Problem rewiring RAS to 220

[Matt Day]

I want to rewire my Dewalt/B&D RAS from 110 to 220 since it seems to lack power, likely because I also have my DC running on the same circuit when I use the saw.

I rewired the saw exactly as the motor cover said, and the first time I tested it it fired up, worked great and sounded good. I finished up the electrical work and closed everything up, and then after trying it again all I got was a loud buzzing noise (same noise it makes just as it starts spinning the blade) and no blade movement.

Any idea what it could be? I've attached a picture of the capacitor which looks fine, but I did notice it seems to be labeled 110, but I'm not certain I'm reading it correctly.

The saw is a Dewalt 7790.

[Dick Reeves]

Matt:
You will probably need to get a new capacitor rated 220v. Your best bet is to write down all the electrical specifications of the motor; horsepower, amperage etc. and go to a motor repair shop so they can match up a capacitor suitable to your application. Might not hurt to draw a diagram of your wiring just in case there are any questions.

Another suggestion is that you may want to check the voltage at the panel from which this circuit is fed and also at the saw outlet and at the DC location to make sure you don't have too much of a voltage drop. Checking the voltage while the equipment is running wouldn't hurt either.

Good luck. Doesn't seem like you have a big problem and the new capacitor should be relatively cheap.

Dick Reeves

[Charles Lent]

Disturbing the wiring to change the voltage may have caused one of the wires to come loose, or it may have caused the centrifugal start switch that's inside the end of the motor to malfunction. It's contacts should be closed when the motor is at rest, and open as the motor reaches about 1/2 of it's speed. Centrifugal weights and springs around the motor shaft move a plastic collar on the motor shaft that presses against the centrifugal switch to operate it. Check the wiring again to be sure everything is connected and then check the centrifugal switch for correct function. The capacitor, centrifugal switch and the start winding of the motor should all be connected in series.

Charley

[Rod Sheridan]

Hi, Charles has the most probable cause, a wire came loose when you packed everything back in the box.

Your start capacitor is the correct voltage, it only sees 120 volts regardless of whether the saw is configured for 120 or 240 volts, no need to change it.........Rod.

[Rich Tomassetti]

I want to rewire my Dewalt/B&D RAS from 110 to 220 since it seems to lack power, likely because I also have my DC running on the same circuit when I use the saw.

I rewired the saw exactly as the motor cover said, and the first time I tested it it fired up, worked great and sounded good. I finished up the electrical work and closed everything up, and then after trying it again all I got was a loud buzzing noise (same noise it makes just as it starts spinning the blade) and no blade movement.

Any idea what it could be? I've attached a picture of the capacitor which looks fine, but I did notice it seems to be labeled 110, but I'm not certain I'm reading it correctly.

The saw is a Dewalt 7790.

Matt, Go here--all about DeWalt radial arm saws. Enjoy "DeWalt" Radial Arm Saw Forum (http://forums.delphiforums.com/n/main.asp?webtag=woodbutcher&nav=messages&start=Start+Reading+>>&lgnJR=1&prettyurl=%2Fwoodbutcher%2Fmessages%2F%3Fstart%3DS tart%2BReading%2B%3E%3E%26lgnJR%3D1)

[Matt Day]

Well I took the relay out and checked it out (read: played with it and didn't really do anything), removed the switch and checked the wiring, and plugged it back in. I'm not sure what did it, but it started right up and purrs. I'm glad to have it working but I wish I knew what the problem was. Thanks for the advice in any case!

[Matt Day]

Matt, Go here--all about DeWalt radial arm saws. Enjoy "DeWalt" Radial Arm Saw Forum (http://forums.delphiforums.com/n/main.asp?webtag=woodbutcher&nav=messages&start=Start+Reading+>>&lgnJR=1&prettyurl=%2Fwoodbutcher%2Fmessages%2F%3Fstart%3DS tart%2BReading%2B%3E%3E%26lgnJR%3D1)
I actually posted there too! Similar advice to what I got here. Thanks!