Can someone check my numbers

[supratreo]

I thought it would be easier to just make another thread that only has information.
so i currently have a 220' roll of MHF 2-2-4-6 which i was planning on using for my shop.
discussing this in the other thread it looks like it might be an issue with the distance I'm trying to cover (198' panel to panel).
i was told i would have to de-rate to 60-75A.
i tested voltage at my main today and i get 245v, i figured that would help when calculating voltage drop.
I'm now considering going 2/0-2/0-1-4 MHF. according to Southwire this would be good for 100A but that's using THWN-2/XHHW-2. the MHF I'm looking at is RHW-2 but I'm not knowledgeable enough to know how that factors in.
this is going into 1-1/2" sch40.
any advice or other options?

 

[Bert_]

Most people are basing voltage drop on the 3% suggestion in the code book. It is not a requirement.

If your line voltage is always above 240v, then 3% is very conservative. The other thing to consider is how much load will normally be on the panel? A little voltage drop once in a while isn't the end of the world.

Personally I would probably run the #2

 

[mike93lx]

The 245v reading was at one moment. To count on that, you'd want to have a bunch of data points.

Unless you have real concern that 60ish amps. Isn't enough, run the #2. What equipment will be out there?

 

[supratreo]

its not that i don't think it will be enough, but its one of those things where i was thinking "the more the marrier" and "too much is better than not enough"
biggest amp draws would be compressor, 2 post lift, welder.
other than that I'll have lighting, TV, fans, and bench tools.

 

[mm08822]

What are your expected simultaneous loads expected to be?
Unless you really expect simultaneous usage to be at the high end, 60-75-90A, then a larger size cable is needed.
2/0 MHF is about $5/ft, so nice to have will cost you $1k. And then you have something left to trip over....#2 MHF.

I would put my money into pvc conduit to protect the mhf long term. You could even upsize that for a larger feeder if ever needed in 2050.

 

[mike93lx]

its not that i don't think it will be enough, but its one of those things where i was thinking "the more the marrier" and "too much is better than not enough"
biggest amp draws would be compressor, 2 post lift, welder.
other than that I'll have lighting, TV, fans, and bench tools.

"what if" is a really expensive line item in a project.

If you have a big HVAC, a big compressor and a plasma cutter, I think 60a could pose a challenge, beyond that, 60a is pretty safe for a single person workshop

 

[Metal-Marc]

"what if" is a really expensive line item in a project.

"While you're in there" is another one.

 

[Bert_]

Realistically if you were going to be consistently drawing 100 amps, you would be installing larger than a 100A panel.

You by yourself can't weld and run the lift at the same time. Only consider the larger one.

Around here it's rare to see line voltage under 240V. I consider voltage drop, but it's pretty rare for me to up size conductors because of it.

 

[mike93lx]

You by yourself can't weld and run the lift at the same time. Only consider the larger one.

To be fair, the compressor can kick on while the welder is running and the a/c is running.

What about an EV charger???

 

[supratreo]

Thank you all, i think I've decided to just sick with the #2.
not doing something "while I'm in there" has bit me in the *** a few times which is why i was asking but like you mentioned, i won't be running all of the loads simultaneously. there's a good chance i won't ever have A/C as it stays fairly cool and i have a small port-a-cool.
IF i do ever add a system it will be a mini split. there won't be an EV charger in this shop.
the conductors will be in PVC from end to end.
also, since this cable is technically rated for 100A, do i still run a 100A breaker? since i have to de-rate it due to the run i would think the breaker size would go down as well.

 

[mike93lx]

Thank you all, i think I've decided to just sick with the #2.
not doing something "while I'm in there" has bit me in the *** a few times which is why i was asking but like you mentioned, i won't be running all of the loads simultaneously. there's a good chance i won't ever have A/C as it stays fairly cool and i have a small port-a-cool.
IF i do ever add a system it will be a mini split. there won't be an EV charger in this shop.
the conductors will be in PVC from end to end.
also, since this cable is technically rated for 100A, do i still run a 100A breaker? since i have to de-rate it due to the run i would think the breaker size would go down as well.

No it's only rated for 100a if feeding the entire load of a dwelling. 90a max for your use

 

[Bert_]

The 90 vs 100 thing is a big debate. The code says 90a unless it's the entire load of a dwelling.

If you can find a 90A I'd probably go with that. But if you can't find a 90 and there's a 100 sitting on the shelf I wouldn't lose any sleep over it.

 

[supratreo]

thank you guys. looks like i might have some electricity this weekend.

 

[supratreo]

Last question i swear.
By everyone's recommendation here I'm going to go with a Square D QO panel. I didn't realize you had to use QO breakers as well which is fine but why are they 3x the price of HL breakers?

 

[Bert_]

QO is over hyped in my opinion. They are good panels but not that special.

 

[supratreo]

ok good because I'm thinking about going with the HL. the QOs my local HD has are 24 spaces or less but about 2x the price of a HL which has way more options.

 

[mm08822]

Nothing wrong with Homeline series. It was made(priced) to compete against Siemens, etc. w/o cutting the QO icon product price.

What ever brand you buy, make sure the panel has way more spaces than you could possibly need, e.g. 24-30 min. It's only pennies more.

 

[supratreo]

https://www.lowes.com/pd/Square-D-100-Amp-24-Spaces-48-Circuit-Main-Breaker-Plug-On-Neutral-Load-Center-Value-Pack/50311147

this is what i'm leaning towards. I wasn't big on the "value pack" but for an extra $40 i think its worth it.

 

[theoldwizard1]

i tested voltage at my main today and i get 245v, i figured that would help when calculating voltage drop.

Most power companies spec their voltage as +/- 10% (?). Don't bet on get 245V all of the time

 

[theoldwizard1]

What are your expected simultaneous loads expected to be?
Unless you really expect simultaneous usage to be at the high end, 60-75-90A, then a larger size cable is needed.

CONCUR !

Unless you are going to have a welding party where all you buddies bring their welders, 60A circuit breaker on the feeder end is adequate.

Worst case would be an electric hot water heater, a mini-split/AC, air compressor and a plasma cutter. If that trip the breaker, turn off the water heater and the AC while using the plasma.

 

[sparky 1971]

https://www.lowes.com/pd/Square-D-100-Amp-24-Spaces-48-Circuit-Main-Breaker-Plug-On-Neutral-Load-Center-Value-Pack/50311147

this is what i'm leaning towards. I wasn't big on the "value pack" but for an extra $40 i think its worth it.

There's nothing wrong with that panel, it's the same one I put in my garage a few years ago. Make sure you pick up a couple of ground bars, SQ D doesn't include them with almost all panels and this one won't have one; the sticker on the end of the panel will tell you which ground bar you will need and get two of them, one for each side. And get a neutral lug kit for one of the ground bars; the ground for the MHF will fit in the ground bar, but you have to look at it just right while using the proper words and trying to keep the strands from coming apart and I don't think it's worth the effort. It's so much easier to use the adapter that I keep a couple of them on my truck.

https://www.lowes.com/pd/Square-D-1-in-Neutral-Kit/3363650

 

[Metal-Marc]

Unless you are going to have a welding party where all you buddies bring their welders, 60A circuit breaker on the feeder end is adequate.

Unless you think about resale value.

What's the price for 200' of cable for 60A and what's the price for 200' of cable for 90A.

 

[mm08822]

Unless you think about resale value.

What's the price for 200' of cable for 60A and what's the price for 200' of cable for 90A.

Already has the mhf to support 60a. 2/0 = $1k + tax, maybe shipping.

 

[wyliesdiesels]

biggest amp draws would be compressor, 2 post lift, welder.
other than that I'll have lighting, TV, fans, and bench tools.

without knowing the HP rating on the comp, this info is useless

same goes for the welder but since its intermittent use usually not an issue

if the comp is 5HP or less, and the welder is not a huge draw, you could get by with 60-75a easily with very minimal voltage drop. I would go with the #2 and save the change for beer money

 

[wyliesdiesels]

also, since this cable is technically rated for 100A, do i still run a 100A breaker? since i have to de-rate it due to the run i would think the breaker size would go down as well.

#2 AL is rated for 90a not 100a and you dont have to derate it or reduce the breaker due to run length. that is only a suggestion.... no NEC requirement to do so...

 

[wyliesdiesels]

Unless you think about resale value.

What's the price for 200' of cable for 60A and what's the price for 200' of cable for 90A.

how much property resale value is there really here? not much unless the buyer is specifically looking for this feature in a property

 

[Bert_]

Unless you think about resale value.

Be honest... Zero difference

 

[Metal-Marc]

Be honest... Zero difference

Yeah, like if any of you will look at a house FS and find the shop has a 30A or 60A feed will not think to themselve, "gee, I wish it was at least 90A"

Yeah, be honest.

What if I bring in some more equipment in the shop next year?

While I'm in there digging a trench, I might as well spend a few bucks and get a proper cable to feed the shop, and some fiber optic cables too.

Yeah, be honest.

Whether it is tools, sq/ft, lights, amps, projects, no one here likes to have the bare minimum.

 

[Bert_]

Yeah, like if any of you will look at a house FS and find the shop has a 30A or 60A feed will not think to themselve, "gee, I wish it was at least 90A"

Yeah, be honest.

What if I bring in some more equipment in the shop next year?

While I'm in there digging a trench, I might as well spend a few bucks and get a proper cable to feed the shop, and some fiber optic cables too.

Yeah, be honest.

Whether it is tools, sq/ft, lights, amps, projects, no one here likes to have the bare minimum.

You have any idea what percentage of buyers care about that? Many will store some stuff in the building and never use more than the lights and a couple outlets.

 

[supratreo]

Hey guy. so ran the wire and installed the panel yesterday. just need to make the main connection.
i think I'll just have HD order the 90A breaker as there's a $30 difference between the 90 and 100A.
also, I'm not worried about resale, we built this house on 2 acres 20 years ago and this shop is my workspace, i don't see myself going anywhere anytime soon.

 

[mm08822]

Way too much worry about the next guy. Enjoy it the way you want it.

The next guy will get over it.

 

[Chuckster in NJ]

Hey guy. so ran the wire and installed the panel yesterday. just need to make the main connection.
i think I'll just have HD order the 90A breaker as there's a $30 difference between the 90 and 100A.
also, I'm not worried about resale, we built this house on 2 acres 20 years ago and this shop is my workspace, i don't see myself going anywhere anytime soon.

 

[Shiftless]

You have any idea what percentage of buyers care about that? Many will store some stuff in the building and never use more than the lights and a couple outlets.

Yeah
So many folk treat a garage like a conveniently located self storage unit and park their cars and trucks outside in the weather while the worn out furniture and used mattresses and cardboard boxes of **** sit nice and dry in the garage. I was talking to a guy today who has a 4 car garage and says he can’t park in any of the spaces because of stored stuff.

So a future buyer will get by fine with 60 amps for the LED lights and maybe one or two little battery chargers for his leaf blower etc.

60 amps is probably 10 times as much as most non GJ members ever use in their garage.
One of my well to do friends has a 3 car garage illuminated by 3 LED bulbs in porcelain bulb holders 10 feet above the floor. One receptacle feeds a spare refrigerator, and another feeds a trickle charger for his seldom driven sports car. That’s it. He doesn’t have a work bench. Hires out most all of his yard work.

 

[cpakalolo]

Nothing wrong with Homeline series. It was made(priced) to compete against Siemens, etc. w/o cutting the QO icon product price.

What ever brand you buy, make sure the panel has way more spaces than you could possibly need, e.g. 24-30 min. It's only pennies more.

I've installed quite a few Square D panels. Hom is out there. They are cheaper and you can use several brands in them. QO is more expensive, but built quite a bit better. Now I cringe when I see electric heat on them. This is where they go bad. I have had to do sub-panel because customers think the panel is good enough when it isn't. When it is really cold you don't want to bake your panel because it'll take some time to get someone out there. QO is only really expensive if you have to buy a bunch of piggy back breakers later on.