125Amp Sub Panel (electrical help-me)

[Avadon]

So I'm looking at this house and I believed it to just have a 200 amp service. I thought I'd just have to run my electricity to the shop from the 200 amp service and just share the house with the 200amp. I did this in massachusetts. Never had a problem, never dimmed lights or anything like that. 200amps is heck of a lot of power. I could run the dryer, washer, 30amp industrial compressor, and 30 amp welder all while having tv+lights, etc running and never had even the slightest issue. I think the range/oven was probably even running during one of those times. They probably never draw their full amount except for start up. So I might not have been anywhere near capacity.

Anyway this house has a 200 amp service AND a 125amp sub panel in the garage. Is this a better setup than running off the 200amp service?

I am just wondering if 125amp will be enough. I have a 30 amp compressor, 30amp tig welder, misc power tools, shop lights. I'm guessing I'll be okay? Does anyone here have a 125 service in their shop and can testify to them?

When they ran some of the outlets and lights they just laid the wire ontop of the rafters. This isn't to code is it? I've always run down boards or even put boards in to secure the conduit. I mean it looks like garbage to boot and it kills your ability to throw light storage up there without interfering with electrical. What is the best way to shore those up. Something like a 1" x 5" board screwed to the rafters to act as a highway to neatly secure those lines to. Is there any problem running electrical 15/20amp lines a few inches apart for a long parallel run?

[Avadon]

PS.. no idea what all those breakers are for. I think they just put them in with the idea that there was going to be more electrical because all there is in the garage is the automatic garage door on one door, maybe 6 outlets, and one or two flourescent lights. Almost nothing. I'll probably put in 12-15 outlets, 6-8 eight foot flourescent light fixtures, 3-4 220V 30 amp plugs.

As I'm just one person I wouldn't think I'd ever use more than 100amp by myself. But i'm just not sure what I could have in there in the future. Just out of curiousity can you have a 200 amp sub panel from a 200amp breaker. Basically just a sub-station?

[Avadon]

Oh yah and I should have no problem running single phase 220V 30amp lines off of this (like before) right? I could probably get more pics of the inside of this sub panel down the road.

[edge9001]

you pose some good questions I would need to have some of these answered as well. I hope someone here will be able to help.

[HWHII]

Buy no means am I a electrician, but my dad was a union electrician and I stayed at a Holiday Inn Express last night.

In my house I have a 200 amp main service panel off that I jump a tap I believe 4/0 cable under ground 140 ft. to a 125 amp sub service panel in our smoke house then jump another cable 100 ft to my shop which has a 200 amp sub service pannel in it. We have 2 HVAC units in the house which is 4000 sg. ft. and in the shop I am running 5 230 circuts ranging from 100 amps to 30 and numorus 110. I have never had a proublem. I should also add my friend is a licensed electrician and helped me install this system. He told me as long as you are not running everthing at once you are ok. Just make sure your wire is large enough to carry the load with out a voltage drop and the service pannel has enough circuts to spread your load out.

[ciladog]

So I'm looking at this house and I believed it to just have a 200 amp service. I thought I'd just have to run my electricity to the shop from the 200 amp service and just share the house with the 200amp. I did this in massachusetts. Never had a problem, never dimmed lights or anything like that. 200amps is heck of a lot of power. I could run the dryer, washer, 30amp industrial compressor, and 30 amp welder all while having tv+lights, etc running and never had even the slightest issue. I think the range/oven was probably even running during one of those times. They probably never draw their full amount except for start up. So I might not have been anywhere near capacity.

Anyway this house has a 200 amp service AND a 125amp sub panel in the garage. Is this a better setup than running off the 200amp service?

I am just wondering if 125amp will be enough. I have a 30 amp compressor, 30amp tig welder, misc power tools, shop lights. I'm guessing I'll be okay? Does anyone here have a 125 service in their shop and can testify to them?

When they ran some of the outlets and lights they just laid the wire ontop of the rafters. This isn't to code is it? I've always run down boards or even put boards in to secure the conduit. I mean it looks like garbage to boot and it kills your ability to throw light storage up there without interfering with electrical. What is the best way to shore those up. Something like a 1" x 5" board screwed to the rafters to act as a highway to neatly secure those lines to. Is there any problem running electrical 15/20amp lines a few inches apart for a long parallel run?

A subpanel is just a way of isolating and making it more convent and less expensive to manage circuits. Instead of running 4 or 5 individual circuits from the main house panel to the garage they run one line that can handle 125 amps into a subpanel. From the subpanel, they run the individual circuits. If you trip a breaker in the garage, you don’t have to go to the main house panel to reset.

It is not likely that a house would have a larger service than 200 amps. Just because the subpanel is 125 amps doesn’t mean you will be drawing that from the main panel. It’s a good setup

[Fosterob]

It is cheaper to run 125 amp wire to the garage than 200 amp wire. I would be surprised if you used more than 125 amps. Be thankful someone thought to put some real electrical in the garage for you. Most are lacking to say the least.
Rob

[Avadon]

Yah I was quite surprised to see the sub panel. Mostly because the main panel is literally 8-10 feet from the sub panel. In this house there is a main panel in the mud room and then the sub panel is in the garage, next room over. So they probably just fished a wire over the ceiling of the mud room/laundry room and to the garage. Probably wasn't more than 10' of wire.

If for some reason I do trip the main on that 125amp panel. Is it unreasonable to think that I could fairly inexpensively re-run a heavier guage conduit and make that sub panel a 150, 175 or 200amp service?

[pkrankow]

Yah I was quite surprised to see the sub panel. Mostly because the main panel is literally 8-10 feet from the sub panel. In this house there is a main panel in the mud room and then the sub panel is in the garage, next room over. So they probably just fished a wire over the ceiling of the mud room/laundry room and to the garage. Probably wasn't more than 10' of wire.

If for some reason I do trip the main on that 125amp panel. Is it unreasonable to think that I could fairly inexpensively re-run a heavier guage conduit and make that sub panel a 150, 175 or 200amp service?

If you don't mind doing some drywall work, that would be easy...once the wall is opened up. The panel may need changed as sometimes they lack the capacity to hold the larger wire.

Phil

[don't tread on me]

My dad is a electrishon here in Nebraska some of the codes might be different where you are but I will see what he seas later on when he gets home.

[Avadon]

My dad is a electrishon here in Nebraska some of the codes might be different where you are but I will see what he seas later on when he gets home.

Cool. Thank you, I appreciate reporting back whatever you find.

[Fosterob]

I think you would need a new panel as well as new breaker and new wire. If you do have a need for 200 amps in the garage then you would use a "pass through" rated for 225 amps instead of a breaker to feed your new panel. The main breaker protects everything that way. I am currently running my entire shop of one 50 amp breaker feeding a sub panel. I run a few large welding machines, 5 hp compressor, nazel 2b and marvel #8 bandsaw, a small bandsaw, along with a dozen or so grinders, drills and misc. tools. It never all runs at the same time even with 2 people doing work at the same time. I have never tripped the 50 amp breaker so I am curious what you need so much power at one time for, do you own stock in the utility company? It is common for me to be using both saws and drill press at the same time someone else is welding with the compressor running.
Hope this is helpful to you.
Rob

[Fosterob]

May be that 125 amp is max breaker size for feeding subpanels, that is why I needed the pass through. My current set up is main panel on a pole away from the house with a 200 amp main breaker. It used to have a 100 amp breaker feeding the house. I moved the pole and ran new 200 amp wire to the house with a 225 amp pass through to feed subpannel in the house, it has a 200 amp main breaker in it. When I finish the new shop building the house subpanel will get a 225 amp pas through to fedd another 200 amp panel in the shop. That is going to have 200 amps available at all panels, But here the panels are all spaced far apart. The main comes in by the well and feeds house about 75' away and another 100' further is the shop.
Rob

[dkaschner]

It is actually a pretty good setup. I have a similar setup at home, a 125 amp subpanel sitting next to the main panel in my smithy (walled off the 3rd stall in the garage). The smithy lights, safety alarms (CO, fire and flamable gas detectors) and fan are run off of the main panel. This was done to allow me to hook up all of my equipment to circuits from the subpanel. As a result I can lock-out all of my equipment by flipping the subpanel breaker and locking the subpanel, while still maintaining power for lights, detectors and safety equipment.

I have never tripped the 125 amp breaker. I would guess you shuold be fine with 125 amps.

Dan Kaschner

[Avadon]

It is actually a pretty good setup. I have a similar setup at home, a 125 amp subpanel sitting next to the main panel in my smithy (walled off the 3rd stall in the garage). The smithy lights, safety alarms (CO, fire and flamable gas detectors) and fan are run off of the main panel. This was done to allow me to hook up all of my equipment to circuits from the subpanel. As a result I can lock-out all of my equipment by flipping the subpanel breaker and locking the subpanel, while still maintaining power for lights, detectors and safety equipment.

I have never tripped the 125 amp breaker. I would guess you shuold be fine with 125 amps.

Dan Kaschner

Yah between what you and Rob are saying I'll probably never trip that breaker. For the most part it would be lights, compressor, and welder running at the same time, along with a 220v heater in winter/ air conditioner in summer. I guess if I did start tripping that I would just put in a higher guage wire and breaker and upgrade that sub panel.

In Illinois I did have a 30amp breaker in the garage (it was way old electrical) and it would trip all the time. Had to be vary careful about how many lights and tools I ran.

I guess I can always just try and if need be upgrade the sub panel. Doesn't sound like i'd have to re-run all the outlets/lights if I did change it. Because that would be a lot of work.

Where do you get CO detecters? I have a fire detector that is batter operated that detects carbon monoxide, fire/smoke. One time I cracked the acetylene tank and it wasn't very much but it did set off the smoke alarm. Good to know that thing was working. What detectors do you use for safety?

[arftist]

Consider running your air compressor off the main instead of the subpanel.

[ThomasPowers]

I have two panels for my house, one inside and one mounted outside mirroring the one inside. (House was built in two stages so they added another panel when they build the second half---it's rather excessively wired and insulated as the builder lived in it for a dozen years.

[dablacksmith]

i dont think you will have any problems with this setup anything over 100 amps and i would be real suprised if you ever use that much at one time .. i ran a 30 X 40 shop with compressor power hammer and welder chop saw and 15-20 4 ft double tube floresent lights in it from the same size breaker never had a problem with the main. the chop saw would occasionally pop its 20 amp breaker but never tripped the main. have fun!

[Woodz]

I make my living doing electrical work but bear in mind that opinions vary form one electrician to another and code varies from location to location... With that said I would be surprised if you need to upgrade the 125 for your intended use. If you do start tripping the 125 eliminate the possibility of a weak breaker BEFORE you consider upgrading.

As for your wire runs they may or may not be compliant, depending on your local. Way back when copper was cheap we squared our corners and ran things neatly. These days we mostly run as little wire as possible, running straight from point A to point B which can leave quite a tangle. Doing neat work has given way to keeping the cost down. You are correct in that it is an eyesore as well as sometimes an inconvenience, but in today's cutthroat construction economy...

You shouldn't have a problem bundling wires if they are all carrying line voltage. It can create problems if you include low voltage, phone, or data cables in your bundle. You can build an electrical chase with 3 boards placed like this |_| and re-run your wiring inside for a neat, well protected attic space.

Hope that helps.

[Avadon]

I make my living doing electrical work but bear in mind that opinions vary form one electrician to another and code varies from location to location... With that said I would be surprised if you need to upgrade the 125 for your intended use. If you do start tripping the 125 eliminate the possibility of a weak breaker BEFORE you consider upgrading.

As for your wire runs they may or may not be compliant, depending on your local. Way back when copper was cheap we squared our corners and ran things neatly. These days we mostly run as little wire as possible, running straight from point A to point B which can leave quite a tangle. Doing neat work has given way to keeping the cost down. You are correct in that it is an eyesore as well as sometimes an inconvenience, but in today's cutthroat construction economy...

You shouldn't have a problem bundling wires if they are all carrying line voltage. It can create problems if you include low voltage, phone, or data cables in your bundle. You can build an electrical chase with 3 boards placed like this |_| and re-run your wiring inside for a neat, well protected attic space.

Hope that helps.

Excellent. Thanks for the help. I just got a call from a local electrician too and he confirmed what you said. Good to hear two electricians saying the same consistant thing. I think I'll be fine on the 125amp. Doubt I could ever trip that main even if I turned everything on at once and ran it at full capacity. This local electrician said you'd probably never even come close to capacity.

Thanks for the tip on the wire running. I used to do systems engineering and have run a ton of cat 5, so that's probably where the comm/power running concern got wrapped up in my mind. I like the idea of the electrical chase. That will provide a good protected place for them to lay in.

Thanks all for the help. Excellent responses. Not having to change that panel will save me a huge amount of time. Faster I get up and running the faster I can start making money to pay the mortgage.

[BIGGUNDOCTOR]

Look in the attic space of a lot of homes and you will see Romex run all over the place, and stapled to the rafters.

My Dad's old shop had 125A a subpanel in it. The only thing that I had that could possibly trip it is my 350A Linde TIG welder 99A on 220V-max draw. Welders only pull max when set on maximum settings. Compressors draw the most on start up then drop way off. You would have to be doing some serious work to trip that main.

[Steve Sells]

As a master Electrician in IBEW 305, and former contractor, I have to comment on the twin breakers I see on the photo. While the separate channels can deal with full the rated load on their own, if all of these are being used the total output will be limited, IE a bank of twin 20 amp breakers will not do well if they are all running at 20 amp loads.

We only use those twins when the panel is full and waiting to be upgraded soon, or when rarely used items need individual protection. I would change them out to single breakers, lose the tiwns.

Don't worry about the romex, some areas require conduit many do not, as long as its protected from the abuse and sunlight you are fine.

[dkaschner]

I had the company that did the initial wiring come in and install the CO detector, flamable gas detector and heat detector. They have a 'low-voltage' side to their business that installs a lot of safety equipment for businesses around here. They were great. The guys remembered me, as they don't do a lot of work for blacksmithing / bladesmithing shops. I had an alarm horn and light set up right out side of our back door to the garage so that if anyhting went wrong in the smithy it would be 'intuitively obvious' to anyone in the house.

I decided that a smoke detector would not work well. Heat treating causes a ton of smoke and would always be setting off the alarms. Theflamable gas detector is great. Heck I can't even spray paint in the smithy without proper ventilation without the alarm going off.

Sorry for the long post. Bottom line is that the detectors are not from Home Depot, i.e., I didn't install the safety equipment myself. If you are still interested, I can pull out the manuals and get more information.

Dan

[Avadon]

Sorry to harass... but I have one more question.. the shop is not insulated.. do I need to insulate+drywall the walls before I start doing the electrical? Or can I just run down the walls and make my outlets?

I do want to insulate and sound proof at some point and i'm hoping I can just put that behind the electrical?

I am on the fence about whether I want to dry wall or not. Is this reccomended? Do I have a fire hazard not covering the insulation? I like the open studs simply because it's easy to see them, bolt to them, hang something off them, drive a nail, etc.

Ideas here would be great.. Thanks in advance for all the help.

[Avadon]

As a master Electrician in IBEW 305, and former contractor, I have to comment on the twin breakers I see on the photo. while the separate channels can deal with full the rated load on their own, if all of these are being used the total output will be limited, IE a bank or twin 20 amp breakers wil not do well if they are all running at 20 amp loads.

We only use those twins when the panel is full and waiting to be upgraded soon, or when rarely used items need individual protection. I would change them out to single breakers, lose the tiwns.

Don't worry about the romex, some areas require conduit many do not, as long as its protected from the abuse and sunlight you are fine.

I never realized this. I always thought those twin breakers were just to save space. I'll try to keep this in mind. One idea for one of those dual 20amp breakers was to put half outlets on 1 20 amp side, and another half outlets on the other 20 amp breaker. Now that might be overkill.. but if I had like tv, some lights, and some tools running on one side and I started doing something on the other side (or a friend did) it wouldn't trip a 20amp. Maybe that is overkill. I don't know. I know it's rather hard to trip a 20amp breaker with common shop tools. What do you think? overkill? or smart planning?