About 3 months ago my wife and I bought a house built around 1945, it has 2 wire cloth wiring for the most part, but has some newer rubber romex mixed in here and there, my question is about the electrical panel, the grounds and neutrals are tied into the same buss bar, also, their is no ground rod. I understand this is potentially very dangerous, What exactly do I need to do to fix this? Also if you see any other problems with my panel please feel free to point them out, thanks in advance.
Grounds and Neutrals, What To Do? (pics inside)
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In the main panel (with the first master disconnect switch/main breaker from the meter) grounds and neutrals should be combined. THe neutrals must go to the terminal strip (bus bar) to which the incoming neutral is attached, or an additional metal bar or thick wire (at least #6 I think) must connect that strip to any other strip to which branch circuit neutrals are attached. Although the strip to which the incoming neutral is attached must be bonded to the panel itself such as using a screw that fastens or digs into the sheet metal, such screws are not sufficient to connect (bond) an additional strip holding neutral wires.
On top of all that a #6 copper wire must connect the fat incoming neutral or its terminal strip in the main panel to a pair of ground rods six feet apart and also to the incoming cold water pipe (if metal) within 5 feet or before the meter whichever is closer to where the pipe enters the house. (#4 from panel to water pipe service over 100 amps)
In subpanels (where there is a master disconnect switch further upstream) the neutrals and grounds must be on separate terminal strips and the strip for the neutrals must not be bonded to (make contact directly or indirectly) with the back of the panel or other exposed metal objects. For a subpanel in a separate garage or building a ground rod is required and the wire connects to the ground terminal strip.
If neutral wires have to be moved to another terminal strip and don't reach, splice on individual continuation wires (pigtails). If ground wires have to be moved then some may be taken off and combined and just one pigtail of the larger(est) size of any in the bundle continues on to another terminal strip.
Each neutral wire must be in its own hole in the bus bar strip. Two ground wires of the same size can share a hole.
While you are at it, you might as well be sure that all the screws and set screws holding wires in place are tight. Have an experienced person check and tighten the big set screws holding the fat feed wires in place.
What is in the box next to the meter?
On top of all that a #6 copper wire must connect the fat incoming neutral or its terminal strip in the main panel to a pair of ground rods six feet apart and also to the incoming cold water pipe (if metal) within 5 feet or before the meter whichever is closer to where the pipe enters the house. (#4 from panel to water pipe service over 100 amps)
In subpanels (where there is a master disconnect switch further upstream) the neutrals and grounds must be on separate terminal strips and the strip for the neutrals must not be bonded to (make contact directly or indirectly) with the back of the panel or other exposed metal objects. For a subpanel in a separate garage or building a ground rod is required and the wire connects to the ground terminal strip.
If neutral wires have to be moved to another terminal strip and don't reach, splice on individual continuation wires (pigtails). If ground wires have to be moved then some may be taken off and combined and just one pigtail of the larger(est) size of any in the bundle continues on to another terminal strip.
Each neutral wire must be in its own hole in the bus bar strip. Two ground wires of the same size can share a hole.
While you are at it, you might as well be sure that all the screws and set screws holding wires in place are tight. Have an experienced person check and tighten the big set screws holding the fat feed wires in place.
What is in the box next to the meter?
So from what your saying the grounds and neutrals end up tied together in the end anyway? What about not having a ground rod?
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Main disconnect?
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If that’s the main disco outside, then yes the panel inside is a sub-panel (feeder panel). Yes, the grounds and neutrals would have to be separated (bonding strap removed, ground bar bonded to case, etc.)
The outside disco would get the GEC to the ground rods, water pipes, etc., and a 4th wire (grounding wire) would have to be brought into the panel inside from the disco outside.
The outside disco would get the GEC to the ground rods, water pipes, etc., and a 4th wire (grounding wire) would have to be brought into the panel inside from the disco outside.
Yeah, this panel does not appear to be the service equipment (the disconnect outside is), so it requires a 4-wire feed with an isolated neutral bar. That's kind of a PITA to retrofit here, but definitely possible and only an afternoon project if you get all your ducks in a row before you start.
If the box next to the meter has a master on off switch (which would then be the main disconnect) then it would be worthwhile to find some way of (the name of the game now becomes) not upgrading the fat cable down to the breaker panel pictured.
Simply moving the neutrals to the right bus bar and (if there isn't enough room) moving some grounds to the left bar can be done casually not requiring permit and inspection and the panel would still be grandfathered so as not to need a new 4 conductor fat cable. YOu might need to contact your town inspection department to see what projects are big enough to lose grandfathering. Hopefully replacing the cloth wire with Romex little by little won't upset that.
You would also want to check previous permit and inspection records. If the panel and previous work required a permit when done and was done without a permit then there is no grandfathering..
Simply moving the neutrals to the right bus bar and (if there isn't enough room) moving some grounds to the left bar can be done casually not requiring permit and inspection and the panel would still be grandfathered so as not to need a new 4 conductor fat cable. YOu might need to contact your town inspection department to see what projects are big enough to lose grandfathering. Hopefully replacing the cloth wire with Romex little by little won't upset that.
You would also want to check previous permit and inspection records. If the panel and previous work required a permit when done and was done without a permit then there is no grandfathering..
A feeder panel in or on the same building has required a 4 wire feeder for many years that pre-date this installation. The conduit looks like PVC so that cannot be used for the grounding.
Since a conduit is already in place it may be large enough to add the needed fourth conductor.
You need a fourth wire from the disconnect to the panel connected to the buss on the left which becomes the equipment grounding buss. The bonding jumper, connection located at the center of the right hand buss gets removed leaving that buss as the neutral buss to which all neutrals are attached. Grounding electrode conductors from ground rods, metallic water pipe or ufer if available are connected inside the disconnect to the incoming neutral.
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