a little power apparently goes a long way

[toolguy1000]

when i brought power into the 12'x20' garage ~10 years ago, and not being into woodworking to the extent i am now, i thought a 30A service would be more than enough for the occasional project. fast forward to today, and the garage is now a shop with 2 10" CI contractor TSs for starters. well, i acquired a delta 50-850 dual voltage 1.5hp dust collector last weekend and was concened that the 30A service would be insuffiecient to the task of activating a 1.5hp TS, a 20gal craftsman shop vac and the aforementioned DC simultaneously. this video demonstrates that those three appliances can be simultaneously activated, along with the delta ap400 DC(wired for 110v) that the 50-850 will replace (the ap400 was accidently left in automatic activation when testing the 50-850 setup).

http://www.youtube.com/watch?v=0R0ed...ature=youtu.be

i just found it interesting that, with all the posts i see on a variety of forums that "more power" is always the suggestion whenever the topic of shop service is raised, apparently 30A performs well enough.

[woodturner]

was concened that the 30A service would be insuffiecient to the task of activating a 1.5hp TS, a 20gal craftsman shop vac and the aforementioned DC simultaneously.

Yes, that is not likely to work. If you start them one at a time, as in your video, you will likely be able to get them all running, but when you place them under load by trying to cut wood, for example the lights will dim and the breaker will eventually pop.

[greenacres2]

And...depending on the guage of the feed...you might well be heating wiring to a severe extent somewhere. Unfortunately, it might become easy to find out where!!

earl

[leehljp]

When he said, at the end, when you use 220, your amperage decreases. So, was all of his tools on a 30 amp 220 line? Was his shop vac on 220 too? Was everything else on 220?

Something didn't make total sense unless all 220 was the case.

[toolguy1000]

Yes, that is not likely to work. If you start them one at a time, as in your video, you will likely be able to get them all running, but when you place them under load by trying to cut wood, for example the lights will dim and the breaker will eventually pop.

if you view the video again, i believe you will notice that the two DCs, the shop vac and the RAS are, essentially, all activated at the same time. my next test, once the 50-850 is installed in place of the ap400, will be to bevel rip some dimensional material to see what happens when the saw dust creating tool is activated. any suggestions as to what type of dimensional material would make for an interesting test?

the only previous experience i had with tripping a breaker was in a set up preceeding my adoption of ivac switches to automatically activate slave tools. i was running the same shop vac, the ap400 and a 2 hp router in a table through a craftsman autoswitch ( http://www.sears.com/shc/s/p_10153_1...sid=21x1399601 ) , all on ONE 20A 110V circuit. and it only tripped the 20A breaker when i attempted too deep of a cut with the router. it never happened under load when using a TS or BS or RAS or jointer with the same two slave tools through the same autoswitch on the same 20A 110v circuit.

[toolguy1000]

And...depending on the guage of the feed...you might well be heating wiring to a severe extent somewhere. Unfortunately, it might become easy to find out where!!

earl

the subpanel was installed by a licensed electrician with a permit. 10/3 wire off a 30A double pole breaker in the main panel to the subpanel in the garage/shop. since 10gauge wire is the appropriate gauge for use with a 30A breaker, the liklihood of the subpanel feeder wire overheating is remote. now, had someone in a perhaps more rural area where permits and licenses aren't the norm used 12gauge wire as a feeder on a 30A breaker, that is asking for trouble.

[toolguy1000]

When he said, at the end, when you use 220, your amperage decreases. So, was all of his tools on a 30 amp 220 line? Was his shop vac on 220 too? Was everything else on 220?

Something didn't make total sense unless all 220 was the case.

i'm not too sure what the question is here. perhaps you could flesh it out so it's a bit clearer.

[Dal300]

the subpanel was installed by a licensed electrician with a permit. 10/3 wire off a 30A double pole breaker in the main panel to the subpanel in the garage/shop. since 10gauge wire is the appropriate gauge for use with a 30A breaker, the liklihood of the subpanel feeder wire overheating is remote. now, had someone in a perhaps more rural area where permits and licenses aren't the norm used 12gauge wire as a feeder on a 30A breaker, that is asking for trouble.

According to NEC, 30 amps on a 10awg circuit @ 120V is only appropriate up to 38 feet.
30 amps on a 10awg circuit @ 240V is appropriate up to 75 feet.

Now, when you use your 10/3 240V circuit terminated by a sub panel and split into single 120 volt circuits, you are back to the 38 foot limit again.

Then again, the only tools that will operate at maximum amperage draw are the dust collector and anything else that operates at maximum output at all times. Your saws and routers don't do that. They only reach maximum current draw when they reach LRA, (Locked Rotor Amps), that is, when they trip the breaker.

If it were me, I would measure voltage drop at the sub panel main breaker both when all machines are off and when all machines are under the full load you normally put to at the same time. I would also measure, (If possible), voltage drop when all machines start up at the same time.
Anything over 2% is not acceptable and indicates the need to fish 3 - 3awg wires through the existing conduit to replace the existing 10awg wires.
I hope this takes all the wondering and maybe's out of the equation for you.

Good Luck, we don't want to hear that you burnt down the garage or even burned out a machine due to high resistance because of lack of voltage.

[pelligrini]

I don't see much of a problem, sounds like it works too. I'd probably still check the voltage drops. It's probably getting close to capacity with all 3 impellers spinning up along with a blade all at once.

I couldn't find the rated full-load of the 50-850 during a quick search. A Grizzly G0732 Contractor saw with a 1 1/2 HP 3600 RPM motor is stated as 5.7A@220 Full-Load on their spec sheet. I'd assume the 50-850 motors would draw similar. A new craftsman 20 Gal (6.5 peak hp, model 17762) draws 12 amps according to the sears sales listing. I couldn't find the draw for a AP400, but a Jet 650 pulls 7A@115. If I add 'em all up I get 17.7A on one leg and 12.7 on the other, assuming the 110 machines are on two separate circuits on separate legs. Could be done differently, but unless one leg is overloaded they are all pulling 20.9 amps (or so) on the 30A 220v service.

*edit I might have totally blown my calcs above, I think it's really 23.4 on one leg and 18.4 on the other assuming said wiring.

[toolguy1000]

According to NEC, 30 amps on a 10awg circuit @ 120V is only appropriate up to 38 feet.
30 amps on a 10awg circuit @ 240V is appropriate up to 75 feet.

good. it's less than 40' from the main panel to the sub panel.

Now, when you use your 10/3 240V circuit terminated by a sub panel and split into single 120 volt circuits, you are back to the 38 foot limit again.

Then again, the only tools that will operate at maximum amperage draw are the dust collector and anything else that operates at maximum output at all times.

the new (to me) dust collector (delta 50-850) doesn't operate continuously at maximum amperage draw. it peaks @ 60A for 2 seconds @ start up and then settles back to ~ 12A during continuous operation.

Your saws and routers don't do that. They only reach maximum current draw when they reach LRA, (Locked Rotor Amps), that is, when they trip the breaker.

If it were me, I would measure voltage drop at the sub panel main breaker both when all machines are off and when all machines are under the full load you normally put to at the same time.

in our area, code, at the time of the installation, did not require a sub panel main breaker.

I would also measure, (If possible), voltage drop when all machines start up at the same time.
Anything over 2% is not acceptable and indicates the need to fish 3 - 3awg wires through the existing conduit to replace the existing 10awg wires.

no conduit. 10/3UF buried 2' deep. again, installed 10 years ago by a licensed electrician with permits pulled and installation inspected. and wouldn't 3 awg really handle something in excess of 60A ( http://electrical.about.com/od/wirin...twiresizes.htm ) ?, possibly 80-100A? if i'm right, wouldn't that constitute significant overkill for a 30A panel?

I hope this takes all the wondering and maybe's out of the equation for you.

i don't have any "wonderings and maybe's". i was merely passing along something i was a bit surprised to discover. after all, whenever i read posts about shop electrical service, i always see a disproportionate number of posts to the effect that if a shop doesn't have it's own 2 billion gigawatt power generating plant, then it's underpowered.

Good Luck, we don't want to hear that you burnt down the garage or even burned out a machine due to high resistance because of lack of voltage.

thanks. i've been working with the existing service for the past 10 years, and had almost my full compliment of machines for the past 5 years. i imagine a problem would have made itself apparent by now.

lastly, i was just trying to let others know my experience with effectively using what's at hand and how far it can go safely. for those who feel a 2 billion gigawatt power generating plant is the minimum acceptable standard for workshop power, have at it.

[leehljp]

Oh, that was you in the youtube video.

[All Thumbs]

lastly, i was just trying to let others know my experience with effectively using what's at hand and how far it can go safely. for those who feel a 2 billion gigawatt power generating plant is the minimum acceptable standard for workshop power, have at it.

I'm sure some famous person once said, "I'm fascinated by people that argue the theoretical when confronted by the empirical."

If not, you can attribute the quote to me.

[greenacres2]

lastly, i was just trying to let others know my experience with effectively using what's at hand and how far it can go safely. for those who feel a 2 billion gigawatt power generating plant is the minimum acceptable standard for workshop power, have at it.

It was cool to see that--i'd have never figured a 30 amp panel could pull it off. I'd not seen multiple tool switches in operation, and now that i'm working with a DC (not in the habit yet, but trying) that video showed me a way to help the habit along. Thanks!!

Comment i made early on was based on the number of house/garage fires i've worked due to overloaded circuits. More often than not a $2.49 power strip is involved, sometimes plugged into a brown extension cord. Not your case for sure!!

earl

[Dal300]

Sorry about the "3awg" comment, I meant 8awg. Sometimes my fingers aren't as fast as my supersonic brain farts.

lastly, i was just trying to let others know my experience with effectively using what's at hand and how far it can go safely. for those who feel a 2 billion gigawatt power generating plant is the minimum acceptable standard for workshop power, have at it.

[woodturner]

if you view the video again, i believe you will notice that the two DCs, the shop vac and the RAS are, essentially, all activated at the same time. my next test, once the 50-850 is installed in place of the ap400, will be to bevel rip some dimensional material to see what happens when the saw dust creating tool is activated. any suggestions as to what type of dimensional material would make for an interesting test?

12/4 oak jammed into the saw blade could be a good "stress" test ;-)

The motors will draw about 3 times the rated max current on startup - so start them one at a time, not simultaneously.

10A is a good rule of thumb for running current draw on a 1 HP motor, but the nameplate rating is likely to be more accurate.

Your dust collector and vacuum should draw little current when unloaded, so unless you are completely filling the hose with dust and bogging down the fan, you should be fine with those.

The saw is the motor that will vary the load - it can jump nearly to startup current as it hits a tough patch of wood. However, breakers trip due to sustained moderate overcurrent or massive overcurrent. So, if you stall the saw motor for 5 minutes, the breaker will likely eventually trip after a minute or two. If you hit a knot, however, and draw 40A for a few seconds, the breaker won't trip.

So are you running 110 VAC or 220 VAC? I understood 110 VAC @ 30A, but if it's 220 VAC @ 30 A, you should be fine.