Electrical Discovery... Need suggestions moving forward

[Bradley J Jones]

So.... A couple years ago I bought my first house. After 3 years and 7 offers/contracts on other houses, I found the one that checked nearly every box that the wife and I had. I acquired an 18x21 shop, and the wife acquired a 11x20 amish built log cabin to turn into her sewing studio, which she turned down and took over the attached 2 car garage for.

Anyway, I was under the house a couple weeks ago rewiring a new modem/router location and putting in a couple hardwired LAN connections and did some more in depth scouting. I discovered that my cabin has full 100amp service coming off the house panel, and my shop, which looks to have a 100amp panel, is actually supplied by a 30amp breaker off the main house panel.

Screen grabs of the google view of the house and a crude sketch how the current wiring is laid out...
350125 350127

First picture is the shop panel and the second is the cabin panel...
350128 350129

I'm trying to figure out how to rectify the situation.

My first idea is to just run new 100amp service to the panel in the shop, and downgrade the service to the cabin to maybe 50? My shop needs a whole lot more than what a 30 amp circuit can provide and I'm convinced that 2- 20amp circuits can handle anything that I do with the cabin.

Any thoughts or suggestions other than what I am thinking??

[Larry Frank]

My wife had a sewing room built as an addition. The builder suggested significantly more circuits than what you are thinking. We needed a a 220 for the heat and air conditioning. One circuit for a lot of lights, several circuits for things like an iron or two, and separate circuits for sewing and embroidery machines.

[roger wiegand]

Upgrade the shop, but why downgrade the cabin? The excess capacity there won't hurt anything.

[Mike Cutler]

Run the new service to the shop, and leave the cabin alone.
If the cabin considered an occupied building? Septic, running water and heat,the 100 amp service may have been the minimum code requirement for the building at that time.

[Bernie May]

I have no idea what is going on in that shop panel. From your description it sounds like there is a 30A breaker in your house panel feeding this subpanel, which I assume is connected to that 100A breaker. What is that 100A breaker doing/protecting? Also whomever wired this box did not provide any abrasion resistance for the wires coming into the box.

[John K Jordan]

Run the new service to the shop, and leave the cabin alone.

I agree with Mike - the 100 amps to the cabin shouldn't hurt a thing. In fact, since your wife moved her sewing into the garage it sounds like the cabin might make a good "temporary" auxiliary shop. Just sayin...

I built a stand-alone shop with a 100 amp service. I have two suggestions: if you put in a new breaker box get one with more spaces than you think you will need. I installed one with 20 spaces and mine are full now. Of course I use my shop for wood, welding, machining and more plus I installed HVAC, but any extra capacity in the box doesn't hurt a thing and in the big picture costs almost nothing extra.

Second, I suggest doing careful wire size calculations yourself and then perhaps going to the next larger size wire. My shop is down the hill by my barn, 250 ft from the meter. I got advice on wire size from several professionals but when I did the calculations myself the voltage drop at full load was unacceptable to me. I've been in several shops where lights dimmed when big motors turn on and I didn't want that. I ended up installing larger copper than the others suggested and see no issues today even when the heat pump is running and the 5hp motors on the air compressor and DC cut on at the same time.

You didn't mention whether your existing lines are on poles or underground. If possible, perhaps consider running undergound to avoid issues with storms and lightning and such. Looks better too! All of the wiring on our farm is underground, even the 7200v line to our transformer.

When running wires to the shop, I also included a couple of ethernet cables. It is nice to have ethernet for a security surveillance system and solid WiFi in the shop. I put a spare 2" conduit in the trench too, empty except for a rope in case of future need.

JKJ

[William Payer]

The 100 amp breaker on the shop panel serves only as a power disconnect. The 30 amp breaker in the home panel is protecting the wiring to the panel itself. ( You actually need a main breaker in the shop panel to turn off power to the entire panel from the shop location)

+1 about the lack of bushings for wire entry holes in shop panel. Also, if the sub panel has capacity for more than 6 breaker "throws" i believe it needs a main breaker as a shut off of power to entire panel.

Cabin panel--looks like ground bar is either not connected to exteroir ground rods or the one bare copper wire leading out of the panel looks quite small ( is it sized according to the feeder wires?)

[lee cox]

I am no expert but it sounds like PO cheaped out by running 10 gauge wire to your shop. If you want to up the breaker size you need to run bigger wire to your shop.

[Jim Becker]

Run the new service to the shop, and leave the cabin alone.

I'll also agree with this. Since you have a 100amp panel in the shop, run a new appropriately sized service cable to the shop so you can take full advantage of it and don't worry about the cabin. It's likely equipped as it is for a reason. That shop panel needs to be cleaned up, big-time, however. The cabin panel was clearly done professionally by whomever, but the shop panel is pretty hacked. ;) Of course, that breaker at the bottom of the cabin panel shouldn't be there since it looks unused and has no circuit attached to it. Not a good way to store a breaker...

[Marion Smith]

Is it just me?, or the camera angle?, Or, in the cabin panel, is that a double pole 30A breaker on the bottom LH side with one pole hanging off the bottom of the buss not connected? I agree with previous replies that the panels aren't correct and or need work. My Subpanel in my non-attached shop required separate neutral and ground. Plus, if something goes wrong (emergency)in the cabin, or you just need to kill power to do any work, you'd have to go all the way back to the house main panel to shut off the power! Looking at the corners cut in the shop panel pic, I wouldn't assume anything is correct about that wire run from your house to that panel. Be safe, make it better!!

[Steve Peterson]

Is it just me?, or the camera angle?, Or, in the cabin panel, is that a double pole 30A breaker on the bottom LH side with one pole hanging off the bottom of the buss not connected? I agree with previous replies that the panels aren't correct and or need work. My Subpanel in my non-attached shop required separate neutral and ground. Plus, if something goes wrong (emergency)in the cabin, or you just need to kill power to do any work, you'd have to go all the way back to the house main panel to shut off the power! Looking at the corners cut in the shop panel pic, I wouldn't assume anything is correct about that wire run from your house to that panel. Be safe, make it better!!

I agree that the wiring to the shop panel looks very sketchy. There are way too many issues to trust that the previous owner did it safely. You can tell that it was not wired by an electrician, so I assume the previous owner did it himself.

It looks like the shop panel feeds with NM wiring and not direct burial wires. Any chance that he put it in conduit? Would you be able to string larger wires without digging another ditch?

Steve

[Bradley J Jones]

Run the new service to the shop, and leave the cabin alone.
If the cabin considered an occupied building? Septic, running water and heat,the 100 amp service may have been the minimum code requirement for the building at that time.

I'm not really sure what the deal was there. Going through HVAC warranty paperwork this summer to get a repair done, I found the receipt for the cabin purchase/transport/install including wiring. It is unoccupied, as the PO used to have some HAM radio equipment in there along with storage. No water or septic either.


I agree with Mike - the 100 amps to the cabin shouldn't hurt a thing. In fact, since your wife moved her sewing into the garage it sounds like the cabin might make a good "temporary" auxiliary shop. Just sayin...

I built a stand-alone shop with a 100 amp service. I have two suggestions: if you put in a new breaker box get one with more spaces than you think you will need. I installed one with 20 spaces and mine are full now. Of course I use my shop for wood, welding, machining and more plus I installed HVAC, but any extra capacity in the box doesn't hurt a thing and in the big picture costs almost nothing extra.

Second, I suggest doing careful wire size calculations yourself and then perhaps going to the next larger size wire. My shop is down the hill by my barn, 250 ft from the meter. I got advice on wire size from several professionals but when I did the calculations myself the voltage drop at full load was unacceptable to me. I've been in several shops where lights dimmed when big motors turn on and I didn't want that. I ended up installing larger copper than the others suggested and see no issues today even when the heat pump is running and the 5hp motors on the air compressor and DC cut on at the same time.

You didn't mention whether your existing lines are on poles or underground. If possible, perhaps consider running undergound to avoid issues with storms and lightning and such. Looks better too! All of the wiring on our farm is underground, even the 7200v line to our transformer.

When running wires to the shop, I also included a couple of ethernet cables. It is nice to have ethernet for a security surveillance system and solid WiFi in the shop. I put a spare 2" conduit in the trench too, empty except for a rope in case of future need.

JKJ

All existing wiring is underground. The shop is in 3/4" PVC conduit that is, in some places, ON the ground next to the concrete driveway. Another reason to just do away with it and rerun new good service.

I do have 2 bandsaws and a TS, that are 3 phase, the TS is actually getting a restoration with a 1ph motor, but a couple 220 circuits are an absolute necessity, especially if I want to upgrade to a real DC system rather than a shop-vac cyclone setup.



I have no idea what is going on in that shop panel. From your description it sounds like there is a 30A breaker in your house panel feeding this subpanel, which I assume is connected to that 100A breaker. What is that 100A breaker doing/protecting? Also whomever wired this box did not provide any abrasion resistance for the wires coming into the box.

I'm actually quite ashamed of myself for not discovering things like this sooner. I'm usually very good at researching and inspecting before I buy but I will chock it up to my first house purchase and a learning experience. The lack of bushing was one of the first things I saw when I opened the panel to take pictures.


The 100 amp breaker on the shop panel serves only as a power disconnect. The 30 amp breaker in the home panel is protecting the wiring to the panel itself. ( You actually need a main breaker in the shop panel to turn off power to the entire panel from the shop location)

+1 about the lack of bushings for wire entry holes in shop panel. Also, if the sub panel has capacity for more than 6 breaker "throws" i believe it needs a main breaker as a shut off of power to entire panel.

Cabin panel--looks like ground bar is either not connected to exterior ground rods or the one bare copper wire leading out of the panel looks quite small ( is it sized according to the feeder wires?)

I also noticed that the ground bar is significantly smaller gauge that the one in the shop as well. I guess Ill be upgrading that during this little adventure too.


Is it just me?, or the camera angle?, Or, in the cabin panel, is that a double pole 30A breaker on the bottom LH side with one pole hanging off the bottom of the buss not connected? I agree with previous replies that the panels aren't correct and or need work. My Subpanel in my non-attached shop required separate neutral and ground. Plus, if something goes wrong (emergency)in the cabin, or you just need to kill power to do any work, you'd have to go all the way back to the house main panel to shut off the power! Looking at the corners cut in the shop panel pic, I wouldn't assume anything is correct about that wire run from your house to that panel. Be safe, make it better!!

Yes, the cabin does have that extra 30amp on the bottom just sitting there. Actually, the cabin panel only has the top 2 on each side breakers actually hooked up to anything, which is a little crazy because they are all supplying one outlet a piece - 3 interior and 1 GFCI exterior one. Do I need to upgrade the breaker itself for the exterior one or is the outlet itself sufficient?


I agree that the wiring to the shop panel looks very sketchy. There are way too many issues to trust that the previous owner did it safely. You can tell that it was not wired by an electrician, so I assume the previous owner did it himself.

It looks like the shop panel feeds with NM wiring and not direct burial wires. Any chance that he put it in conduit? Would you be able to string larger wires without digging another ditch?

Steve

It is in conduit, that is mostly ON TOP of the ground running next to the concrete driveway, which will make it easy to remove, but unable to use for larger wires.


After reading your replies, which I am very grateful of, I think n I might be investing in new 100amp service for the shop. I really want to run a few home run shots of the CAT5E that I have as well so I'm not relying on WIFI that far out anyway.