Hi Everybody,
I think I know the answer, but I’m wondering if I can get away with this safely for a period of a few months…
I’ve moved into a new house and have an old Powermatic contractors table-saw (Powermatic 63, “Artisan” – nothing to write home about unless it’s to complain) which trips the 15A breaker currently on this circut to my garage about 60% of the time on start-up. I lined up my friendly neighborhood electrician to wire me a subpanel to the garage and help me run some proper 20A circuts out there. In the planning phases it became clear that that was not a real viable option given the fact that my main panel is completely full. So, we are planning on adding a second main panel next to the original and then from there running the sub-panel out to the garage. BUT, that costs considerably more moo-lah than I originally budgeted for and it will take me a few months of saving to come up with the scratch.
In the meantime my salty old neighbor, retired marine corps officer type, said I should just put in a 20A breaker on that circut. I know that’s probably not the “correct” answer, but can I get by with it? There are two or three interior overhead lights on the same circut that are never on when I am in the garage working with the tablesaw, and two outdoor outlets that are also unused when I am working. Also, the current breaker is a piggy-back 15A so the second breaker switch does control a lighting/receptical circut that is often in use. I think that last bit is the kicker.
I know this can’t be a great long-term solution or my electrician would have suggested it, but can it be safe for a bit? Thanks for all of your help, I’m awaiting my lambasteing… 😉
Erich
Replies
It might just be that the breaker is a little "weak" and trips too easy. Try the saw on other 15A circuits to see if you have the same problem. If not, replacing only that breaker is a safe and easy fix - and easier one is to just run an extension cord to where it doesn't trip the breaker!
If it trips other 15A circuits... do you have any 20A circuits at all? I had a problem running air compressors in my Garage with anything else running... then I found that my Microwave in the kitchen had a 20A outlet. Much to the annoyance of everyone in the house having to run an extension cord across the house.
The only way you could run a higher amp breaker on a thin line is for direct wire hookups on specialized motor devices. This is not that sitiation!
There are other things I can think of to get your saw working, but a 20A on a 15A circuit is not where to start.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
If your hair looks funny, it's because God likes to scratch his nuts. You nut, you.
Paul,
Thanks for the ideas, I think I will go that route and see what I can come up with. I was just coming back here to chide myself for admitting to thinking of doing what one electrical author termed the modern-day equivalent of sticking a penny in the fuse-box. I certainly don't want to over-heat the wire, melt the insulation, and burn down my house just so I can get my lousy table-saw working.
I'll check to see if I can plug it in somewhere else and if it works, bingo. Second, I have what looks to be a dedicated microwave outlet. That "should" be 20A, I'll try that. Of course, my main panel "shouldn't" be grossly undersized for my service but it is, so I can't count on whatever builder/electrician was trying to make a buck when they built this house, (for further evidence note that I have one, that's uno, receptical in the garage). I can't wait until I can live in a house I have built and wired/plumbed the way I'd like!
Anyway, thanks agan!
Erich
what about your chord between the wall and the saw motor? In the past I've beefed mine up (largest dia & shortest useful length) that the plug & motor would accept and gotten improvements (I think).
re: 20A power sources.
I always look to the laundry room in unknown houses. Many washing machines are plugged into a 20A line.
Jim Never underestimate the value of a sharp pencil or good light.
I know this can't be a great long-term solution or my electrician would have suggested it, but can it be safe for a bit?
Briefly, no. The electrical code is the code for a reason. It's a minimum safe standard.
What size is the motor on the saw? If it's 1 HP or less, it should run fine on a 15A circuit. If it doesn't, something is wrong with either the circuit or the saw.
If it's larger than 1 HP, MAYBE 1.5 HP tops, it needs a 20A circuit.
Changing your breaker to 20A with 14 guage wire will:
1. Eventually damage the saw's motor due to overheating
2. Cause the saw to be "sluggish".
3. Cause too much heating of the wire.
4. Very possibly start a fire.
What about getting an inexpensive generator to use to power the saw until you can have the proper circuits installed? I got a 20A generator on sale for $30 or so. Probably won't last forever, but it could be an option for a few months.
Can't you consolidate some of the circuits in your main panel using double breakers like this, and make room for a double-pole breaker for your garage subfeed panel?
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It might be fine, but you'll have a hard time getting someone to agree to it in writing in a public forum.
If you can really do without the other devices (lights, plugs, etc.) consider installing a 20A breaker which protects a heavy duty plug mounted under the panel. Then use a #12 or #10 extension cord from the plug to your saw.
Scott.
Always remember those first immortal words that Adam said to Eve, “You’d better stand back, I don’t know how big this thing’s going to get.”
I am surprised some of the regular gurus (I am not one)have not chimed in. I do not think I would run my Makita circ saw off a 14awg ckt unless very close to the panel. There are many variables, maybe I missed the distance but that sure is one. If a decicated ckt you can up the breaker for a motor type load to handle startup draw IIRC.
I would look at the tandem like River mentioned or a small subpanel.