Freezer circuit

[mercury]

From my understanding a freezer should be on a non RCD protected circuit.

Currently i am having garage electrics installed with a Volex Garage Unit 40A 30mA RCD +1 X 6A, 1 X 16A SP MCB. Obviously the circuits will be protected by the rcd but is there any way of putting a freezer on a separate radial as there are no spare ways in the garage cu for a separate circuit.
(For info the garage cu is supplied via 6mm 3core SWA from the non RCD side of the main CU.)

 

[racket]

Are you doing the work yourself, cos if you are be prepared for some reg's reading sparky to come along and start ranting about part P If not then should'nt your spark be able to tell you

 

[mercury]

Yes will be carrying out installation myself, and yes have been through the appropriate channels with regard to local building regs.(Had extension built so submitted electrical work at same time) All Bldg regs want at end is qualified lecy to inspect and test (periodic insp & test form).
i'm sure someone will tell me different but this is what MY local Bldg control require.

 

[Steve]

In that garage consumer unit, scrap the incoming RCD. Have a main switch. use one MCB for the freezer (permenantly wired in), and a single module RCBO for the sockets. Put the lights on an FCU on the RCBO circuit.

 

[mercury]

Cheers Crafty.
A slight change to the subject but does the wiring for the sockets and lighting in the garage require protection in conduit or trunking or can the t&e be fixed directly to wall/joists so long as its adequately clipped.

 

[dingbat]

The RCBO will probably cost you twice as much as the garage unit.

It is perfectly okay to surface-clip twin and earth cable, as the grey sheathing is there for mechanical protection. Use metalclad sockets and 20mm stuffing glands for the entries.

http://www.tlc-direct.co.uk/Products/AA3356.html

http://www.tlc-direct.co.uk/Main_Index/Cable_Accessories_Index/Gland_Compression_Nylon_1/index.html

 

[mercury]

Am I being too picky about having the freezer on a seperate circuit. Do other people bother or do they just leave it on the RCD side. Has anyone had any problems with the freezer being on the RCD circuit.

 

[Steve]

Our fridge/freezer is on an RCD. In the last 6 months (since consumer unit change) we haven't had a problem with it.

There are 2 thing to watch for when putting a freezer on an RCD.

1. Earth leaks from the motor in the fridge/freezer. Over time, the carbon brushes can wear down and the dust creates small leaks to earth, which can trip a sensitive RCD (30mA). This is only really a problem with old motors and very large motors, but it does happen, and I wouldn't want to risk loosing all that food!

2. Other appliances tripping the RCD. Obviously when this happens, and nobody is about, you could loose the contents of the freezer/fridge. In a shed, where the freezer is the only permenant appliance, this isn't a problem because when other appliances are in use (lawnmowers etc), someone will be about to reset the RCD and nothing will be lost.

In the end, its really a personal choice. Its up to you.

 

[dingbat]

But is it a good idea to house an ordinary domestic freezer in an outbuilding anyway?

http://www.ior.org.uk/ior_forum.php?r=ULEMQWJVAG&id=Z6EN59GEAE

 

[mercury]

Thanks again for swift replies
Will try freezer on rcd circuit for now.
Understand what your saying dingbat but due to lack of space it has to go in the garage (2nd freezer anyway, main one in kitchen)

 

[Chris.J]

A friend of mine has his freezer in his garage, and so, as he does'nt go out there every day, has a 8 watt high-E lamp on the same circuit, to monitor the power (visable through a window).
Also usefull when he's away; neighbour can monitor without having to go in.

 

[racket]

Earth leaks from the motor in the fridge/freezer. Over time, the carbon brushes can wear down and the dust creates small leaks to earth, which can trip a sensitive RCD

I don't think so. There are no carbon brushes in a fridge motor.

 

[JohnD]

You can also get a freezer alarm which sits on the circuit and starts bleeping if the power is cut. I suppose this would be simpler if the RCD was at the house end, not in the garage (which I personally prefer in case someone damages the cable going to the garage)

 

[Steve]

Earth leaks from the motor in the fridge/freezer. Over time, the carbon brushes can wear down and the dust creates small leaks to earth, which can trip a sensitive RCD

I don't think so. There are no carbon brushes in a fridge motor.

where did i get the carbon brushes idea from then?

EDIT: oh hang on, was it washing machine motors i was thinking of?

 

[JohnD]

were you thinking of a large commercial freezer?