Friday, 11 August 2023

Re: [atlas-craftsman IO] OT-how to test and repair DC brushed motors.

        Just tossin this out there , with no load on the motor you will not get the actual amp reading . Also unless  you have a good DC clamp meter most DVM that do amps top out at 10 amps .

       I thought there was a guy in this group that had a motor shop ?  Does the motor absolutely have to have the right angle gear box or can it be a straight gear reduction motor ?

        animal

On 8/11/23 9:02 AM, Bill in OKC too via groups.io wrote:
SWMBO' s power wheelchair lift crapped out the other day. New motor is no longer available since the lift is ancient. Manufacturer of the lift removed any OEM markings. It's a right- angle gear motor, which I'll eventually have some photos and dimensions for. This is the in-and-out motor for a Harmar AL-600 lift that fits in the back of a van. Near as I can remember it was made about 2007 or so. 

There is no continuity in the motor, but  othinf seems burned. I pulled it apart and fiddled with it, and got continuity back. Hooked it back up to power trying to get a current draw reading and it spun up and  rapped out again. No continuity again. Brushes look good. 

I have a megger for testing  insulation, and an assortment of DVMs and at least one analog voltmeter. Somewhere in the library are a couple of older books on motor testing and repair, but haven't found them yet. Any suggestions for resources? I looked at Grainger & McMaster-Carr, also Amazon & Surplus Center. They have similar gear motors but nothing that looks exactly  right. Most are either way too light or way too heavy. This is a 12vdc motor, could draw as much as 20amps, but probably closer to 10, and could less. There is another motor on it with a different gearbox. Looks to be about the same motor. May fiddle with that, and get a current draw.

Found one of these motors for sale on the knoppix site for $600, was $400 from Harmar at one time. Seems a bit fishy to me, and can't afford it anyway. 

Gotta get ready to take SWMBO to get fitted for a new CPAP mask, and for both of us to get new CPAP machines. Hope someone can point me in a useful direction. Used to be a bunch of folks whe rebuilt motors & alternators/generators around here. Called one and they don't do DC motors at all, and don't think there's anyone left who does.,

Any help will be appreciated!


Bill in OKC 
_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

View/Reply Online (#115920) | Reply To Group | Reply To Sender | Mute This Topic | New Topic
Your Subscription | Contact Group Owner | Unsubscribe [jhjoshan@gmail.com]

_._,_._,_

No comments:

Post a Comment