Tom Cancelleri Posted February 18, 2015 Report Share Posted February 18, 2015 When I did my electrical for the shop I wanted to run 100amp originally. I was talked out of it due to never utilizing 100amps at one time. So I wound up with a 60 amp sub panel. I've since upgraded to more 220v machines, and now I wanna get a more powerful dust collection system either 3 or 5 HP. However the 60 amp isn't gonna cut it since a 5HP needs a 30 amp circuit, heater needs a 30 amp circuit and then the tool I'm connected to, plus lights isn't gonna work. I also need another spot in the panel for a 220V breaker. I'm panning on ripping out the 60 amp wire that is there now, open the wall (again!) and put a bigger panel in place. If I remember correctly 100amp requires #4 3 wire copper or #2 aluminum. I'd prefer copper though it's horribly difficult to find. It's roughly a 50 foot run from my main house panel to the garage (connected). No need for any seperate grounding rods. Since I haven't gotten a hold of my bro in law yet (he's an electrical designer for wiring entire communities, retailers, malls, etc) I was wondering if anyone knew a good supplier for the sought after copper wire since home depot and lowes are gonna be a bust. #4 copper is for 100amp correct? (will double check with my bro in law) but I'm impatient and wanna start trying to source the wire. Quote Link to comment Share on other sites More sharing options...
Vyrolan Posted February 18, 2015 Report Share Posted February 18, 2015 Doesn't 100-amp need #3? Link 50 feet doesn't require any changes for distance...the only change would be if >3 wires bundled. As an aside "horribly difficult to find" copper made me chuckle since we're reversed... Aluminum doesn't exist here and you can get copper almost anywhere. =p Edit: The * tables at the bottom actually do say #4 for 100-amp service...but I'm never clear on all that stuff that supposedly applies only to the main service feed (which main panel to subpanel is not). /shrug Quote Link to comment Share on other sites More sharing options...
Coop Posted February 18, 2015 Report Share Posted February 18, 2015 We're the same way. I didn't know they still sold aluminum wire. We buy conduit and connectors from a local elect. supply house to use in my industry for s/s cable runs. I needed 300' of the #3 for my shop upgrade and their price was barley under Home Depot's for that small of an amount. Quote Link to comment Share on other sites More sharing options...
pdxkris Posted February 18, 2015 Report Share Posted February 18, 2015 If you do end up going aluminum, I was required to use 1/0 for my 100A feed. From what I remember, there are a couple schools of thought on what's required and if you're doing permits, it's best to just call the local officials for clarity. Quote Link to comment Share on other sites More sharing options...
Trip Posted February 18, 2015 Report Share Posted February 18, 2015 Before you do anything, I'd revisit the 100a requirement... If you want the bigger panel for more breakers, that's one thing -- have at it... Just get the bigger panel, keep the existing service wire and breaker... BTW: I always recomend a 125a sub, even if you run a 60a service -- having the extra breaker lugs is nice... Now, if you feel you're going to use more than 60a, that's another thing all together... Sure, the breakers will add-up to over a 100a, but are you actually using that much power? Personally, I doubt it... I've got some pretty big tools, including three 5HP, a 6.5HP, several 7.5HP and one 20HP. Running most of my shop draws around 60a or so as long as I avoid the wide-belt sander... Get yourself a clamp-on meter and read the legs: http://www.amazon.com/Fluke-324-Temperature-Capacitance-Measurements/dp/B009AZ0TXE/ref=sr_1_2?ie=UTF8&qid=1424287376&sr=8-2&keywords=fluke+clamp BTW: if you get a clamp-on meter and have a few more bucks, get the 376 -- it reads in-rush (extreemly useful) and has a flex loop amp sensor (safety): http://www.amazon.com/gp/product/B0086963VC/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 If you want to save a few bucks: http://www.amazon.com/Fluke-323-True-RMS-Clamp-Meter/dp/B00AQKIEXY/ref=pd_sim_hi_3?ie=UTF8&refRID=132D7YYN12K7ZHAVRBFH -- but honestly, the 324 is a better deal... Quote Link to comment Share on other sites More sharing options...
Eric. Posted February 18, 2015 Report Share Posted February 18, 2015 I'm with Trip...probably not necessary. But I'm not the kind of guy to tell someone not to go bigger for no good reason since I do it all the time. I have a 50A sub-panel for the shop and I run a 220V heater, 2HP DC and a 3HP tool plus all my lights, stereo, etc all at once. Never tripped a breaker. My whole house is on a 100A panel and don't have issues...and my wife and kids like to use as much electricity as humanly possible...while I'm in the shop. Consider that. Quote Link to comment Share on other sites More sharing options...
Tom Cancelleri Posted February 18, 2015 Author Report Share Posted February 18, 2015 It comes awfully close If I get the Oneida Super Dust Gorilla DC it runs at 19.5 Amps, My 3hp Table saw runs at 14.5, my heater runs at 23 amps and my shop lights run at 5.3 amps. I could shut the heater off when using the DC, however the DC is on for almost every tool. That puts me at 62.3amps with the heat on. I suppose I could put my amprobe on and see what I'm drawing currently. My concern is upgradability. I do need space in the box for another 220v breaker for that DC when the time comes. I could change out the panel itself for additional slots. Quote Link to comment Share on other sites More sharing options...
Trip Posted February 18, 2015 Report Share Posted February 18, 2015 ==>Super Dust Gorilla DC it runs at 19.5 Amps, My 3hp Table saw runs at 14.5 Where exactly did you get these numbers? These look like full-load ratings, not nominal... Just because that what's printed in the manual or stamped on the motor plate doesn't mean that what they are... Again, get a meter and read the legs at the box... It's also one reason to actually get a decent meter -- if your 3HP saw is drawing 14.5, then somethings wrong... Quote Link to comment Share on other sites More sharing options...
Tom Cancelleri Posted February 18, 2015 Author Report Share Posted February 18, 2015 ==>Super Dust Gorilla DC it runs at 19.5 Amps, My 3hp Table saw runs at 14.5 Where exactly did you get these numbers? These look like full-load ratings, not nominal... Just because that what's printed in the manual or stamped on the motor plate doesn't mean that what they are... Again, get a meter and read the legs at the box... It's also one reason to actually get a decent meter -- if your 3HP saw is drawing 14.5, then somethings wrong... Going by manufacture specs. I've got a good amprobe to use. I'll see what it's actually pulling when I make a cut through a piece of 8/4. I thought that amps seemed a bit high, but they are there for a reason. Quote Link to comment Share on other sites More sharing options...
Trip Posted February 18, 2015 Report Share Posted February 18, 2015 ==>when I make a cut through a piece of 8/4 No doubt it'll rise to the load rating of 14.x -- no issues with that -- the nominal draw should be around 11a.... It's just that in a small shop, all kit is rairly at load at the same time... put the meter on the legs and see what the entire shop is drawing before pulling a new feeder... Don't get me wrong, if you want the 100a for the headroom, have at it... But before you invest the $$, see if it's a need to have -vs- nice to have... Quote Link to comment Share on other sites More sharing options...
dwacker Posted February 18, 2015 Report Share Posted February 18, 2015 Startup is what will get you even in a small shop. 5hp dust collectors will peak pretty high as will some other tools. You may just need to let the dust collector wind up before powering up something else that draws a heavy load. 2 Quote Link to comment Share on other sites More sharing options...
Trip Posted February 18, 2015 Report Share Posted February 18, 2015 ==>the dust collector wind up before powering up something else that draws a heavy load Yea, but again --- it's one tool at a time... DC spin-up is 2-3 seconds? By the time you hit the DC 'start' button and walk over to the tablesaw you're past inrush and wind-up... Now if you have something like a 15hp jointer, then things take a bit longer, but by then we're in the world of 3p anyway... The longest wind-up in my shop is the 3p jointer -- think it's about 4 seconds, but it's a monoblock head that weights more than most 4-posters -- that's a lot of steel to spin... Quote Link to comment Share on other sites More sharing options...
Tom Cancelleri Posted February 18, 2015 Author Report Share Posted February 18, 2015 Good points. I'm gonna check my amp draw this weekend with my heater running, lights on, current 1.5 hp dust collector running, and my tablesaw running. Honestly, this entire upgrade for the DC is for ducting reasons. I can run everything i have right now with no issues. It's adding a bigger DC that is what I'm trying to consider. Quote Link to comment Share on other sites More sharing options...
Vyrolan Posted February 18, 2015 Report Share Posted February 18, 2015 On the original topic, is #4 correct for 100A? What about for 80A? Seems like a lot of you guys have 50-60 in your subpanel...what's the wire feeding that? Quote Link to comment Share on other sites More sharing options...
BrandonD Posted February 18, 2015 Report Share Posted February 18, 2015 Copper is more prevalent here, although aluminum is sometimes used for the feeders from the main pole. My shop is run off of a 70A subpanel I installed myself with my electrical friend overseeing. I ran #6 THHN which is rated for 75A. For 80A, you'd need to run #4 THHN I believe, but I'm no electrician. Quote Link to comment Share on other sites More sharing options...
Tom King Posted February 18, 2015 Report Share Posted February 18, 2015 There's nothing in the world wrong with using aluminum wire for service entrance cable. Just use No-Ox or some such on the wire under the lugs. Every house I've ever built, or seen uses aluminum around here, including some upwards of one and two million dollar houses for service entrance, or to sub panels. Since you are in Virginia, you can buy wire and devices from an electrical equipment supplier to do your own work. The dedicated electric supply houses will sell stuff MUCH cheaper than you can find in the big box stores, and the counter men can also give good advice like size of wire. 100 amp service entrance wire will cost about half from Electrical Equipment Supply as you can get it from Lowes or Home Depot, and you can buy it by the foot. Make sure to get enough to have a few feet left over to throw away. Use plastic bushings, although if you don't have to replace the conduit, they should already be there. You need four conductors-three plus ground. The neutral is not bonded in today's code for a sub panel, so you need a neutral plus a separate ground wire. Quote Link to comment Share on other sites More sharing options...
BrandonD Posted February 18, 2015 Report Share Posted February 18, 2015 Do your homework and get price quotes from both box stores and electrical supply companies. I've run two sub panels within a couple years of each other; one time the electrical supply company came in way cheaper, the other time the box store was a cheaper. Quote Link to comment Share on other sites More sharing options...
Trip Posted February 18, 2015 Report Share Posted February 18, 2015 ==>There's nothing in the world wrong with using aluminum wire for service entrance cable. Absolutely -- as long as the municipality, utility and inspector allow it... ... and in parts of the US, they don't... Code compliance and inspector whims are just two reasons hiring a pro for service pulls and setting sub-panels can pay off in the long run... Quote Link to comment Share on other sites More sharing options...
Tom Cancelleri Posted February 18, 2015 Author Report Share Posted February 18, 2015 I've got pros to help me. Though I do the work, they "supervise" Quote Link to comment Share on other sites More sharing options...
Greenaqua Posted February 18, 2015 Report Share Posted February 18, 2015 I just had aluminum 200amp service rerouted for my house because the original was in the way for an upcoming swimming pool. It was 4/0 4/0 and 2/0 for the neutral. Copper would have been 2/0 and much more money. All new houses going up in my area have aluminum service feeds being put in. There may be some cities that don't allow aluminum at all so calling the city would be ideal. For your case with a sub panel I personally would run copper and pay the extra cost. I have seen it online at home depot etc. I think you would have to order it for some of the heavier gages and wait a week or so for delivery. Quote Link to comment Share on other sites More sharing options...
wtnhighlander Posted February 18, 2015 Report Share Posted February 18, 2015 Aluminum has a greater risk of developing fatige cracks and breaking away from the lugs. Quote Link to comment Share on other sites More sharing options...
Tom King Posted February 19, 2015 Report Share Posted February 19, 2015 I understand there have been all sorts of problems with aluminum branch wiring, but I've never even seen any of that. I've also heard of problems with very large connections coming loose in sub stations. I did a google search to see where aluminum service entrance cable was not allowed, and couldn't find anything-not saying there is not some municipality somewhere that doesn't allow it. Around here, in big box stores and electrical supply houses, this is what's used more than anything else for SEC, either underground or feeding sub panels. It's commonly called moble home service entrance wire, and comes in a bunch of sizes. http://www.southwire.com/products/MobileHmFeeder.htm It's okay for direct burial. I probably have several hundred yards of it underground running around our farm to various buildings, both sub panels and main panels from various disconnects and meters. No problems in 35 years. I changed our old 200 amp service entrance cable in our house when I built an addition over where the meter used to be, and had to use an outside disconnect, so as not to have to move the main panel. There was absolutely nothing wrong with the 28 year old connections in that 200 amp panel. You do have to use No-Ox and properly tighten the lug properly. Quote Link to comment Share on other sites More sharing options...
Janello Posted February 19, 2015 Report Share Posted February 19, 2015 100 Amp service to a main lug sub panel = #3 thhn in conduit. You can run #4 on 90 Amps. Do yourself a huge favor and go copper, it's a better conductor and doesn't get as hot. will not loosen lugs over time. It's not the place to cheap out. People will tell you all day long there is nothing wrong with it. Ask 10 licensed electricians which way to go, and 9 will tell you copper. 1 Quote Link to comment Share on other sites More sharing options...
Vyrolan Posted February 19, 2015 Report Share Posted February 19, 2015 Around here, in big box stores and electrical supply houses, this is what's used more than anything else for SEC, either underground or feeding sub panels. It's commonly called moble home service entrance wire, and comes in a bunch of sizes.http://www.southwire.com/products/MobileHmFeeder.htm Not here in good ole Chicagoland. Even here in my smallish suburb it's absolutely no aluminum. Only copper allowed and everything in conduit. Makes me jealous of people able to bury PVC and full that feeder cable. Lucky bastards. Quote Link to comment Share on other sites More sharing options...
Janello Posted February 19, 2015 Report Share Posted February 19, 2015 By the way...I totally agree with trip. You probably don't even need the upgrade. Everything cycles. You'd need to fire up everything at the EXACT same time to exceed the 60amps. It's like hitting the lotto. Quote Link to comment Share on other sites More sharing options...
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