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Discussion Starter · #1 ·
100A disconnect at the group meter pedestal for this 100A service panel in this mobile home. Two extra DP 240v circuits connect to the 100A main breaker and feed two subpanels per below:

Black cable exiting panel top feeds 50A subpanel for an older air-conditioning package unit. White cable returns from that subpanel, connects to package unit.

Cable exiting just above neutral bus bar feeds another subpanel for electric kitchen range.
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Black cable exiting far left of panel top connects to dryer DP 30A breaker at top of right bank.

DP 20A breaker is for water heater.

All red switches are 20A I believe, and the others are 15A.
 

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Discussion Starter · #3 · (Edited)
Do you have a question or are you trying to correct a mess?
I'm just guessing the subpanels are not wired correctly and that there shouldn't be two extra 240v cables jammed into the top of the main breaker. That's all I'm really interested in. I won't be working on it. Just want to inform the owner why they're not set up correctly. Would like to tell them how to correct the mess.

You look really comfy in that big ol' easy chair.
 

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The main breaker should only have one set of wires in it.

I don't see grounding in the small disconnect and they are missing cable connectors.
 

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Looks like a disconnect for an air conditioner on a MH. If so, there shouldn't be a neutral, just a ground.
 

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Discussion Starter · #9 · (Edited)
You are quite correct !

Depending on the size of the load
from the sub panels, you could feed them
thru breakers off the existing panel.
How many spare slots ?
it looks like only one ?
Wouldn't bet my life on it, but don't remember there being any more empty slots, but maybe you're saying 'it looks like there's only one' because the number of slots is always balanced (same number of slots on both right and left bank)? Haven't measured the package unit amp draw yet, but my experience in this park is usual load of 11-15A on similar units. Just had a 29-yr. old package unit amp draw of 15+ amps. Data plate RLA amps was 17.9

The other subpanel (no pic) feeds an older coil burner kitchen range.
 

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Discussion Starter · #10 · (Edited)
Looks like a disconnect for an air conditioner on a MH. If so, there shouldn't be a neutral, just a ground.
It is for an air-conditioner/mobile home, and I assume you're saying "there shouldn't be a neutral" because it just isn't needed.

This subpanel/disconnect (pic) is indeed for the package unit. Since there is no grounding in this pic, the package unit cabinet is not grounded, correct? Once had a compressor wire fall off its comp. terminal while running. Hit the cabinet and kicked breaker off. If that cabinet had not been grounded, and wire remained in contact with the cabinet, not a good situation I'm thinking, yepper?... just like this ungrounded cabinet situation maybe.

What are the possible consequences of the extra two 240v circuits jammed into the main breaker top?
 

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Discussion Starter · #11 · (Edited)
It is for an air-conditioner/mobile home, and I assume you're saying "there shouldn't be a neutral" because it just isn't needed.

This subpanel/disconnect (pic) is indeed for the package unit. Since there is no grounding in this pic, the package unit cabinet is not grounded, correct? Once had a compressor wire fall off its comp. terminal while running. Hit the cabinet and kicked breaker off. If that cabinet had not been grounded, and wire remained in contact with the cabinet, not a good situation I'm thinking, yepper?... just like this ungrounded cabinet situation maybe.

What are the possible consequences of the extra two 240v circuits jammed into the main breaker top?
Tried to edit my post #10, but edit time expired, so editing here. The neutral white wire leaving the subpanel would be connected to the package unit cabinet, but the neutral (used as a ground wire) should've been connected to a ground bus bar mounted to the subpanel box, correct?

This box is not really a subpanel box, because it's too small (no room/place for a mounting a ground bar, yes?
 

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The white for most AC units is the second hot leg to the 240 volt unit.
 

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Green tape should be put on the white wire on both ends. And connected to the ground bar in the main panel. And the package unit grounded by it.

A package unit that is not grounded. Can electrocute you if a line wire were to short to the package unit case/frame. Or if the compressor or condenser fan motor windings short to frame.

There have been a couple HVAC techs killed that way.
 

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Discussion Starter · #14 · (Edited)
Green tape should be put on the white wire on both ends. And connected to the ground bar in the main panel. .... because the neutral bar might be too busy with normal operation of branch circuits, and the ground circuits will not be... correct? This is the same reasoning behind the change from 3-wire dryer cables to 4-wire, correct?

A package unit that is not grounded. Can electrocute you if a line wire were to short to the package unit case/frame. Or if the compressor or condenser fan motor windings short to frame.

There have been a couple HVAC techs killed that way.
Good to know, but not good to hear! I'm getting into the habit of using a non-contact voltage detector when walking up to a cabinet (Yuri pointed out this risk a while back). You have a better way?

What causes a motor winding to short to the motor frame? Besides age and overheating?

What are the possible consequences of the extra two 240v circuits jammed into the main breaker?
 

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Good to know, but not good to hear! I'm getting into the habit of using a non-contact voltage detector when walking up to a cabinet. You have a better way?

Thats about the best way to see if its safe to touch a unit.

What causes a motor winding to short to the motor frame? Besides age and overheating?

Thats about it. A weak cap can cause a motor to run hot.

What are the possible consequences of the extra two 240v circuits jammed into the main breaker?
Depends on the actual service size. I'll let the electricians go into a better explanation then that.
 
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The lugs are made for one wire. Stuffing multiple conductors in the lug can lead to over-tightening, hot spots or loose connections. All of these can lead to issues including fires.
 

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Discussion Starter · #17 · (Edited)
The lugs are made for one wire. Stuffing multiple conductors in the lug can lead to over-tightening, hot spots or loose connections. All of these can lead to issues including fires.
Issues like over-amping circuits/damaging equipment?

If we move the white wire (serving as ground for the package unit cabinet) from the neutral bar in the panel, over to the ground bar in the panel, is it acceptable to pigtail it (it's too short) using a wire nut?

I assume moving it to the ground bar is better, because the neutral bar could be too busy with normal branch circuit activity, which is probably the same reason dryer circuits went from 3-wire to 4-wire. Yepper?
 

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Good to know, but not good to hear! I'm getting into the habit of using a non-contact voltage detector when walking up to a cabinet (Yuri pointed out this risk a while back). You have a better way?

What causes a motor winding to short to the motor frame? Besides age and overheating?

What are the possible consequences of the extra two 240v circuits jammed into the main breaker?
1 - The enamel insulation on the coils can breakdown causing shorts to frame, this can be made worse by enviroment conditions.

2 - Most likely the chance of the connection of both wires to the terminal may not be as good as it should be.
 
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