can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW shower

[mikejd]

Hi I have two 6mm csa cables in the loft each going back to a separate 30A mcb in the CU. One is redundant, the other goes to a broken 8.5kW shower. I want to fit a new 9.5kW shower and would like to join both 6mm cables together at a 50A dpst shower switch, then run a short length of 10mm csa cable from the switch to the shower. Can anyone see a problem with doing this. Both 6mm cables are approx same length (12m), there is a RCD in the CU.
Thanks

 

[SPARTYKUS]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Hi I have two 6mm csa cables in the loft each going back to a separate 30A mcb in the CU. One is redundant, the other goes to a broken 8.5kW shower. I want to fit a new 9.5kW shower and would like to join both 6mm cables together at a 50A dpst shower switch, then run a short length of 10mm csa cable from the switch to the shower. Can anyone see a problem with doing this. Both 6mm cables are approx same length (12m), there is a RCD in the CU.
Thanks

what do you think mikejd?

what can you see as the down sides to doing it this way....if any?

 

[mechelec]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Sounds great. You could always connect a fan to the circuit as well ; )

 

[Octopus]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Good luck connecting 2 x 6mm cables in the isolator

 

[telectrix]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

get a 8.5kWatt shower instead. use 1 6mm and keep insulation out of the way. sorted.

 

[Plonker 3]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Good luck connecting 2 x 6mm cables in the isolator

What he said

get a 8.5kWatt shower instead. use 1 6mm and keep insulation out of the way. sorted.

And what he said.

 

[Pete999]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

The mind boggles

 

[sparks1234]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

What ya gonna put on your test sheets?

 

[telectrix]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

and after further consideration, boggles again.

 

[Specialist]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

What ya gonna put on your test sheets?

Doubt he'd be doing test sheets mate, he's a teacher not a sparky.

 

[sparks1234]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Thinking about that, could always put it down as a ring

 

[amlu]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

2x 6mm cables wont fit into 50a switch terminals. better get a small din rail equipped enclosure and join them on a 100a isolator.

 

[Geoffsd]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Just a thought -

9500 / 240 = 39.6A

 

[sparks1234]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

bet a Electrical Trainee could get em in, cut some of them pesky cores out

 

[markc123]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

What ya gonna put on your test sheets?

This is no word of a lie .... I was once presented by a receptionist of a log-cabin park a piece of A4 lined paper that said ....

Circuits :
Sockets - Passed
Lights - Passed
Cooker - Passed

Appliances :
Fridge - Passed
TV - Passed
Kettle - Passed
Microwave - Passed
Toaster - Passed

That was when i was working for my dad before he retired, towards the end of my apprentership - The receptionist had apparantly told him if he wants to rent his log cabin out during the summer he's going to have to get an electrical test done on it - and he presented her with that lol. That's when we were called on his behalf.

Maybe the OP has something similar in mind, lol.

 

[telectrix]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Just a thought -

9500 / 240 = 39.6A

perfectly OK till the insulation monkeys smother the cable.

 

[mikejd]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Thanks for the reply. Please help, I cant see the down side. Each of the two 6mm cables have individual 30A mcb's in the CU. The two 6mm cables fit easily into the 50A isolator switch. If somehow one cable became damaged in the future, then the current draw down the other cable would trip the other 30mcb.
What have I missed?

 

[sparks1234]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

As Tele said, if it was a short run, no insulation you might get away with one cable on the limit but chuck some fluffy stuff on it and start the derating

 

[Alex Ramage]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

:rolleyes4::rolleyes4:

Thanks for the reply. Please help, I cant see the down side. Each of the two 6mm cables have individual 30A mcb's in the CU. The two 6mm cables fit easily into the 50A isolator switch. If somehow one cable became damaged in the future, then the current draw down the other cable would trip the other 30mcb.
What have I missed?

Missed? Poor practice, non standard circuit/cable size, how to test it correctly not to mention the embarrassment of allowing any other electrical professional or inspection authority the satisfaction of outing your handy work. No argument you offer can excuse this as an electrical installation. Installation certificate would be interesting. Would you be so good as to forward us a copy?

 

[Silly Sausage]

Re: can two 6mm csa cables each with 30A mcb in joined at 50A dps to supply 9.5kW sh

Thanks for the reply. Please help, I cant see the down side. Each of the two 6mm cables have individual 30A mcb's in the CU. The two 6mm cables fit easily into the 50A isolator switch. If somehow one cable became damaged in the future, then the current draw down the other cable would trip the other 30mcb.
What have I missed?

Numerous regulations which you need to comply with.
They can easily be found in the latest edition of BS7671.