Hydra & Spur

Posted by: GraemeH on 31 August 2010

My Hydra was a 1 into 4 when I had the 135's but since aquiring a 300 one head has been unused. For neatness and to assuage the niggle of doubt I changed it for a 3 headed Hydra at the weekend. This is definitely the thing to do as it has brought a subtle but noticeable lift in clarity - Don't ask me why but it is better.

Yesterday a 10mm spur went in to a single switchless socket....I really should have made this £35 upgrade years ago!

G
Posted on: 31 August 2010 by vandergraafuk
I agree wit the 10mm2 spur. I had 6 put in after splitting the meter tails during the rewire of my house by a qualified sparky. I now have a dedicated CU for the HiFi and one for the rest of the house. Another change I had done by the lecky board is had the incoming fuse changed from 60A to 100A. A great upgrade IMHO.
Posted on: 31 August 2010 by ray davis
i change 60amp fuses for a past time to a 100amp fuse.

Splitting the meter tails i am a bit confused on that one. Do you mean the outcoming tails go into a separate blocks phase and neutral then into separate consumer units?
Posted on: 01 September 2010 by vandergraafuk
Hi Ray,

Yes you are correct the the meter tails after the meter into a splitter block the one set of tail of to the normal house CU and the other pair to a dedicated CU for the HiFi.
Posted on: 01 September 2010 by ray davis
same as i have luckily working for the electric company , cost me bugger all. There are loads of things you can do to the incoming supply to make everything else safer.

The 100 amp fuse some times is a debatlabe issue. The fuse is there to protect you from faults on the distrubution network. It also is there to protect the network from any faults that occur on your own internal electrics at home.

The now normal PME is not as good as everyone first fault. SNE is coming back again with a four core mains cable, so that any fault goes to earth not back along the neutral.
Posted on: 01 September 2010 by vandergraafuk
My house was rewired 2 months ago and the electrician as part of the job had it changed to PME. When he explained to me what that was I did occur to me that faults returning on the neutral was slightly odd. But hey I am not qualified in this field and who was I to argue. What other tweaks can be done. Obviously carried out by a qualified sparky. Not sure if mods will allow this type of thread. Any mods care to comment?
Posted on: 01 September 2010 by ray davis
a qualified sparky will know his electrics inside out. PME and SNE depend on the cable coming into your property. PVC sheathed cables are usually PME normal concentric cable. There is also PVC sheathed SNE cable split concentric. Then the good old Paper lead steel armoured cable. The biggest problem sometimes with the Armoured cable is that the steel armours are used as the earth. The lead underneath the armours is the earth. PME can be offered if the Earth loop is below .35 ohms thsi is done at the cutout with only the phase and neutral in the cutout no earth.

Above .35 ohms PME should not be offered and sometimes an RCD can be fitted.

On paperlead cables the earth loop should be below .80 ohms.

I am just trying to explain how things are on different cables.

IF this post gets removed or modded fair enough. Just a little bit on PME and SNE.
Posted on: 01 September 2010 by count.d
quote:
Originally posted by vandergraafuk:
Hi Ray,

Yes you are correct the the meter tails after the meter into a splitter block the one set of tail of to the normal house CU and the other pair to a dedicated CU for the HiFi.


Tap off from the splitter block to the main house cu, but keep the cable to the hifi consumer unit uncut.
Posted on: 02 September 2010 by ray davis
if you can use 25mm copper tail, they must be double insulated as well. All Tails from meters are double insulated.