TS draw amps etc

[Craig D Peltier]

Hi this week im about to drop a 220 volt circuit into my garage for a future Table saw, this is down the road a year not sure of which one. I have the electrician doing it for free so I was wondering what the larger 3hp an even 5 hp saws you'll use are drawing for power in amps?
I was thinking of installing a 50amp breaker but that may be the wrong one to have installed. A 30 might be better suited.

Thanks

[Steven Wilson]

Table saw, then you'll have a DC, jointer, planer, shaper, thickness sander, and air compressor running on 220. Install a good sub-panel in your garage with as large of a circuit as you can readily support (say 50A, 60A, or 100A). Then wire up the individual machine circuits when you need them.

[Jim Becker]

You should be fine with a 30 amp circuit for almost any single phase saw you'll likely buy. That's what my MiniMax S315WS requires for it's almost 5hp motor and 1.5hp scoring motor combined.

[Craig D Peltier]

You should be fine with a 30 amp circuit for almost any single phase saw you'll likely buy. That's what my MiniMax S315WS requires for it's almost 5hp motor and 1.5hp scoring motor combined.
Thanks Jim, thats what I needed to know.

[Craig D Peltier]

Table saw, then you'll have a DC, jointer, planer, shaper, thickness sander, and air compressor running on 220. Install a good sub-panel in your garage with as large of a circuit as you can readily support (say 50A, 60A, or 100A). Then wire up the individual machine circuits when you need them.

I have a jointer running on 220 already, its a garage so there will be no 220 planer or sander in here. I just needed info on a TS , I will be upgrading this from my ridgid 3650.
Thanks

[Jim Newman]

Craig, I put in a 30 amp 220 volt circuit with 10 gauge romex wire with ground for my table saw. It was a 50 foot run from the circuit box to my shop outlet as well. I have never had a problem at start up, when you draw 2-3 times the normal amperage of normal running draw. My TS is a General 350 with a 3 HP motor, single phase. I was told this was the proper setup from Wilke Machinery where I bought my TS from. Hope it helps. Your application will depend on what HP and type motor is on your TS so good luck. My advice is do it right the first time instead of going too light and burning your motor out.

[Rick Christopherson]

A 3 hp tablesaw could be run from as low as a 15 amp circuit, but I would not recommend it unless there was the need to use an existing circuit (not applicable to your situation). If you knew that you were going to buy a 3 or even 4 hp tablesaw, then a 20 amp circuit would be sufficient.

Because you don't know what you might buy yet, this could be a case where installing #10 wire might be a good idea. Even though a garage workshop has little need for a 5 hp tablesaw, you might stumble across a good deal on a used saw between now and the time you buy. However, if you know in advance that you are going to buy a New saw, versus buying a Used saw, (some people always want new) then there is virtually no reason to expect needing a 5 hp saw.

Oh, I forgot that you mentioned a 50 amp circuit. That would be equivalent to a 10 hp motor (taking into account powerfactor and efficiency), and you are not going to fit a 10 hp tablesaw into a garage. The only reason for ever installing a circuit that large in a garage is if you think you might get a welder some day. More importantly, you would never be able to fit that large of a conductor into an outlet that wasn't rated for 40/50 amps (assuming you undersized the breaker). If you didn't undersize the breaker, then NEC requires you to use either a 40-amp or 50-amp outlet on a 50-amp circuit.

Also on that note, if you install #10 wire, you can still use a 20-amp breaker and 15 or 20 amp outlets. However, if you install a 30-amp breaker, then you are required to use 30-amp outlets (20-amp outlets are not permitted).

[Ken Fitzgerald]

IF I might make a suggestion....wire your 240 circuits as Rick suggested with 10 gauge. I started my shop 3 years ago and am just now finishing and "tooling" it. I work with electronics everyday and decided to overwire my circuits. My MM-16 4.8hp b/s arrived last week. If I hadn't overwired it, I'd be ripping walls out to replace 12 gauge with 10 gauge. I wired my 120 circuits with 12 gauge copper and my 220 with 10 gauge copper just in case............I sure am glad I did! I never thought I'd need a 30 amp circuit but just in case............

[Craig D Peltier]

A 3 hp tablesaw could be run from as low as a 15 amp circuit, but I would not recommend it unless there was the need to use an existing circuit (not applicable to your situation). If you knew that you were going to buy a 3 or even 4 hp tablesaw, then a 20 amp circuit would be sufficient.

Because you don't know what you might buy yet, this could be a case where installing #10 wire might be a good idea. Even though a garage workshop has little need for a 5 hp tablesaw, you might stumble across a good deal on a used saw between now and the time you buy. However, if you know in advance that you are going to buy a New saw, versus buying a Used saw, (some people always want new) then there is virtually no reason to expect needing a 5 hp saw.

Oh, I forgot that you mentioned a 50 amp circuit. That would be equivalent to a 10 hp motor (taking into account powerfactor and efficiency), and you are not going to fit a 10 hp tablesaw into a garage. The only reason for ever installing a circuit that large in a garage is if you think you might get a welder some day. More importantly, you would never be able to fit that large of a conductor into an outlet that wasn't rated for 40/50 amps (assuming you undersized the breaker). If you didn't undersize the breaker, then NEC requires you to use either a 40-amp or 50-amp outlet on a 50-amp circuit.

Also on that note, if you install #10 wire, you can still use a 20-amp breaker and 15 or 20 amp outlets. However, if you install a 30-amp breaker, then you are required to use 30-amp outlets (20-amp outlets are not permitted).

Thanks Rick and everyone else. Im going to return my 50 amp today and get a 30 amp breaker and a proper plug for the heater im going to plug into it for now. I will keep in mind the 10 gauge wire also. So if you use 12 gauge an I have a 3hp TS then it may burn out the motor after extended use.Is this correct?
Thanks

[Rick Christopherson]

Thanks Rick and everyone else. Im going to return my 50 amp today and get a 30 amp breaker and a proper plug for the heater im going to plug into it for now. I will keep in mind the 10 gauge wire also. So if you use 12 gauge an I have a 3hp TS then it may burn out the motor after extended use.Is this correct?
ThanksI am not sure I am reading this correctly, but it kind of sounds like you are planning on using a 30-amp breaker on #12 wire. This is not something you can do. As I mentioned above, you can do the reverse of this and put a 20-amp breaker on #10 wire, but you cannot put a 30-amp breaker on #12 wire.

So if you use 12 gauge an I have a 3hp TS then it may burn out the motor after extended use.Is this correct?Given this question, I am starting to think that you might have your wire sizes confused. The smaller the wire gauge number, the larger the wire diameter. #12 is for 20 amps, and #10 is for 30 amps.

As for my "assumed" intent of your question, no, you will not damage a 3 hp saw on a 30-amp circuit. The circuit breaker is not intended to protect the tool, only the wiring within the house. The tool will have its own overload protected specifically geared toward the tool itself. Technically, if the motor did stall and it did not have its own internal overload protection, then even a 20-amp circuit would permit the windings to be damaged.

[Craig D Peltier]

I am not sure I am reading this correctly, but it kind of sounds like you are planning on using a 30-amp breaker on #12 wire. This is not something you can do. As I mentioned above, you can do the reverse of this and put a 20-amp breaker on #10 wire, but you cannot put a 30-amp breaker on #12 wire.
Given this question, I am starting to think that you might have your wire sizes confused. The smaller the wire gauge number, the larger the wire diameter. #12 is for 20 amps, and #10 is for 30 amps.

As for my "assumed" intent of your question, no, you will not damage a 3 hp saw on a 30-amp circuit. The circuit breaker is not intended to protect the tool, only the wiring within the house. The tool will have its own overload protected specifically geared toward the tool itself. Technically, if the motor did stall and it did not have its own internal overload protection, then even a 20-amp circuit would permit the windings to be damaged.

Thanks Rick, I just bought some 10 gauge for a 30 amp breaker double pull and it will go to a 240volt outlet that for now will run a heater but in future I can change the plug and run the TS.

[Randall Davis]

A 3 hp tablesaw could be run from as low as a 15 amp circuit, but I would not recommend it unless there was the need to use an existing circuit (not applicable to your situation). If you knew that you were going to buy a 3 or even 4 hp tablesaw, then a 20 amp circuit would be sufficient.

Because you don't know what you might buy yet, this could be a case where installing #10 wire might be a good idea. Even though a garage workshop has little need for a 5 hp tablesaw, you might stumble across a good deal on a used saw between now and the time you buy. However, if you know in advance that you are going to buy a New saw, versus buying a Used saw, (some people always want new) then there is virtually no reason to expect needing a 5 hp saw.

Oh, I forgot that you mentioned a 50 amp circuit. That would be equivalent to a 10 hp motor (taking into account powerfactor and efficiency), and you are not going to fit a 10 hp tablesaw into a garage. The only reason for ever installing a circuit that large in a garage is if you think you might get a welder some day. More importantly, you would never be able to fit that large of a conductor into an outlet that wasn't rated for 40/50 amps (assuming you undersized the breaker). If you didn't undersize the breaker, then NEC requires you to use either a 40-amp or 50-amp outlet on a 50-amp circuit.

Also on that note, if you install #10 wire, you can still use a 20-amp breaker and 15 or 20 amp outlets. However, if you install a 30-amp breaker, then you are required to use 30-amp outlets (20-amp outlets are not permitted).

Safe! not required!

[Rod Sheridan]

Hi, my 3 HP saw (General 650) has a 12.4 ampere full load current.

I run it from a 15 ampere circuit.

A 20 ampere circuit would be adequate for any 3 HP of lower power factor and efficiency.

Regards, Rod.

P.S. The most current I've ever used is ripping 8/4 white oak, and it was 10.4 amperes.

[David G Baker]

I would go for the #10 wire.

[Jim Newman]

Problem is not during actual running of the saw or other equipment, but during startup when the motor can pull 2 to 3 times normal amperage draw. That is why I put in a 30 amp circuit with 10 gauge wire. Also I had a longer run from the breaker box (about 50') and the fact it is easier on the motor. This is one area you get what you pay for. Is it theoretically possible to run a TS on a 15 amp circuit? Absolutely, but there is always a price to pay in terms of strain on the motor and more resistance to the flow of electricity, more heat generated on the circuit and wires in the wall, plus a potential trip to the circuit breaker box.

[Jude Tuliszewski]

A good place to read about electrical stuff is at mikeholt.com , but do it when you have some time on your hands. The first time I did seemed like I was there a half hour but 3 hour had flown by :eek: .

OOOPS, sorry bout the link, I forgot that direct links were a No No.

[Richard Alexander]

Table saw, then you'll have a DC, jointer, planer, shaper, thickness sander, and air compressor running on 220. Install a good sub-panel in your garage with as large of a circuit as you can readily support (say 50A, 60A, or 100A). Then wire up the individual machine circuits when you need them.

How can you tell how large of a circuit your panel can support? I'm about to install a 220 circuit for a new TS and I never considered a sub-panel until reading this. What are the benefits of a sub-panel? Just more circuit "ports"?

Also, if I'm not getting too off topic, does each machine need its own circuit run from the breaker box or can more than one run off the same circuit? I'm looking into buying a jointer in the next year and want to take care of any wiring now. For what its worth, I tried hiring an electrician and had two no shows, no calls. I was considering tackling this anyway which is what brought me here.

[Rod Sheridan]

Hi Richard, there will be two issues that determine the maximum capacity of the breaker you use to feed a sub panel.

1) The maximum size of breaker that your main panel can accept.

2) The capacity of your service, service panel, and existing house load.

As to running more than one machine from one circuit, no problem as long as you only use one machine, and the cyclone at a time.

My shop use a 15 ampere 240 volt feed for all the 240 volt machines including 3 HP tabesaw, 3 HP shaper, 3 HP planer, 2 HP bandsaw etc. The same feeder also supplies 15 ampere 120 volt split receptacles.

(The 240 duplex receptacle and the 120 V duplex receptacles are in a 4 inch square box, which is very convenoent. Every box has 240 and 120 V receptacles.)

A second 15 ampere circuit feeds the 1.5 HP oneida cyclone.

That's it, quantity 2 15 ampere 2 pole breakers run all the shop equipment, as long as I only want to run one machine at a time.

A dedicated 15 A 1 pole breaker runs all my lights except for one, which was on an existing circuit, and gives some lighting redundancy.

Note that my shaper, tablesaw and planer have high efficiency, high power factor motors which draw a maximum of 12.4 amperes at rated load. A less efficient, lower power factor motor will draw more current.

You'll have to check your machinery for nameplate information. In the event that your motor is 16 amperes or less, you could use a 20 Ampere breaker, 20 A 240 V receptacles, and 20A 120 V "T slot" receptacles.

In my case a 60 ampere sub panel was more than adequate, however so would running 3 circuits be adequate, it just depends upon the layout and your preferences.

Regards, Rod.

[Steven Wilson]

Richard, you'll need to consult the NEC and your local inspector as to sizing. Having an electrician wire up a subpanel is a pretty good idea. Now, once you have a subpanel in your shop you have the following features.

1) The ability to expand branch circuits when you need to without running wires all the way to your main panel.

2) A disconnect (breaker)

3) If you also wire up a disconnect with a lockout you then have a secure way of shutting off all the power to your machines.

4) Easy access to the breakers if you trip a circuit.

5) If you overload your sub panel you'll just trip that breaker, but you'll still have the rest of your main panel circuits working (say you trip your sub panel with too many machines turned on - you'll still have your lights).

As for each machine needing it's own circuit the answer is no. Each branch circuit needs its own circuit (bad pun). I have a 50A sub panel. In the sub I have 3 branch circuits; 2 20A 220V, 1 30A 220V. One of the 20A circuits services the DC, the 30A services my Euro combination machine and bandsaw (all 4.8hp motors), and the other 20A circuit services my lathe and some other machines.

[Rick Christopherson]

I'm about to install a 220 circuit for a new TS and I never considered a sub-panel until reading this. What are the benefits of a sub-panel? Just more circuit "ports"? With the way you asked this question, it makes me believe that you might have been thinking in the back of your mind that a subpanel might give you more power. If so, the answer to that is no, it will not give you any additional power than what you already have in the main load center. The second part of your question is correct; the benefit of a subpanel is to give you more circuit breaker locations when your main load center is already full.

You got two semi-conflicting answers regarding multiple outlets on the same 240 volt circuit. Both answers were correct in telling you that you can put multiple outlets on the same 240 volt circuit. The NEC does not make any distinction between 120 volts and 240 volts. Rod’s explanation was based on his particular setup, and from that perspective is correct, however, there is nothing preventing you from running multiple machines at the same time as long as you don’t exceed the amperage of the circuit. For multiple outlet circuits, I would not use anything less than 20 amps unless it was known that the loads were small enough to not total more than 15 amps for all tools running simultaneously.

Installing your own circuits is not that difficult. If you are not familiar with installing any wiring, you should first check with your local permitting authority to see if a homeowner is permitted to do their own wiring. Some do, and some don’t. If yours does permit it, then you should pull a permit, and could also ask your inspector for any specific tips about installing the circuit(s). The benefit to pulling the permit is that you can have the work inspected to ensure it is completed correctly.