Comments by "Ted Sanders" (@surferdude642) on "Sub Panels Explained - Why are neutral and ground separated?" video.

  1. ​ @Gt92279 Some of it would, but maybe not enough to trip the breaker. In the meantime you'd have parallel paths of current and that's a shock hazard. This condition in electrical wiring is known as "objectionable current".
    2
  2. No, because you're measuring the voltage (potential difference) between opposite poles. One is +120v and the other is -120v and 0v is the mid point (neutral). If you measured a point on one one of the bus bars and another point on the same bus bar, then you'd get 0v because there's no potential difference. As an analogy, say if you're at home and you had to drive somewhere. Your home is 5 miles from the interstate highway and your destination is 5 miles on the other side of the highway, total is 10 miles.
    2
  3. The ground it shares is the equipment ground aka the EGC, equipment grounding conductor. The grounding electrode is part of the GEC, grounding electrode conductor. You need a grounding electrode, ground rod in each building to protect them from lightning strikes.
    2
  4. That's a good observation you made and it doesn't sound right. You should call an electrician to have a look at it.
    1
  5. No, you will have 240v only.
    1
  6. The current always tries to return to its source, which in this case is the transformer. In a natural condition such a lightning strike, the source is the earth, and the ground rod provides that path if the lightning strikes the building.
    1
  7. Because the breaker would trip immediately.
    1
  8. Then a ground fault in the circuits attached to the sub panel cannot be cleared and metal parts will remain energized.
    1
  9. You need to have a ground and neutral bond in the main panel or first disconnect means so the current returns via the neutral wire to the transformer and trips the breaker. Otherwise all the metal parts will remain energized.
    1
  10. Why do you think that?
    1
  11. I don't think that it is. The point of the ground wire is to provide a low impedance path in case the hot wire contacts a grounded metal case. The neutral wire is not involved in this scenario. If the ground wire contacts say the neutral screw on a receptacle the return current will be shared between the neutral and ground and have parallel paths of return current which is also bad because of a potential shock hazard. If you have a GFCI receptacle in the circuit, it probably wouldn't reset or it would trip when you plugged something in and turned on the switch. The insulation or not has nothing to do with it.
    1
  12. To your first question, it does sound correct, but I can't be 100% certain without seeing it. You may want to call an electrician to verify that. The answer to your second question is absolutely not. The neutral and ground connection must only be made at the first disconnect, usually that would be the main panel. Anywhere downstream, the neutral and ground must be separated and under normal operation, the ground wire must not carry any current and the neutral wire must carry all of the return current to the only ground/neutral bus in a 120 volt circuit. The one exception would be in a multi wire branch circuit, the neutral wire will carry only the unbalanced load and the rest would return on one of the hot wires. You can't carry current on both the neutral and ground because it would a parallel path and may not trip the breaker. It would be a shock hazard since all the metal components would be energized.
    1
  13.  @ShyRage1  You said that you added a ground bar to the sub. I don't get that, because your sub panel must already have a ground bar. Did you need a second one? The ground bar must be grounded to the panel frame, but the neutral bar must be isolated from the frame and the ground bus bar. You said previously that the main panel has a crossing bridge joining the two bus bars. Are ground and neutral wires sharing those bus bars or are they occupied by neutral wires only?
    1
  14.  @ShyRage1  So all the circuits in the sub panel are ungrounded then the receptacles should be 2 prong or replaced with a GFCI or multiple GFCI's for safety. If the ground and neutral share the bus bar in the main panel which is typical, it indicates that the equipment ground and neutral wires are not connected anywhere else if it's correctly wired. The white wire is connected to the ground at the meter box. The ground wire may also be connected to the ground rod. The ground wire in the meter box grounds the meter box housing. I think that different jurisdictions have different regulations on whether the grounding electrode system and ground rod is terminated from the main panel or the meter base. That's my understanding, and I hope this helps.
    1
  15.  @ShyRage1  Are the circuit wires behind the wall running in metal conduit?
    1
  16.  @ShyRage1  okay, I got it now, good job, thanks.
    1