8" jointer electrical requirments

[JLYoung]

This past weekend at the Moncton, NB woodworking show I bought an 8" Steel city jointer with Granite fence and tables. Now I need a place to plug it in in my basement. The jointer runs on 240V power and the manual says the motor draws 7.5 amps. It has a plug with two horizontal prongs and a grounding pin which I beleive is rated at 15 amps. I intend to install a 15 amp double pole square D breaker, 12/2 wire running about 75 feet and the 15 amp rated 240 volt receptacle. Is this adequate for the machine?

[BenMinshall]

This past weekend at the Moncton, NB woodworking show I bought an 8" Steel city jointer with Granite fence and tables. Now I need a place to plug it in in my basement. The jointer runs on 240V power and the manual says the motor draws 7.5 amps. It has a plug with two horizontal prongs and a grounding pin which I beleive is rated at 15 amps. I intend to install a 15 amp double pole square D breaker, 12/2 wire running about 75 feet and the 15 amp rated 240 volt receptacle. Is this adequate for the machine?

Yes that's an appropriate sized circuit for that machine. Take note that you'll want to make sure the NM-B cable is protected from damage by running it through the joist spaces in the ceiling and sleeving it in conduit down the walls; NM cannot run on exposed on the face of framing or finished walls. You could use a 20A breaker and a 6-20R t-slot receptacle for future compatibility with both 15A and 20A machines.

It sounds like a great jointer. What do you think of the granite tables instead of cast iron?

[JLYoung]

Yes that's an appropriate sized circuit for that machine. Take note that you'll want to make sure the NM-B cable is protected from damage by running it through the joist spaces in the ceiling and sleeving it in conduit down the walls; NM cannot run on exposed on the face of framing or finished walls. You could use a 20A breaker and a 6-20R t-slot receptacle for future compatibility with both 15A and 20A machines.

It sounds like a great jointer. What do you think of the granite tables instead of cast iron?

[JLYoung]

Thanks Ben,

The shop right now is unfinished but the room adjacent to it (which separates the shop from the electrical panel) is. Thankfully I had the forseight to pre-bore the holes through the joists and install some fish lines to run the wire before I hung the drywall. So there's no need to use metal conduit.

I have considered using a 20 amp breaker and plug just to make sure the breaker doesn't trip if the motor draws more than the rated 7.5 amps during start up or a deep cut. I think I probably will upgrade to 20 amp. Will the 12/2 wire still be adequate?

As far as the jointer goes, I'm still waiting for it to arrive. I had a good look at the machine at the show and if there's any tool where granite would not be a drawback it would be a jointer. Nice flat, stable reference surface. The one thing I did notice is that on the infeed and outfeed tables, right next to the blade, Steel City has mounted an aluminum plate. The sales guy tells me that if I ever hit aloose know or something, it could chip the granite at this location. That's why they've installed the aluminum plates. The only issue I can see with this is that this creates another place that has to be accurately adjusted so that the wood doesn't catch on the edge of the plate and /or create snipe. thankfully, I see that SCTW has added set screws at each of the four corners of the plates for fine adjustment. Time will tell...

[Beechwood Chip]

I only use 15 amp circuits for lighting; I make all circuits with outlets 20 amp. I figure that I may want to plug in a 20 amp appliance / tool / whatever, down the line.

I use 12 gauge for 20 amp and 14 gauge for 15 amp, but you should triple check that.

[BenMinshall]

I have considered using a 20 amp breaker and plug just to make sure the breaker doesn't trip if the motor draws more than the rated 7.5 amps during start up or a deep cut. I think I probably will upgrade to 20 amp. Will the 12/2 wire still be adequate?

Yep, max breaker is 20A for #12 wire or 15A for #14 wire up to at least 100' of cable; longer than that you would want to consider one size larger of wire. You don't really need to upsize the breaker as pretty much all modern breakers have an HACR rating so they should handle start-up surge for most common types of motors. There's really no harm in using a 15A or 20A breaker, but the 20A would give you a little leeway for larger tools in the future or to run two 240V tools at the same time.

As far as the jointer goes

Sounds like a nice machine. I'll be looking for the trip report once you get it in the shop and set up!

[Mike M]

Totally agree. I wouldn't bother wiring a 15 amp circuit in my shop except for lighting. Wiring with 12 gauge instead of 14 gauge is a bit more difficult and costs a few pennies more, but if your tool trips the breaker every time you start it up, it becomes a royal pain. Spend the extra pennies and wire 20 amp circuits for both your 110 and 220 runs (unless you have a 5hp tool that takes 30 amps).