Garage electrics

[jswagger]

Hi,


Further to a previous thread on the subject I’m planning on putting in the electrics in my new garage and wanted to see if anyone had any advice/warnings before I send the form off to the council. I have done quite a lot of home electrics in the past but have never done any outside electrics before or anything involving SWA cable. The garage is 25m from the house and will require 4 x double sockets and 4 x strip lights.


I plan to install a 2 way consumer unit in the garage, comprising 40A 30mA RCD, 1 x 6A and 1 x 16A Type B MCB. I intend to run 6.0mm SWA from the garage to eventually connect to a spare MCB slot in the house consumer unit. As the house consumer unit is at the front of the house and the garage at the end of the garden, rather than run SWA all the way to the house consumer unit I’ll run 6mm Twin +E from the house consumer unit to under the floor in a rear bedroom ( maximum run 5 metres). Then the twin + E will be connected to the incoming SWA using a chocolate block inside a suitable metal box.

Any advice on what size MCB I should use in the house consumer unit? Also other consumer units seem to have the non RCD side clearly marked, but my MK sentry doesn’t, is there any way to tell which is the non RCD side?


Thanks very much for your help.

 

[ricicle]

You sounded fairly competant up until you said...

Also other consumer units seem to have the non RCD side clearly marked, but my MK sentry doesn’t, is there any way to tell which is the non RCD side?

The RCD side will have such things as sockets, showers on it
Non - RCD will have lighting, immersion,cooker (if no socket on it)

The non-RCD circuits should be between the main switch and the RCD and then the others after the RCD.

 

[jswagger]

You sounded fairly competant up until you said...

Also other consumer units seem to have the non RCD side clearly marked, but my MK sentry doesn’t, is there any way to tell which is the non RCD side?

The RCD side will have such things as sockets, showers on it
Non - RCD will have lighting, immersion,cooker (if no socket on it)

The non-RCD circuits should be between the main switch and the RCD and then the others after the RCD.

even fairly competent is a compliment!

Thanks I'll have a look.

 

[davy_owen_88]

On MK boards, the left hand side is the non-RCD side:
(left to right)
Main switch - non protected MCB's - RCD - RCD protected MCB's.

Use a 32A MCB on the non-rcd side.

Everything else sounds fine. Remember to use tape to note the presence of the buried cable (600mm deep).

 

[jswagger]

On MK boards, the left hand side is the non-RCD side:
(left to right)
Main switch - non protected MCB's - RCD - RCD protected MCB's.

Use a 32A MCB on the non-rcd side.

Everything else sounds fine. Remember to use tape to note the presence of the buried cable (600mm deep).

Thanks.

Out of interest this is how the MK sentry unit runs from left to right:

Main switch
Shower
Ring circuit (g floor)
ring circuit (1st floor)
Cooker (has a socket)
Spare
Lights
Lights (1st floor)
Smoke alarms
Spare

 

[davy_owen_88]

Out of interest this is how the MK sentry unit runs from left to right:

Main switch
Shower
Ring circuit (g floor)
ring circuit (1st floor)
Cooker (has a socket)
Spare
Lights
Lights (1st floor)
Smoke alarms
Spare

Are you sure? Where is the RCD unit?

Here's one RF did earlier:

As you can see, the RED section is not protected and the GREEN section is.

 

[jswagger]

Out of interest this is how the MK sentry unit runs from left to right:

Main switch
Shower
Ring circuit (g floor)
ring circuit (1st floor)
Cooker (has a socket)
Spare
Lights
Lights (1st floor)
Smoke alarms
Spare

Are you sure? Where is the RCD unit?

Here's one RF did earlier:

As you can see, the RED section is not protected and the GREEN section is.

Mines different to the one in the picture. It just has a row of MCBs with the exception of the shower taking up the space of two slots and marked RCBO. I've no idea how old it is as it was here when we moved in.

 

[RF Lighting]

Sorry the pic is so small, best it could do

Is this the type of CU you have?

 

[breezer]

delete please

 

[jswagger]

Sorry the pic is so small, best it could do

Is this the type of CU you have?

From what I can make out it looks the same, only difference is that the main switch is on the left hand side (or your pic is upside down!)

 

[davy_owen_88]

Mines different to the one in the picture. It just has a row of MCBs with the exception of the shower taking up the space of two slots and marked RCBO. I've no idea how old it is as it was here when we moved in.

Well that would explain why your CU doesn't state the RCD/non-RCD side - there is no RCD side.

You really should have an RCBO protecting the ground floor circuit too.

 

[jswagger]

Mines different to the one in the picture. It just has a row of MCBs with the exception of the shower taking up the space of two slots and marked RCBO. I've no idea how old it is as it was here when we moved in.

Well that would explain why your CU doesn't state the RCD/non-RCD side - there is no RCD side.

You really should have an RCBO protecting the ground floor circuit too.

I'm thinking of having the whole house redone at some point in the future. For the time being though does that mean I can use either of the spare MCB slots?

Is that quite an old design of consumer unit?

Thanks for all your help.

 

[davy_owen_88]

Yes, you can fit a suitable MCB into any of the spare ways.

RCBO's are perfectly acceptable, and if it wasn't for the price they would be far more common. I would still consider fitting an RCBO on the downstairs ring circuit until you decide to get the rest seen to.

 

[jswagger]

Yes, you can fit a suitable MCB into any of the spare ways.

RCBO's are perfectly acceptable, and if it wasn't for the price they would be far more common. I would still consider fitting an RCBO on the downstairs ring circuit until you decide to get the rest seen to.

What size MCB would recommend?

 

[davy_owen_88]

32A