TS, I might be able to give u better solution. Before that, I'm suspecting that u found the wrong fault.

- proper tools to use is insulation tester instead of DVM.
- Incoming MCB or Outgoing MCB trip?
- Did u manage to locate all the SSO looping from the same shorted circuit?
- Is the SSO the 1st point or last point or intermediate point?
- Any conductivity between L/N with E?
- Using GI or uPVC conduit?

---

Added on October 27, 2011, 12:02 amHow sure are you the ELCB trip is due to fault from that water heater since it will trip even when its not on? ELCB tripping on and off is a little difficult to troubleshoot.

If you are sure about it, get the wireman to do insulation test on that cable.
Other possibilities is the water heater giving problem. Try plug in other appliances to the socket, possibly, suggest to plug in 2 Nos 100W incandescent bulb connected in series to the socket to see if it lights up or trip.
Else, neutral cable returned to the wrong ELCB. This happen if you have 2 Nos. of ELCB in the whole house, either in the same DB or inside 2 DB at ground floor and 1st floor.
Else, ELCB having problem


This post has been edited by pky: Oct 27 2011, 12:02 AM

Yes, it shouldn't trip. So, have to determine the problem by doing troubleshoot, from the end point of the circuit to the 1st point, eg. :
1) Is other appliance connected to the same source giving the problem
2) Is the water heater giving the problem?
3) Is the water heater SSO giving the problem
4) Is the water heater switch giving the problem
5) Is the wiring giving the problem
6) Is the ELCB giving the problem

---

Added on October 31, 2011, 7:10 pm

---

Added on October 31, 2011, 9:31 am
actually i also confuse about this, cause the water heater seem working fine when the wireman connect back all the wire, it only trip after several hours but that is when the heater is off. would suggest what u mentioned to the wireman see what is he comment. thanks lot

[/quote]

Just for your info, not all wireman have insulation and most probably don't know what is an insulation tester. Does it repeat the same thing the next day or the ELCb forever can't turn on after trip?

This post has been edited by pky: Oct 31 2011, 07:10 PM