gdgarris
Plastic
- Joined
- May 19, 2012
- Location
- Raleigh, NC, USA
Hey everyone,
I'm new here (first post), so I'm hoping I put this thread in the right place...
I have an old Craftsman bench grinder and she seems to have given up the ghost. My father gave it to me, so I'd like to see it turn again. Its stamed Nov. 28 1968 on the baseplate and according to the faceplate it is a 1/3 horse motor that draws 3.5 amps at 115 volts. The wheels turn freely by hand, but under power it locks up and hums. It can still be turned by hand under power, but has considerably more resistance. From what I understand (which isn't much), these split phase motors are fairly simple. They consist of the motor itself, a starting relay, and a power switch. So, I've been trying to systematically determine where my trouble lies. I figure if I here a hum after flipping the switch, its getting power, so the switch is good. Then, I slapped a multimeter on the motor to check its resistance. My thinking is if I was getting next to no resistance, there may be a short somewhere in the windings. However, I'm getting something like 13 ohms. I didn't expect the resistance of a bunch of copper wire to be too high, so 13 ohms sounds reasonable to me. Also, if there was I short, I would expect the breaker to trip (which wasn't happening). So, this is telling me that it is the relay.
I've got a couple question for all of you. Is there any good method of testing a relay? If it turns out to be faulty, what are some viable replacements? I can imaging finding this specific of a relay (a Klixon 2CR-14-224) could cost me a pretty penny (probably more than a new grinder) so would there be some sort of generic replacement I could slap in there? Can you think of anything I am forgetting to test?
I appreciate the help in advance. I figure if anybody will know how to get it turning again, I'll be one of you. I've attached (hopefully) a few pictures below to give you a better idea what I'm taking about.
-Dale
I'm new here (first post), so I'm hoping I put this thread in the right place...
I have an old Craftsman bench grinder and she seems to have given up the ghost. My father gave it to me, so I'd like to see it turn again. Its stamed Nov. 28 1968 on the baseplate and according to the faceplate it is a 1/3 horse motor that draws 3.5 amps at 115 volts. The wheels turn freely by hand, but under power it locks up and hums. It can still be turned by hand under power, but has considerably more resistance. From what I understand (which isn't much), these split phase motors are fairly simple. They consist of the motor itself, a starting relay, and a power switch. So, I've been trying to systematically determine where my trouble lies. I figure if I here a hum after flipping the switch, its getting power, so the switch is good. Then, I slapped a multimeter on the motor to check its resistance. My thinking is if I was getting next to no resistance, there may be a short somewhere in the windings. However, I'm getting something like 13 ohms. I didn't expect the resistance of a bunch of copper wire to be too high, so 13 ohms sounds reasonable to me. Also, if there was I short, I would expect the breaker to trip (which wasn't happening). So, this is telling me that it is the relay.
I've got a couple question for all of you. Is there any good method of testing a relay? If it turns out to be faulty, what are some viable replacements? I can imaging finding this specific of a relay (a Klixon 2CR-14-224) could cost me a pretty penny (probably more than a new grinder) so would there be some sort of generic replacement I could slap in there? Can you think of anything I am forgetting to test?
I appreciate the help in advance. I figure if anybody will know how to get it turning again, I'll be one of you. I've attached (hopefully) a few pictures below to give you a better idea what I'm taking about.
-Dale