Broken Feeder Cable?

Garage running Underground feeder 4/4/4 AL from main panel off dual 80 amp breaker.

Yesterday I found half the garage panel was inoperative.

Tested lugs, one of the feeders is 120V, the other is at 80-90V.

Swapped the feeders at the 80 amp main to ensure it wasn't the breaker. Same results.

Tested at the 80 amp breaker at main panel, both legs 120V.

When I remove the 80-90V feeder off the 80 amp main panel breaker and test it at the garage it drops from 80-90 to 0.



No breakers trip. Is this one feeder line broken underground or split open and grounded to earth?
      


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Need a little advice... Here's the scenario:



-200 amp meter/main.

-2 small side by side residences with 80 amp load each.

-Each residence has a 200 amp panel with main disconnect.

-1 3" conduit from meter to underground pull box between both buildings

-A 2" conduit from the pull box to each building.

-All conductors to be 3/0



Is there any reason why a 3/0 feeder with ground could not be pulled to the

pull box and then split to run to each building instead of running 2 separate 100 amp feeders? Any other things to consider?
      
I am replacing a feed through breaker panel the bus bar and breaker was inverted but the main breaker is up and down with on being down and I also noticed that the plastic in the back that holds the bus bar is cracked.



I bought a newer model from the same manufacture that has a much better design and a better main breaker.  But unlike the one I already have when you invert it the breaker slots don't line up and cover does not fit properly.



I was thinking about just cutting out the center where the breaker slots are.  I measured and if I cut it just right all I have to do is turn it over and it will line up just have to bolt or weld it in place.  Would this be legal



I also thought about putting the panel the way it came and feeding the bus bar hot and keeping the panel under the 6 throw rule.  Or would that not work because I am using feed through.  There will be 4 double pole breakers and the one main that feeds a sub panel.





I really hate the cheap design of this panel.







I plan to replace it with this.




      
My existing service entrance consists of an external Meter can mounted on the outside of the garage wall directly behind a SD Main Breaker Panel (MBP) with a 150 amp main breaker.  In order to support upgrades, I am installing a second MBP (200 amp) inside the garage in the wall cavity right next to the existing panel.



Local code requires that the upgraded Meter can be purchased from the City Utility.  I have already confirmed with the local inspector that either 4/0 Al or 2/0 Cu SE cable are acceptable for both the existing and new MBP.



My question is what is the code requirement for getting the 3 SE cables run from the dual lugs to the new panel?  Can those conductors run into the same wall cavity where the existing panel is installed?  If so, I'm certain they can't go through the same conduit nipple that connects the back of the meter can to the existing MBP.  Can they route in behind/above/below the existing panel and through a hole in the wall stud to gain access to the adjacent stud bay to get to the new panel?  If not, do they need to be routed out of the meter can on the external wall in conduit over to the next stud bay and then enter the wall there to gain access to the new panel?  If external conduit is required I would expect it must be metallic as opposed to PVC.



Best Regards,



Ted
      
Hi guys. I'm Dan, and I'm in Knoxville, TN. I know running power to a shed is a very common topic here. I've been doing tons of reading and feel pretty comfortable with the requirements, but I have two questions I haven't been able to find a clear answer to.



First, my situation: I'm having a 10x16 shed built in my backyard, to be used primarily as a woodshop. I need more than a single circuit, so I know I need a subpanel and two grounding rods at least 6' apart, bonded to the subpanel with #6 bare copper wire.



My house has 200 amp service, and the main panel is in the garage at the opposite corner of the house from where the shed will go, so it would be pretty inconvenient to run a feeder from, there. But there's an existing 100 amp subpanel in the basement, presumably installed when the previous owner finished the basement. I'll be running a 60 amp feeder from that subpanel to the shed.



My total run will be something like 75', so I'm running #6 THWN for the two hots and neutral, and #10 THWN for the ground. I plan to bury it in 1.25" schedule 40 PVC, buried 18" deep.



My first question relates to how I need to run the wire when it's not underground. The basement is finished with a drop ceiling, so I plan to run the feeder across the drop ceiling, out of the house, down to the ground (it's a walk-out basement), then underground the 26' to the shed. I assume it still needs to be in conduit for at least the part that runs up the wall of the house. But what about inside, when it runs through the drop ceiling to the panel? Does it need to be in conduit for the whole run? Or would I just staple the four wires to the joists or something?



The other question relates to the trench. I've got a rain gutter downspout that discharges right at where the shed will soon be, so I'm running a 40' length of 4" PVC to pipe that water past the shed. It will be buried just about 6-12", just enough to run under the shed. Can I run the power conduit in the same trench (obviously, deeper)? Presumably I'd dig the 18" trench to the shed, lay the schedule 40, then add a few inches of dirt to bring it up to about 12" deep, and extend the trench past the shed at that depth, then lay the 4" drain pipe and backfill. Or do I need to dig two separate trenches? Is there a rule about how far apart they need to be if so?



If anyone sees any other flaws or concerns with my plan, please do speak up, I want to do this right. Thanks!



Dan
      
I built a free standing garage with main power tapped from the home breaker box.  The contractor pulled 4 wires via a conduit to the freestanding garage panel which supplies lights, a garage door, and two 20 amp outlets.



Everything worked well initially, but about 1 week ago one section of the lights in the building went out.  The contractor came out and found that one of the two hot wires in the garage panel was only seeing 100 volts and that went down if anything else was turned on.  He swapped one of the ground wires for the bad hot wire and everything now works. 



What would cause a situation like this where the hot wire apparently had a voltage loss?  Is it safe to continue with the fix where the faulty wire is now the ground?



Thanks in advance!
      
I'm having quite the time finding an electrician who will quote this.  Just about all of them say that what I need is to upgrade my main panel but I want to install a new main panel that is a part of the meter base outside and make my current 100A panel a sub.   Maybe you people can tell me why nobody seems to want to do this.  Here are a few shots of the existing meter (note what is apparently a 60A base here)






and a shot of the conduit headed underground.  Like most homes built during this era, the conduit makes a right turn underground to enter through the cinderblock, ending up coming into the back of the main panel.  This conduit encloses a 4 wire feed. edit: no, actually it is only a 3 wire feed which is a problem if I want to convert the original main panel a sub.






Here's the existing panel.  It's a 60's era Square-D split panel with a 30 amp sub panel for the finished basement.  Those are low voltage wires to circuit taps for my home energy monitoring system btw.






The reason I don't want to upgrade this panel are as follows:

We won't be expanding the electrical west of this panel any more.  All planned expansion (240v car charger in Garage, planned 3 season room with grid tie Solar on the roof) will be to the east.


Upgrading the panel will require major surgery to the walls.  Due to the way the original basement is engineered there, the walls have an intricate stud pattern behind the existing panel.  I'd pretty much have to rip out a 4' section and redo it to make the access large enough to handle a 200A panel.


Adding additional circuits to an upgraded panel will require an act of God due to the finished basement construction.  There are no raceways for additional circuits.






Based on this, my thoughts were to create a new 200A main panel outside based on something like the GE model TSM420CSCUP loadcenter.  Here's a shot of this panel:






This particular panel has room for three 2-pole breakers in addition to the 200A mains.  I'd add a 100A 2-pole breaker for the existing panel, with the other two reserved for the garage/solar expansions.



The issue with the contractors who have quoted the job appears to be the conduit going to the existing panel.  I'm not sure what's wrong with it but it is apparently not compliant with current code.  Obviously the bonding needs to change, new grounding electrodes need to be driven, and a water pipe ground needs to be established to the new main panel, but what else is required?



I'd like to throughly research all the code considerations here so I can approach a contractor from a more knowledgable perspective then determine the best way to perform this upgrade.  Due to POCO coordination and the need to cut household power for the duration of the job, I have no desire to DIY this one...



So what exactly is wrong with the conduit running from the existing meter base to the existing load center?  Why is everybody telling me that I can't do essentially what I've described above?  What are the relevant code sections that will apply to this job?  Should I be chatting with my AHJ about local considerations now or should I wait until I have the code requirements down pat (assuming the latter here)?
      
I have a small 19 gallon water heater in a small garage space, that was installed by some questionable handymen a few months back.  I just had the plumbing and septic finished so tested the hot water, only to find the element was already burned out.



I noticed however, that this 120v unit is wired via 10 gauge wire to a 30 amp double breaker.  This is questionable because I thought a 120v appliance would be wired to a single pole on the hot wire and run neutral to the neural panel area.



My question is, can I run the hot wire out of one side of the double breaker without safety issues, or should I definitely replace it with a single pole breaker?



I would normally not question the work, but everything these guys did already had to be adjusted, so I'm only naturally assuming this may need to be also.



If its safe, I would like to simply things and just connect the one hot and leave an open space in the other half of the double pole... Is this possible?



Thanks for your advice-
      
In a large bunkhouse we need to add a second range, water heater, and kitchen outlets.  The existing panel is 125 AMP (with breaker), and don't want to redo entire panel.  A consultant said to install a 200 AMP drop, with a panel to handle the additional load.  Would you then feed each of the panels from that drop as main panels, or use a new 200 AMP panel as the main, and the 125 as a sub-panel from that?  I assume in either instance, the grounding would be done as a 200 AMP service.  Just realized if each was a main panel, the new one couldn't exceed 75 Amps, or total would be over 200.  Any other ideas appreciated.
      
Greetings,



I am looking to wire a sub-panel in my barn to support a general workshop.  Loads would include standard woodworking tools (including 220V table saw), welding, air compressor, etc.



The house has 200AMP main breaker and minimal in-house loads.  Dryer is gas, Oven and cooktop are gas.  Water heater is off the oil furnace.  I think the biggest single load is the well-pump and/or fridge compressor.  We do have sporadic toaster oven, hairdryers etc.  Otherwise its just lights, ceiling fans, flat-panel tv, stereo...



We had 4" conduit installed to the barn, so there is plenty of room to pull a big cable.  The entire run from the house panel to the barn totals around 155' (probably less, but rounding up)



My questions a



Can I pull a 100AMP sub-panel from my main house panel as described?


Would 4/0,4/0,4/0,2/0 aluminum service entrance cable be a good choice for this run?  Could I do it with something lighter?


Could I put an additional sub-panel in the garage (about halfway to the barn) by interrupting the run?  The garage subpanel would have a 220V plug for possible welding and/or electric car charging.  Would this require a separate run?


Are there any other considerations I should be thinking about in planning this?




Thanks for any thoughts you can share on this! 



Cheers,



pete
      
Hey guys,

we have a 4-plex in San Diego that we bought several months ago that was built in 1950. According to inspector's report, we needed electrical upgrades. One of the electricians told us city is under a project to underground all the electrical lines, and if we do not do upgrades the way city EXPECTS us, once our neighborhood is due for undergounding, we will have to REDO the whole thing again (like changing the location of the MAIN electrical panel from where it is now).

Can they FORCE these upgrades to the owners? I am talking about a 15000-20000$ that will be required... It is not cheap...



What we wanted to do is the very minimum, but to make sure our tenants are safe: just replace fuses in each unit with BREAKERS and leave it in the closets as we "grandfathered" them in and replace the main panel fuse with a breaker.

But according to the advise of an electrician based on the city undergrounding requirements, we will have to RELOCATE the fuses from closets to the OUTSIDE of the building AND RELOCATE the main panel from where it is now to an opposite direction (closer to the main street).

Can the city ENFORCE us to do this?