When "existing installation" becomes not

[jxofaltrds]

My understanding is when you change from hardwired and install an outlet for cord and plug, you are “modifying“ the circuit, thereby the need to bring it to code.

You are adding a disconnect means (outlet and receptacle), not modifying the circuit. I would require it. No hardwire for a new appliance in this case.

 

[jap]

I have run into mobile home before with bad neutral in the feeder, and they had different items throughout the house burn out when they happened to unplug their dryer - neutral to frame bond in dryer (that should have been removed when installed) was carrying the neutral for the whole house in that situation and they opened it when unplugging the dryer.

Explain that one more time.

How was the dryer's neutral to frame bond carrying all of the neutral current for the whole house when the neutral conductor from the house panel to the service point was compromised to begin with?


JAP>

 

[ptonsparky]

Explain that one more time.

How was the dryer's neutral to frame bond carrying all of the neutral current for the whole house when the neutral conductor from the house panel to the service point was compromised to begin with?


JAP>

Mobile home. 4 wire to home. EG & neutral bonded at the the SE. Neutral at mobile home panel was compromised, not at the SE.

 

[LarryFine]

Explain that one more time.

How was the dryer's neutral to frame bond carrying all of the neutral current for the whole house when the neutral conductor from the house panel to the service point was compromised to begin with?

Two things had to have happened:

1. The service neutral was broken after the main disconnect, but the EGC was still intact.

2. The dryer neutral and the dryer EGC were mistakenly tied together by the installer.

Thus, the neutral current was flowing from the neutral bus to the dryer neutral, through the above-mentioned connection in the dryer, back on the dryer EGC to the service, where it was bonded to the neutral on the supply side of the neutral break.

It's similar to a broken neutral causing a neighborhood metal water-piping system to carry neutral current to the neighbors' still-intact neutral through everyone's water-pipe bonding. That's largely why the water-pipe GEC is sized for the service.

Had the incorrectly-made connection never happened, the typical lost-neutral imbalance issues would have arisen when the neutral problem first occurred.

 

[Twoskinsoneman]

Thanks all. It's about what I expected as far as a consensus but it's always nice to hear your opinions.

 

[kwired]

Explain that one more time.

How was the dryer's neutral to frame bond carrying all of the neutral current for the whole house when the neutral conductor from the house panel to the service point was compromised to begin with?


JAP>

N & G are (incorrectly) parallel to one another, if one is interrupted the other ends up carrying all the current. In this case neutral current from other branch circuits returns to the panel, has no where to go because of the bad feeder neutral, follows dryer neutral to the dryer through the bonding screw in the dryer then and from there back to the service neutral via EGC's

 

[ptonsparky]

Thanks all. It's about what I expected as far as a consensus but it's always nice to hear your opinions.

We are, if nothing else, consistent.

 

[jap]

N & G are (incorrectly) parallel to one another, if one is interrupted the other ends up carrying all the current. In this case neutral current from other branch circuits returns to the panel, has no where to go because of the bad feeder neutral, follows dryer neutral to the dryer through the bonding screw in the dryer then and from there back to the service neutral via EGC's

I see.

That makes sense.

JAP>