Given that your electrician has already questioned the idea of a separate consumer unit, brace yourself for further negative response about the need for all this, culminating in outright ridicule when you mention using 10mm cable.
Worth shopping around for a sparky who is not doing the whole thing whilst cursing you under his breath, I think.
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Thats because the electrician isnt an audiophile.
If you just use a spur on the same domestic CU, your system will still be prone to mains borne ânoiseâ from domestic white appliances, RFI etc.
There is a good reason why most decent recording studios have appropriate mains power supplies.
I have used both and can confirm that a seperate dedicated CU connected to the meter does make a huge difference.
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Looking back over this thread I have spotted a misleading typo in my earlier comment. The end of the above sentence should of course read RCB (or MCB dependant on the regs at the time)
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I have never heard of power amps/psuâs etc causing the breaker to trip when powering on. If all is correct with the mains installation surely that shouldnât happen?
This can happen if you are running an active system with three powerful power-amps,âŚand turn them on too quickly.
/Pederđ
It used to happen to me perhaps 50% of the time until I put in a type C, and it has never happened since.
100%, I have type Bâs & I get a trip if it turns all the Naim boxes on simultaiously as would be the case in a power failure & Iâm not aroundâŚ
I have a big house project starting in a few months & Iâve specâd type Câs - RCCB for the power isolator now comes as standard with the new 18th edition regs. And as no one has mentioned it, RCCBâs or RCCOâs are required for lighting in the 18th regs as is the need for non-combustible (not plastic) CU boxes.
HH said that Naim advised him years ago to run a 10mm/2 cable from a separate CU and daisy chain the sockets or use a mains block.
I now intend to do that and daisy chain 2 unswitched double MK sockets.
Please let me know if anyone has any specifics on how that might be made to work best.
I notice from an earlier comment that you are using a single outlet CU, ie one radial powering the whole system. Perhaps that has a bearing on the tripping issue, having a higher load on a single radial/breaker as apposed to the separation of multiple radials?
When the power amp is turned on, the rest of the system is inactive, so there is little current being drawn by anything else. So I think itâs just the rush of current drawn by the amp that does it.
Daisy chaining or rather wiring more than one socket in parralel can be a challenge with 10mm cable. I have found that the terminals on MK logic sockets for example dont take 2 Ă 10mm cable with ease and the grub screw doesnt always grip the cable securely, its not designed to take that gauge of cable. Ideally an unbroken run of cable across the terminals is desirable but working with 10mm again makes this a challenge. Then assuming you can overcome those issues its then a real pain to dress 10mm cable inside the mounting box.
(If you can come across them the older MK, pre Logic, sockets IMO are better as they had much larger cylindrical terminals that would happily take thicker gauge cables)
I have tried the above and most variants over the years and personally would go the multiple radial route. If your going to install a seperate CU its not much of a step further.
One other thought, if you have a single radial terminated in a single socket and then use a mains distribution block, your whole system is subject to the choke of the 13amp fuse in the plug for the distribution block.
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Yes, thatâs why Iâm not planning to use a mains distribution block.
Thanks - v useful information.
Jim
I used a Cooker outlet box when I installed a 10mm/2 radial for someone, it connected up two short 4mm/2 tails into double sockets.
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Fancy a mini âwiring breakâ in Lancashire?
All the bacon sandwiches you can eat - plus as many âuniversal shopping vouchers bearing a picture of the Queenâ as you would likeâŚ??
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Tempting as your bacon sarnies might be, my Part P Cert ran out many moons ago.
JimDog, if you go back, youâll find thatâs what Iâve been advising you to do. Daisy chaining two or more sockets with 10mm2 is difficult and thatâs where the problem lies. It needs to be done carefully and properly. The old Crabtreeâs terminals (not sure of the recent ones) could be filed slightly to accommodate the two wires, but finding that limit of tolerance took a lot of thought and then there was always a tiny bit of doubt after assembling the completed wiring into the mounting box. This is why I developed copper rails from C103 copper, but thatâs another story. Buy a Crabtree and an MK and in your own time, see if/how you can accommodate two 10mm2 cables.
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Another option is to use a Henley block to split the 10mm cable at a convenient point and run two cables to two sockets. Daisy chaining 10mm cable and squeezing it all into a back box is a struggle, so it eliminates that issue.
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Just a word of caution. Beware DIYing, I used to do it and was able to experiment a lot as a result, but that was when regs were less strict.
Nowadays all electrical work, even just adding some extra sockets, must be carried out by a Part P qualified electrician and signed off as compliant. If not, you may find yourself on a sticky wicket with your buildings insurance.
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Yes - not to mention the small matter of my total lack of knowledge and skills in the domain of electrical wiring!
And a criminal offence with a maximum fine of ÂŁ5000.