Splitting A Feeder For Two Structures

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?
      

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
      

Hello All,



I'm a DIY'er for most things except things that I want perfectly done and I know my limits. My brother is a licensed Master electrician but has really only dealt with Commercial last several years - his company are commercial electricians who setup new building contruction etc..

Anyway, my wife and I are getting Central Air from our tax money this year. That project starts in two weeks. My brother is going to tie everything together for me (electrical) but I had to do the research and buy everything. The HVAC installer said I need a 30A 2P GFI breaker to a 30A disconnect on the side of my house. I have the breaker specific to my panel, 10-2 wire and PVC conduit, etc.



Question:

I did purchase a 30A fusible pull-out disconnect box and 2x 30A NOS type H fuses. Will this work? The condenser is a new Trane XB13 and I can't find any documentation stating it needs fusible over non-fusible.



Thanks,

~S
      

Is it ok (up to code) to connect 2" rigid conduit to the breaker box using this type of hub  menards.com/main/electrical/rough-electrical/metal-conduit-fittings/2-water-tight-hub-insulated/p-1442092-c-9538.htm  ??



The conduit will exit the panel at the top, go up about 6", then to an LR, then out to the meter about 6' away.  The 6' run will be supported.



Thanks.
      

Just curious which is the prefered way to get the electrical cable through the conduit, and why? 



I see some pull a rope through as they glue the conduit and pull the wire when done.



Others feed the cable through each individual piece of conduit as they go along. 



Thanks in advance for your answers.
      

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
      

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)?
      

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
      

I have a grounding question.  I am installing 400a service to my new home.  We ran 350MCM wire underground thru 3" conduit from the 2ndary terminal (moped) to the house into a 320A Cooper B-Line meter.  From the meter we ran 2 sets of 4/0-4/0-2/0 thru the wall to 2-200a breaker panels ("standard practice", according to my electrical supplier).  The ground wire (#4Cu bare) from the grounding rods comes up from the ground and we're curious if there has to be a special splice connecting the ground wire to each breaker panel or can we run thru one breaker panel to then next, say by connecting the ground wire to a ground bus on one panel and running that thru to the next with #4Cu bare or #6Cu in conductor.  Different electricians are suggesting different methods and the electrical inspector is unsure, but seems to be leaning towards the "special splice". Any feedback would be appreciated.
      

First off im in So Cal. and a few months back my pool equipment stoped working after a rain storm. I have an underground conection that is accseible through a plastic box in the concrete. There is a water proof box there that housed the wiring as it runs from 220 breaker underground to the pool equip., I opened it to find it full of water. The short burned the wiring some where under some 60 feet of cement. I forgot to mention the wiring in existing conduit will not pull through have tried several times even as despreate as a come-along.



Ive had an electrician and Genral contractor both look at it and both said wiring is fried, but im looking for advice on my two options.



1st is cutting a trench in the cement about 60 to 70 feet from circuit breaker to pool equipment. Then using conduit the whole lenght like it was previously but no under ground box. Just two connections breacker & pool Equip.



2nd option the breaker is near my atic. run power from breaker through the house atic to where pops out on the other side of the house. would be about 50 feet through atic and about another 50 feet of conduit 25 above ground attached to eves and 25 below ground to pool equipment. This is a similar route as the gas line to pool equipment they will come out of atic about 20 feet apart then eventually follow similar path is this a problem?? I was told to use 12-3 Romex?? Suggestions on which route to take would be great. Atic is clearly easyer but concerend with closeness to gas line. Thanks before hand for the help