electric shower tripping

N

neilyboy

-
Been asked to find out why a new shower is tripping a new cu rcd,
new shower 9.8kw mira
supplied with 10mm T&E
40amp mcb protected by 63a RCD
Its a new cable thats been run in and I have no equipment to test the continuity etc I went right back to basics ,missed out the 45amp DP switch and it still tripped,then wired it straight into the DP isolator switch of the cu and the shower started straight away I should also say that this cu is fed from the main house but the shower did not trip the main cu.
The mira instructions say to fit a 30a rcd

Anyone any ideas ?

Ta
 
Sort by date Sort by votes
Thanks for the reply as I said I have no proper testing equipment I have a fluke ,continuity was fine with this,and yes you are right it is 30ma ....really should proof read posts I'll check the neutral is in the correct bar next time I'm out..
 
Upvote 0 Downvote
ok got that, would this occur even if the cu is split load ?
and if there is an N-E fault elsewhere why is this not tripping the rcd

things were much easier in the 70's sparky wise....a meggar for testing and a wire coat hanger and a piece of string with a plug chain for fishing cables...
 
Upvote 0 Downvote
A 41A load on a 40A ocpd is not a good start!
Without test equipment you are going to waste a lot of time and effort.

If I've read the op correctly, which I hope I haven't, you have bypassed the protective devices by connecting the circuit directly to the main switch of the CU?
 
Upvote 0 Downvote
Think you've read it right Dave, if not we both need to learn to read. That's how I read it as well.

I don't really understand going to look for a fault without test equipment either, maybe I'm getting too old for this.
 
Upvote 0 Downvote
Really should take more notice but I was more concerned theat the rcd was tripping and didnt (or cant )remember if both had tripped I have a feeling the the mcb is 40a as it was one of those pre-populated CU's that he bought
and Ive just done a quick calc for a 9.8kw appliance and its 40.833333333a...
 
Upvote 0 Downvote
In reply to the above ,I'm doing a pal a favour in trying to find the fault, the original installer is not returning his calls
I think some of the problems have arisen due to my pal buying the materials himself to save money.
and ..FYI I don't have any test equipment as I've been effectively off the tools since 1986..save for the odd light fitting and extra socket
 
Upvote 0 Downvote
yes I agree but we didnt have all the all singing and dancing equipment in the late seventies /early eighties it was a case of disconnecting everything and starting from the cu ....
we only had one megger between two of us when on the tools, I completed a pyro installation and the only way I could bell out the cores was to connect to to the supply and hope that the cores had sealed properly and the pot was on straight...
 
Upvote 0 Downvote
You don't need anything all seeing & dancing just an Insulation tester & maybe a Clamp meter to check Earth leakage.
If the installer left it like that though, you have to wonder what else you might find.
 
Upvote 0 Downvote
neilyboy said:
Been asked to find out why a new shower is tripping a new cu rcd,
new shower 9.8kw mira
supplied with 10mm T&E
40amp mcb protected by 63a RCD
Its a new cable thats been run in and I have no equipment to test the continuity etc I went right back to basics ,missed out the 45amp DP switch and it still tripped,then wired it straight into the DP isolator switch of the cu and the shower started straight away I should also say that this cu is fed from the main house but the shower did not trip the main cu.
The mira instructions say to fit a 30a rcd

Anyone any ideas ?

Ta
Click to expand...
Well wiring it into the CU M/S and it wont trip, cus there is nothing to trip
 
Upvote 0 Downvote
I dont have a megger, I have a fluke, Installation practices of 40 odd years ago are still practiced today,its the way they are installed ie bad workmanship that cause the problems,wiring systems have not changed since I was on the tools but certain regs have,earthing,testing,circuit discrimination I could go on but ultimately most of it is down to bad practice.
I would have had my a**e booted from my journeyman for some of the installations I have seen
 
Upvote 0 Downvote
davesparks said:
You don't need all singing, all dancing test gear, the vast majority of fault finding jobs can be done with a simple megger.

There's a good reason that the practices of 40odd years ago are no longer acceptable, they are dangerous and have been responsible for many injuries.
Click to expand...
Megger Dave tut tut next you will be telling us you use a Hoover:D
 
Upvote 0 Downvote
Specialist said:
????? To the above.

When you say you've got a Fluke, do you mean a multimeter ?
Click to expand...
yes, yes...but fluke were the gold standard in my days multi meters are available for less than a tenner these days
Specialist said:
????? To the above.

When you say you've got a Fluke, do you mean a multimeter ?
Click to expand...
not sure what the ???? are but if we needed to test an installation we asked for the megger not the insulation resistance tester it came in a nice grey leather case and had a wind up handle
 
Upvote 0 Downvote
The question marks were in reply to your post about knowing what they were called, after Westy joked about Dave telling us to use Hoovers.

As for the fluke, don't really think it's going to help you out here.

Yep know all about wind up Meggers, still had one until a short time ago. Cut my teeth with fault finding using a Drummond probe, Avo 8 & Megger. The Avo & Megger had to be signed in / out of stores every time.
Oh & don't forget the ubiquitous neon screwdriver.
 
Last edited by a moderator:
Upvote 0 Downvote
Wonder if the OP is charging for this?

So its a recent install, the customer bought the kit, the installer isn't returning calls, the OCPD may be too low, we don't know if the RCD or MCB are tripping.

We do know the person fault finding doesn't have the appropriate kit.

Has it ever worked?

Did the installer provide a cert?

Wonderful!
 
Upvote 0 Downvote
Q
Murdoch said:
Wonder if the OP is charging for this?

So its a recent install, the customer bought the kit, the installer isn't returning calls, the OCPD may be too low, we don't know if the RCD or MCB are tripping.

We do know the person fault finding doesn't have the appropriate kit.

Has it ever worked?

Did the installer provide a cert?

Wonderful!
Click to expand...

Same old story buddy, nothing changes :)
 
Upvote 0 Downvote

Similar threads

C
2nd CU fed from existing CU
Replies
9
Views
221
newfutile
newfutile
G
  • Question Question
UK RCD on bathroom ceiling?
Replies
7
Views
903
gggrrr209
G

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Green 2 Go Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses Heating 2 Go
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

YOUR Unread Posts

Daily, weekly or monthly email

Receive a daily, weekly, or monthly email containing a digest of new and recently updated threads.

Thread starter

N

neilyboy

-
Joined

Thread Information

Title
electric shower tripping
Prefix
N/A
Forum
UK Electrical Forum
Start date
Last reply date
Replies
59
Unsolved
--

Thread Tags

Tags Tags
electric shower tripping

Advert

Thread statistics

Created
neilyboy,
Last reply from
davesparks,
Replies
59
Views
14,342

Advert

TrueNAS JBOD Storage Server

Tilers | UK Tiling Forum | Tilers Forums | Find a Tiler
Plumbers Forums | Plumbing Advice | Gas Forum
Back
Top