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I'm in the process of a DIY 400A service upgrade, I roughly wired up the main panel waiting for the utility to schedule the switchover to the new line.

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For now I have installed a single 125A breaker that I will need to continue have power in the house. The black wires come from a box on the inside. I have marked the neutral with some random white tape and one of the phases with duct tape.

The copper wires go to the Ufer ground. As I had wire in excess, I ran two. The city inspector already approved the ground connection but hasn't seen the other wires.

Are the wires tidy enough? Should I square them up more? The 125A breaker output has flat-blade screws like if it was designed in the 19th century - I need to properly torque those down.

What I am concerned about is that this main panel will only be used to install few more 125A breakers (plus the second 200A above). There aren't many neutral connections for larger size wire.

nobody
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Alessio Sangalli
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2 Answers2

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Three problems for sure:

  1. Duct tape is not listed for marking electrical wires. When using tape, you must use UL-listed tape. (The same rule applies to the white tape on the neutral but it looks "close enough" to legitimate electrical tape that an inspector probably wouldn't question it)
  2. Gray is not a valid color for marking hot wires. Gray is reserved for neutral, along with white. There isn't actually a requirement to give distinguishing marks to the two hot wires on a 240V split-phase circuit, so you could just remove the duct tape and be fine.
  3. The #4 ground wire going inside isn't marked. It needs to be marked green.
nobody
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As @nobody points out, get rid of duct tape, mark your grounding wire green. If you notice, right behind where your wires connect to 125A breaker, there is a large gauge lug, possibly 2. There is also a whole neutral/ground bus on right hand side of panel. I would relocate your neutral and grounding conductors to right side, leaving the space on left clear for the remaining conduits. The #4 Grounding Electrode Conductors can be terminated in the bus on the right as well. However I believe you stated you installed 2 Ufer's? If so, you will still need at least 1 driven ground rod, 5/8" x 8' minimum. Code requires 2 grounding electrodes, ONE of which must be a driven ground rod. From what I can see, you should have 5 or so lugs still open that will accept at least 1/0, if not, home Depot carries lugs designed to attach to the bus for extra large gauge connections.

Nec 250.52 and 250.53 cover grounding electrode requirements. A single electrode can only be a rod, pipe, or plate type and to not require a supplemental electrode, must be verified to be maximum 25 ohms to ground. Your concrete encased electrode (ufer) is an acceptable supplemental electrode.

Keith
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