RCD

[andy]

roughly how much should a 100 (or 80)A, 100mA time delay RCD cost?

i was expecting about £40, but went to a wholesaler earlier and was told it would be about £70-80!

is this reasonable?



also, is there any thing in the regs to say i can have 2 RCD's in a consumer unit (what i am not planning on doin is havin a main isolator feeding 2 RCD's. 1 RCD will protect sockets etc and another for the lights etc). can this be done?

 

[Careful_Bodger]

£70-80

Yup - a well known supplier mentioned often on this forum also charges about this amount.

 

[plugwash]

also, is there any thing in the regs to say i can have 2 RCD's in a consumer unit (what i am not planning on doin is havin a main isolator feeding 2 RCD's. 1 RCD will protect sockets etc and another for the lights etc). can this be done?

nothing wrong with that. Some suppliers (crabtree i think) even provide kits to do that. Without a kit the only potential issue is that you will need to use some thick singles to go from the main incomer to the two rcds and you may have trouble getting theese in the outlet terminals of the incomer.

 

[andy]

nothing wrong with that. Some suppliers (crabtree i think) even provide kits to do that. Without a kit the only potential issue is that you will need to use some thick singles to go from the main incomer to the two rcds and you may have trouble getting theese in the outlet terminals of the incomer.

will prob do that instead. thanx.

why are the time delay RCD's so much compared to standard RCD's?

 

[plugwash]

i think its because they are a low volume product

TT supplies are pretty rare.

 

[andy]

i think its because they are a low volume product

TT supplies are pretty rare.

how often do TT supplies get changed to TNCS? the house is fed from an underground cable and i kno there is a substation close (approx 80-100M direct from the house, but the cable run will prob be longer)

EDIT: its a 1930's house if that makes any diference. also, the main supply coming in seems pretty thin... about the same diameter as a 2.5mm arctic cable

 

[plugwash]

happens quite a lot at least with overhead TT supplies

ask your rec they should send someone out to tell you (if they won't then ring again play ignorant and say you think you have no earth)

from the reports i have seen on forums the price for a conversion ranges from free up to about £100

 

[andy]

thanx. will prob phone them and ask. worth a try

 

[ban-all-sheds]

Get your main bonding up to spec first, or even over-spec, as some DNOs want 16mm² for a PME, even though 10mm² is compliant.

If you wait until they ask for it to be done they might twig that it's a DIY job, and get all huffy.