63amp extension lead

[iamelectric]

got a job to install a 63amp supply 3 phase commando socket , for a lighting show for an opening night , it was a metre from the D.B so i wired it in 16mm SY cable, i have now been asked to supply am extension cable for it , one male plug one female plug , about 25m long , i was thinking of using 10mm SY for it as its more manageable , but 10mm comes in at 61 amps ccc , is this ok as its an extension?

 

[iamelectric]

a commando plug does not have a fuse in it , i have seen many extensions and machines plugged into 32amp circuits without being fused down

 

[44ALLAN]

a commando plug does not have a fuse in it , i have seen many extensions and machines plugged into 32amp circuits without being fused down

The cable will be rated above 32 amp though and the machine will have its own protection

 

[Guitarist]

a commando plug does not have a fuse in it , i have seen many extensions and machines plugged into 32amp circuits without being fused down

You seem to be missing the basics of matching cables with their protective devices.

 

[thebigcheese]

It's an art

It might be an art but I can't see how on a trailing plug and socket it can be done. Do you use special glands to bond the steel to earth?

 

[DPG]

well its like plugin a machine in that only has a 1.5 cable into a 32amp circuit

Would you use a 5A extension cable to power a 10A appliance, fed from a standard ringmain? Daz

 

[Toby Kuhnert]

You seem to be missing the basics of matching cables with their protective devices.

As Guitarist says, this is basics....

 

[44ALLAN]

It might be an art but I can't see how on a trailing plug and socket it can be done. Do you use special glands to bond the steel to earth?

1st you untangle all the braiding.
Then you separate enough braiding to fit into the earth terminal with the integral earth core.
Twist said braiding together and sleeve with green and yellow.
Then cut the remaining braiding to about an inch in length and fold back over the cable end and apply heat shrink to hold in position and tidy the end up.
This will be awkward in a 13amp plug I'd agree

Or you could just do what most people do and cut all the braiding off and wrap some tape around it lol.

I don't recommend sy cable for trailing cables that are being moved continuously btw.

 

[varilite]

Go to a tv lighting hire company and hire what you need already made up and complient for outdoor use

 

[Darkwood]

Firstly ..may i ask why you already used SY does the set-up and environment warrant the need for it and also i assume the correct glands have been used and the sheath is fully earthed but not used as the earth.

Never!!! use SY for extensions its flexible only to a certain extent it not design for continuous flexing and will see the braiding breaking away from the SY glands and losing its vital earthing of the braid, wholesalers push SY out as a tough use flex but its is often mis-used, its ideal for VSD flexes to motor where screening is needed, its also ideal for control wiring with screening as is its original purpose ... any use where it is layed out across the floor and/or regularly wound up and unwound is an unsuitable situation.

Don't confuse flexed fixed current appliances with an extension lead - if the extension is been plugged into a 63amp socket outlet then it has to be rated for 63amp taking into account its length ....who's to say it won't be utilised for an alternative use.

If the lighting rig has a max fixed load rating then the flex to its 63amp plug only needs to be large enough for the max load that the lighting rig will take - so if say the max load of the rig is 36amps then a suitable flex to it may be rated at 40Amps with a 63amp plug on it.

The OCPD is to protect the installation wiring any equipment plugged into a socket outlet is not covered by the BS7671

 

[Guitarist]

The OCPD is to protect the installation wiring anything plugged into a socket outlet is not covered by the BS7671

Unless it becomes part of the "fixed" wiring

 

[Darkwood]

Unless it becomes part of the "fixed" wiring

I was refering to 430.1 (note 4) as in the OP set up :vanish: i probably should have worded that better by saying any equipment plugged into a socket .....

 

[Guitarist]

I was refering to 430.1 (note 4) as in the OP set up :vanish: i probably should have worded that better by saying any equipment plugged into a socket .....

Sorry Dark, I posted that to the wrong thread....

 

[iamelectric]

thats what i ment by my first post , its not part of the fixed installation , so do the regs cover it