 15 meters for 1.5mm and 25 meters for 2.5mm it is not really upsetting the boss over it.

However I would not record any PAT testing and if he questions it just say I know they will fail as too long so thought it better not to test.

Not worth risking your job over.

 

[JACKC]

Thanks for the replies, it's a car workshop so Boss not worried about 110v system. Will suggest rcd's and then fit my own if not done.
Thanks again

 

[Spark123]

You'll struggle to PAT test with an RCD type plug on anything - they are usually active devices and don't like IR tested.

 

[ericmark]

In all the motor vehicle workshops I have worked in all power tools either pneumatic or 110 volt centre tapped.
See this pdf document where is does suggest 110 volt should be used.
See page 3 but considering this is a HSE document I would say there is no enforcement on use of 110 volt.

Maybe asking the question why the limit on extension leads is well below the point where ELI will become a problem on the IET forum would get better result this forum is intended for DIY!

 

[Grizzly]

You'll struggle to PAT test with an RCD type plug on anything - they are usually active devices and don't like IR tested.

Then you'd do a Protective Conductor Current test instead (if your PAT device can do such a test). See IEE CoP (3rd ed.) 15.6 (p76)

 

[JohnD]

**** off he said, if they weren't ok then they wouldn't make them that length.

They wouldn't make cigarettes if they killed you, right?

 

[Spark123]

You'll struggle to PAT test with an RCD type plug on anything - they are usually active devices and don't like IR tested.

Then you'd do a Protective Conductor Current test instead (if your PAT device can do such a test). See IEE CoP (3rd ed.) 15.6 (p76)

Or as we do, just don't use them!

 

[Grizzly]

Or as we do, just don't use them!

Yes, that is another valid solution