why on earth

[s.keech]

Hi just been called to a 1960's concrete flat to move a couple of lights and nderfloor heating in the bathroom. The c.u is a metal box with rewirables,very old. The red and black cables are running through metal conduit but there is no earth. Does this mean that the conduit is used as earth. I have looked in the old sockets and they have no c.p.c nor do the lights. I know bathrooms have to be notified to. It also has to be rcd protected to. How would i check continuity,wander lead connected to metal box and check all points or wander lead on m.e.t. There is no earth coming from m.e.t to the metal c.u box though. Is this how they done things before.
Have advised that needs a new c.u but would this need a complete rewire to comply or can i still use the metal conduit as earth.
Any info needed please
Steve

 

[telectrix]

if the conduit gives goor R2 readings, as you say, using a wander lead, then use it. the MET will be the earth bar in the CU. are the cables PVC or VIR? if PVC and your IR readings are OK< then they can be left .

 

[worzol99]

Oh dear, sounds like a old council flat did some rewires on these years ago. Any adjustments would most likely have to be surface mounted.

 

[snowhead]

I did miles of conduit and trunking installs in the late 60's / 70's with using the conduit and trunking as earth.
Very common way of doing it.

 

[telectrix]

what you need to bear in mind, when using conduit as cpc, is that you must fit fly leads from back boxes to faceplates, as this is the only way of connecting the cpc to the accessory. ( not required with plastic switches , but necessary on all sockets )

 

[s.keech]

pvc but what about rcd issue?

 

[trev]

what you need to bear in mind, when using conduit as cpc, is that you must fit fly leads from back boxes to faceplates, as this is the only way of connecting the cpc to the accessory. ( not required with plastic switches , but necessary on all sockets )

The bolts are conductors Tel
Yeeeeeeeeeeehhhaaaaaaaahhhhh!!

 

[telectrix]

you would fit RCD protection where required. as most cables buried are protected by earthed mettallic conduit, you would only need RCD protection on socket oulets and all batrhroom circuits.