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Tamper84
05-29-2012, 09:58 PM
Well I am getting ready to re-wire my shop. I do plan on a lathe going in there along with a mill. I already have my welders/air compressor. Wich runs off of 220. And from you guys and some research online if I would need a phase converter I will need 220 for that. Also idk if I can run multiple machines off of one converter. More research is needed on that. But I am thinking of running a 200 amp service just for the garage. That would be more then plenty correct?

The service for the shop is split at the meter. One line goin to the shop and the other to the house. And the only thing I can think of that would be running 220 at the same time would the compressor and maybe something else.

Thanks,
Chris

Dr Stan
05-29-2012, 10:01 PM
I have a free standing shop and installed 200 amp service. Two lathes, a mill, a MIG, two air compressors, drill press, an electric stove, misc grinders etc. So far I've had plenty of power.

Tamper84
05-29-2012, 10:51 PM
Thank you Dr. Stan!!!

lakeside53
05-30-2012, 12:45 AM
I have the same. No problems. Plently of power.

Fasttrack
05-30-2012, 01:55 AM
My biggest current draw would be my welder. At full output (400 amps and roughly 53 OCV) it draws about 120 amps on 220V. It's very rare that I have the beast turned up to 400 amps. I don't think I ever will now that it is in a garage. Nothing that needs 400 amps will fit in the garage ... :p

Anyway, 200 amps should be plenty. I'm in the process of building a RPC and I'll post info once I complete it. I designed mine for a 10 hp idler motor and I am using a 60 amp breaker to feed it and 48 amp over loads on the three phase legs (IIRC - I'll check schematic later). Regarding your question about the phase converter: If it is a rotary phase converter, then you can virtually run as many machines from it as you like. A 10 horse RPC allows you to start a 7-10 horse motor but once that one is running, you can keep turning on more and more motors - each additional motor improves the efficieny of your RPC.

flylo
05-30-2012, 11:34 AM
I have a 10HP RPC & it runs everything I need.Also have a 460V transformer. Works very well. I picked a pair of new 40HP motors & am having one turned into a RPC.


My biggest current draw would be my welder. At full output (400 amps and roughly 53 OCV) it draws about 120 amps on 220V. It's very rare that I have the beast turned up to 400 amps. I don't think I ever will now that it is in a garage. Nothing that needs 400 amps will fit in the garage ... :p

Anyway, 200 amps should be plenty. I'm in the process of building a RPC and I'll post info once I complete it. I designed mine for a 10 hp idler motor and I am using a 60 amp breaker to feed it and 48 amp over loads on the three phase legs (IIRC - I'll check schematic later). Regarding your question about the phase converter: If it is a rotary phase converter, then you can virtually run as many machines from it as you like. A 10 horse RPC allows you to start a 7-10 horse motor but once that one is running, you can keep turning on more and more motors - each additional motor improves the efficieny of your RPC.

Tamper84
05-30-2012, 01:57 PM
Again thank you all!!! Can't wait to get started on this. I definitely need to research 3 phase converters. I don't if I should just leave a circuit open for it and just run 3 phase stuff off of that circuit or not. But anyway thanks for all of the info guys!
Thanks,
Chris

lakeside53
05-30-2012, 02:01 PM
Yes, you should have a separately brakered circuit for the rpc.

When you put in your panel, leave access above and below it (or just surface mount it). Adding a circuit is a simple as adding a breaker. As your hobby grows, you'll be changing the shop electrical many times.

Fasttrack
05-30-2012, 02:32 PM
What Lakeside said!


Regarding your phase converter, you can go with a static or rotary one. The static phase converters are cheaper to buy and simpler to build, but they require you to derate your motor and I've heard various complaints about them. Personally, it's a no-brainer - I chose to build a rotary phase converter.

Below are links to three different designs and some general reading to get you started. You'll need a large 3 phase motor and then start capacitors, run capacitors, relays/contactors, overloads, push buttons and an enclosure. The capacitors will be big so you need a big enclosure. Below is the one I bought a couple of years ago. I've been very happy with it.

http://www.ebay.com/itm/Electrical-Enclosure-Cabinet-Alarm-UPS-Locking-Box-New-/400265126593?pt=BI_Electrical_Equipment_Tools&hash=item5d31a922c1

You can get components here for cheap:
https://www.surpluscenter.com/electric.asp?catname=electric
(capacitors are listed under the red "Misc", then there are categories for "Switches" and "Relays/Contactors")

Designs:
http://www.practicalmachinist.com/FitchWConverter.pdf

http://www.metalwebnews.com/howto/ph-conv/ph-conv.html

http://www.homemetalshopclub.org/projects/phconv/phconv.html

lane
05-30-2012, 08:24 PM
First off ,Put in more than you need . What you have now Will be replaced as time goes on. .Yes I know . Started with a South Bend Lathe and a Rockwell mill . Now a 13x40 lathe still the SB Bridgeport type mill KO Lee surface grinder and a Tool and cutter grinder Had a Van Norman mill now a big shaper . You cant put in to much 220 You will need it later and wire is cheap . Wire for the future not the present . I did not and has been a big problem over the years.

legendboy
05-30-2012, 08:56 PM
I wish I had 200 amp service in my garage. I think my house is only 100 lol

CCWKen
05-30-2012, 09:59 PM
The service for the shop is split at the meter. One line goin to the shop and the other to the house. And the only thing I can think of that would be running 220 at the same time would the compressor and maybe something else.
That's not 200A service if you're sharing it with your house. The something else is the house. :rolleyes: Not a good idea if you plan on making use of anything near 100A total for the shop. A modern house can draw over 100A easily--Especially if it's all electric. :eek:

Tamper84
05-30-2012, 11:25 PM
That's not 200A service if you're sharing it with your house. The something else is the house. :rolleyes: Not a good idea if you plan on making use of anything near 100A total for the shop. A modern house can draw over 100A easily--Especially if it's all electric. :eek:

It is seprate. I have 100 amp in the house and 65 right now in the shop. I have been talking to the power co. They need to come and run a different line from the transformer to the meter. The meter is hanging off of of the shop. One line goes into the shop and the other to house. I could be wrong, but that is the way it was explained to me.

Thanks for the links for the phase converters! I have some more reading to do!!
Thanks,
Chris

Tamper84
06-19-2012, 08:04 PM
Sorry to bring up a dead thread here guys but same topic. Would you all run 10-3 or 10-2 for the 220 in your shop?
Thanks,
Chris

darryl
06-19-2012, 09:03 PM
10-3 with a ground- four wires in all. If you only run 10-2, then you have no safe way to derive 110 from it. You'd have to use the ground wire as the neutral, which works but is a no-no.

Rosco-P
06-19-2012, 09:44 PM
10-3 with a ground- four wires in all. If you only run 10-2, then you have no safe way to derive 110 from it. You'd have to use the ground wire as the neutral, which works but is a no-no.

Not exactly true. If the machine only requires 220vac (motors, pumps, etc.), no need for a neutral. If you need low voltage for other purposes (contactor coils, machine light, coolant pump), add a control transformer with a 220vac primary. If you find you need 110vac for something later you can add a step down transformer and bond one side of the output to ground so it doesn't "float".

RancherBill
06-21-2012, 12:34 PM
Sorry to bring up a dead thread here guys but same topic. Would you all run 10-3 or 10-2 for the 220 in your shop?
Thanks,
Chris

Assuming your shop is garage size, 14-2(15amp) or 12-2(20amp) for all the 110v circuits and ?-2 for the 220 circuits.