Im looking to add a circuit to this sub panel box but when I opened it up I noticed that the neutral (black) connection bar is connected to the ground bar, as circled in red in the photo. Is this normal? Also what is the orange wire? enter image description here

  • It looks like you are in the UK , so I don't know your codes but on the other side of the pond this is common for the main panel to have both the neutral and ground connected even required. About 18 years ago it became a violation to connect the ground and neutral in a sub panel over here but homes that were wired this way prior to the the change are not required to be isolated like current code requires. Hope this helps.
    – Ed Beal
    Mar 3, 2018 at 0:01
  • Where are you on this planet? Mar 3, 2018 at 1:05
  • This looks like it's actually your main panel -- are there any other panels in the place? Mar 3, 2018 at 2:25
  • There is actually another fuse box in an out building that is first in line.
    – Kokako
    Mar 3, 2018 at 7:13
  • Is there any chance your power company is giving you two phases? Mar 3, 2018 at 8:05

2 Answers 2


Orange wire looks like Orion NZ Ripple Signal. Used to manage peak load and related things. Have a look over this link: Orion Ripple Signal Guide

As far as the grounded neutral I suspect this is a main panel (nz “switchboard”) and not a sub-panel

  • Thanks Stanwood.I think you are correct as that yellow lead goes to the breaker that is used for the hot water heater.
    – Kokako
    Mar 3, 2018 at 21:15
  • Can anyone explain the rationale for a grounded neural system? Interesting that apparently it's not done any more. This box was put in in 1991...
    – Kokako
    Mar 3, 2018 at 21:17
  • The green wire heading out of the bottom should be going to Earth. This gives you some protection from an external surge on the black (neutral) wire. E.g., from a lightning strike on the supply pole. Separately, the metal frames on any appliance are tied to ground wires heading back to that panel. If the red wire (hot) shorts to the frame current will flow back to the panel neutral/ground and trigger the circuit breaker. This protects you from a shock hazard. So in one case we bond earth to neutral. In the other we bond metal frames to neutral. In each case we use a green wire.
    – Stanwood
    Mar 3, 2018 at 21:26

Time to hit the books. Consider at least reading through

NZECP 51:2004 ISSN 0114-0663


  • Thanks Bryce. I have read that guide, but doesn’t go into detail about fuse boxes.
    – Kokako
    Mar 3, 2018 at 7:10

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