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I'm running 240v out to the garage for an air compressor.
Was told the compressor draws maybe 30amp? Get a 50 amp breaker?
(Champion 5hp/80gal)
So I called the electrician I usually use and was blown away by the estimate.
My garage is 10ft from my house and maybe 25/30ft total from my breaker box...$3053.00!
IS this out of line? The wire at $30ft kinda blows me away.
Below is the itemized estimate.
Any info/similar job prices would help. Thanks.
It looks like that estimate is only giving you quantities, ie Romex 6-3 wire - per foot: 30 units = 30'. I don't see any price per unit or total prices of materials there so pretty much impossible to see if or where you're being overcharged. A 50' roll at Home Depot runs $6.28 a foot, so that line item's actual value is $188.40 at HD's price. No idea what kind of markup the electrician puts on it, but I would suspect something similar to a mechanic marking up a part from his jobber price to the schmuck walking in from the street price.
What's his hourly rate?
You could always ask for a revised price if you were to do menial tasks like digging the trench and backfilling it, etc.
Labor charge is more that likely 1/3 of the quote @100.00 + per/hr
Copper wire is crazy priced now a days.
If your garage is that close to the house I would be tempted to run the compressor from the existing house panel via a 30a rated 4wire dryer receptacle, run the air line only to the shop that way you will not hear the compressor run and save a bunch of cash. If someone is in the house while you are working in the shop ask them to bring you a beer after the compressor runs 3 or 4 cycles
Yes prices are crazy right now. Do a bit of research at your local Menards or Home Center for some Aluminum mobile home entrance 4wire cable to make the run between the buildings. Here and in most National Electrical Code regulated areas the system neutral and grounding conductors need to be separated and a separate grounding electrode system (Ground Rods and #4cu) need to be installed at the detached structure and or sub panel/disconnect.
Get a second quote and look at some you tube vids to understand the "Sub Panel" / Outside Branch Circuit you are needing at the shop.
I also just noticed the 1-1/4pvc to run between the buildings and under the sidewalk are not on the estimate unless I am just not seeing it. And yes like Cutty said any of that material and grunt work he will let you do will save on material mark up and labor charge time.
As others have said, do as much as you can/want yourself. I have the same compressor, and ran 40' of #6, but from an existing 100A subpanel in my detached garage. Your project is much more involved. Maybe consider a subpanel for future expansion? My subpanel also has 230V for a swimming-pool pump, and lights/120V receptacles.
The wire gauge or capacity controls what breaker size you need. Your load and distance determines your wire gauge. If 40 amps would suffice, that will lower you wire cost. I believe 50 amps needs 6 gauge wire.
I've done all my own wiring for the houses, shop, and barns. In VA the homeowner is legally allowed to perform wiring on his/her own property. This is trivially easy. If you only plan to use 30A, there's no need to run 50A, but if you want extra capacity for a welder or larger compressor later, then the 50A is not a bad idea. Conduit or not is your call. UF wire doesn't need to be in conduit but needs to be 2ft down. Conduit can be at a more shallow depth. I've personally used direct burial cable but my runs have been several hundred feet.Yes, you still need to protect the cable where it comes out of the ground with conduit, but that's not that much distance. The actual wiring is no more difficult than wiring your car.
I’m not an electrician but done plenty for myself and worked in an air compressor shop.
1) be sure of the load. The electric motor motor itself should have a stamped metal tag (some are stickers)listing the specs . Be sure it is lists correct voltage ,240 v, Phase or PH, 1, and full load amps will be FLA . This is the amps it will pull when running, but it will pull up to 5 times FLA, momentarily on start up, the stranded THHN wire is better suited for that. ( 30 amp seems a little high).
2) most true 5 Hp electric motors will require a magnetic starter to handle the initial load and provide thermal protection. There are other methods used that may work but be sure that if the FLA is much more than 15, something other than wiring direct to the pressure switch should be used. The size of the contacts in the pressure switch will not handle the load on start up without failing.
Last edited by 1of1442; Dec 1, 2022 at 09:25 PM.
Reason: Changes
2) most true 5 Hp electric motors will require a magnetic starter to handle the initial load and provide thermal protection. There are other methods used that may work but be sure that if the FLA is much more than 15, something other than wiring direct to the pressure switch should be used. The size of the contacts in the pressure switch will not handle the load on start up without failing.
"hobbyist" quality 5HP air compressors typically use the same air pressure switch as smaller compressors. And many ""5HP"" units aren't actually 5HP motors.
But yes, 5HP is where it's a good idea to get a real magnetic starter. The funny thing I ran into is most starters barely go down low enough to actually protect at that current. The ""5hp"" rated starter I have has the dials turned all the way down and they're still several amps above the motors FLA. So is it worth it at 5hp? ¯\_(ツ)_/¯
Starters do seem to be standard once you hit 7.5HP.
The motor data plate will tell you exactly the current draw and from this you can determine if it's a true 5HP motor or not. Champion is a higher quality compressor and their motors are usually correctly rated. A true 5HP motor will pull just under 30 full load amps at 230V single phase. If the data plate has a smaller number, it isn't 5HP. If FLA says "SPL" ("special"), it's not a real 5HP motor.
Also if it is only 15 feet away from your house, why is he going under the sidewalk? Unless your city codes require buried wiring, over head would be cheaper. A weather head at both ends should keep the wire high enough for safety.
Yes, price of copper has become crazy high! As Joe said, also in Georgia the homeowner can run his own wiring and have it blessed before final turn on by the local inspector. Get with your electrician and talk with him about doing some of the install work yourself, especially the outdoors work, digging, burying, mounting boxes and pvc conduit, pulling wiring thru the pvc (borrow a buddy's fish tape). Get the "Stanley" as in Stanley tools, "Complete Wiring" book from Lowe's or Home Depot. Also as mentioned above, you may want to run a "heavier" service out to the garage for future expansion.
IMO, you will be happier in the long run if you install a subpanel. Then you plenty of room for expansion and not have to say "Why didn't I" When we wired my workskhop, we put in a 100 Amp subpanel and I never tripped that breaker, ever.
I've always done my own electrical - three-way switches are a breeze and very handy, ensure you're sober if wiring a four-way switch (they're fun). I wired/installed a sub-panel in my man-cave w/ dedicated (separate) ground & neutral. Created circuits based upon (likely) demand. Duplexes are all polarized. Lighting circuit dedicated separately from power circuit(s).
IMO, you will be happier in the long run if you install a subpanel. Then you plenty of room for expansion and not have to say "Why didn't I" When we wired my workskhop, we put in a 100 Amp subpanel and I never tripped that breaker, ever.
I had the same thought, but I assumed the garage already had 110 circuits for lights and outlets. Adding a subpanel runs the risk of MIGHTASWELL-ing itself into a completely new shop.
I had the same thought, but I assumed the garage already had 110 circuits for lights and outlets. Adding a subpanel runs the risk of MIGHTASWELL-ing itself into a completely new shop.
Thanks for ALL the comments guys.
it’s helpful for some who knows NOTHING about electric…as far as I’m concerned it’s black magic.
I would NEVER attempt to do it myself. Carpentry…sure…anything you need I can do.
But not electric.
I got another quote today…$2300 and the guys are reputable.
Books like these will tell you all you want to know to do it yourself. Don’t be afraid of the building inspectors. They are usually really helpful to the homeowners.
If you’re willing to do some reading and study some YouTube videos, basic wiring isnt difficult. Running the wiring is by far the hardest and most time consuming part of the project.
if the garage already has power, I’d consider tearing out the original supply line, and running a new cable big enough to support your current needs, and maybe some future wants. Once the new cable is run, install a sun panel.
As for the wire, check out your nearest metal recycling center. There is a place near me that deals in non-ferrous metals. All the big electrical contracts sell their leftover wire after a job is completed. if the job takes 400 feet of cable, they quote the job with a 500 ft spool. Instead of storing spools of wire with 100 feet left on it, they just sell the leftover.
I bought a partial spool if 6/3 wire for my welder outlets for basically scrap price.
Books like these will tell you all you want to know to do it yourself. Don’t be afraid of the building inspectors. They are usually really helpful to the homeowners.
Agree w/ Gary. This book has excellent pictures & well-written text. Meredith Books (publisher).
I've always done my own electrical - three-way switches are a breeze and very handy, ensure you're sober if wiring a four-way switch (they're fun). I wired/installed a sub-panel in my man-cave w/ dedicated (separate) ground & neutral. Created circuits based upon (likely) demand. Duplexes are all polarized. Lighting circuit dedicated separately from power circuit(s).
straying off topic, but once I understood to concept of traveler wires, 3 way and 4 way switches were a breeze...................
https://www.youtube.com/watch?v=iX3kxAA2L4Q
As others have said, do as much as you can/want yourself. I have the same compressor, and ran 40' of #6, but from an existing 100A subpanel in my detached garage. Your project is much more involved. Maybe consider a subpanel for future expansion? My subpanel also has 230V for a swimming-pool pump, and lights/120V receptacles.
220, 221- whatever it takes.. that line gets quoted quite a bit around here!
I vote for leaving the compressor in the other garage.
1- it's closer to the panel
2- you don't have to size the new panel for it
3- you won't hear it
My neighbor has his setup like that, and it's nice. He even put a contactor in to run a switch in the main shop, in addition to the ball valve shut off.
Another tidbit: get some piping to extend the tank drain for easier draining. I have a small ball valve I can kick open with my foot. Hose goes outside.