When I replace garbage disposals, I prefer to use a power cord rather than hardwire them straight into the wall. The thing is, I don’t like paying $12 for the official power cord, which is chintzy looking and, frankly, looks under spec’ed. Instead, I prefer to use a computer power cord on a garbage disposal.
The label on a 1/3 HP Insinkerator Badger says it’s rated for 5.8 amps at 125 volts. I found a computer power cord in my stash that was rated for 10 amps at 125 volts. It’s overkill, but when it comes to electricity, overkill is good. Best of all, it let me repurpose something I’d already paid for and was probably never going to use.
Be aware that if you use your own power cord, you’ll also have to provide a 3/8-inch electrical cable clamp connector. Insinkerators and their house-brand cousins don’t come with the clamp. You can find them in any hardware or home improvement store in the electrical aisle, near where the metal conduit and fittings are. A bag of five costs less than $2 if you can’t buy a single. They’re the same connectors you use in junction boxes, so having four extras around isn’t a bad thing.
The connector screws into the bottom of the unit. There’s no need to use the nut that comes with it. It won’t hurt anything if you do, but it’s one more tedious thing you have to do.
Resist the temptation to skip the connector. The hole the power cable runs through is sharp enough to cut Romex cable, and I’ve seen it happen. If it cuts through the insulation of the black wire, you’ll have a short, and you’ll either end up with an unhappy breaker box, or an electrified case, depending on whether the green wire also got cut. An electrified case for something that normally has water flowing through it is a bad thing.
As far as adapting the computer cable, there’s not much to it. My unused desktop computer power cable had a tag on it with a voltage and amperage rating on it. Many do. As long as it’s more than the amperage requirements printed on the disposal, you’re golden. If it’s less, find another cable, or if you can’t, buy a grounded extension cord of the proper rating–a 15-amp 3-prong extension cord costs about $4.
Measure the distance you need, then add about four inches of slack to it. Cut the cable to length, leaving the three-prong connector on one end and bare wire on the other. Cut back the black jacket a good two inches. Next, strip back the black, white, and green wires about a half inch. Remove the cover plate on the bottom of the unit. Thread the bare end of the cable through the cable connector. Attach the cable’s black wire to the disposal’s black wire, the cable’s white wire to the disposal’s white wire, and attach the green wire to the screw on the case.
I use the small blue wire nuts to do the attachment, then wrap a piece of electrical tape around the end to hold the wire nut in place and give a little more insulation and protection. I’ve seen people use the monster red wire nuts and stuff them in. That makes it harder to reuse the power cord the next time you replace the disposal, and may displace some of the shielding. Don’t make it any harder on yourself than you need to.
Why do I prefer to plug a disposal in rather than hardwire it? It allows me to unplug the disposal to disable it. That beats having to run to the breaker box in the basement, seemingly always on the side of the basement furthest from the kitchen. Hopefully the breaker for the disposal is labeled, but often it’s not. If I need to reach into the disposal to retrieve something, it’s much more convenient to be able to just open up the cabinet and pull the plug on it. Just check with your local municipality to make sure it’s OK to have the disposal plugged in rather than hardwired. Local codes may vary.
I hope you’ve found this post helpful, and that it saves you a few dollars. If you have, please share a link, whether it’s on your own blog, a forum, Twitter, or a site like Facebook.