here is the situation: i have a machine (Belco Glass model 7744-01010) that uses an electric motor (Bodine type 24Y0BEPM 115 volts Hz DC FF 1.4 A 0.25 HP 1/42) to rotate a plate which we put dishes full of solution on top of and it keeps them homogenously mixed as it rotates.
recently the device stopped rotating so i took it apart and the motor looked dirty and messed up and was hard to spin with my hand so i ordered a new one from the company. but when i installed the new motor the thing still wouldn’t spin. then i became suspicious of the circuit board as this machine is likely quite old and frequently gets spilled on so i got a multimeter and measured the current at the connection where the motor hooks to the circuit board and as i turn the potentiometer which controls the speed of the motor sure enough there is current flowing (0 at low end-110V at high end) but i have no idea how to proceed in getting this machine back in working order. what do you suggest?
can you spin the plate/turntable by hand with the motor out? if not, and as you say a lot of stuff has been spilled, it could be binding and the extra load might have been what killed the original motor.
if you don’t know about servicing electronics then don’t mess with that part of it, it is a hazard to yourself and the device.
an old machine in a wet environment will degrade. lubrication, if any, degrades. gears, bearings corrode and wear and no longer move smoothly. it may take a total dismantling and cleaning reconditioning.
but i’m trying to learn something here, people!
what i measured earlier was actually voltage. the thing is completely dismantled and i cleaned and lubricated everything that i haven’t replaced. please try to help me learn.
Since the motor was replaced then its probably the circuit board. These days its rare to try and fix circuit boards in the field. Typically you get a new one from the manufacturer. Are the wires going to the board plugged in or permanently attached? If the wires use connectors then it should be pretty easy to swap out the board.
Whether you can get a circuit board depends on the type of equipment. Consumer grade stuff is pretty much throw away and parts difficult to get. Commercial or industrial equipment is still usually serviced.
Did you measure the voltage with or without the motor connected? If without, with the the motor connected, it could drag the voltage down to where it won’t run.
Before you replace the whole board, try jumpering the pot. If that produces full speed, then the pot is bad, Work alikes , volts, amps, ohms should be easy to find.
Help from a professional would be good, but not sure what kind to suggest.
Note the capacitor checks suggested while I was posting sound good to me. Step one, short the terminals.
ETA²
Another thing you can do is take the black and white leads off the motor and put them in the appropriate slots in an extension cord and then plug the extension cord in. (we have nifty alligator clips that make this easy)
By applying 115V directly to the motor you can eliminate it (or identify it) as a/the problem.
You’re bypassing all of the controls and if the motor works correctly you can work upstream to the speed control, or the circuit board.
I don’t know this piece of equipment so this is a SWAG, but is the speed controller in the circuit board or outside of it?
Is the speed controller integrated into the controls, or is do you manually manipulate the potentiometer?
If the speed controller is outside the circuit board, you can troubleshoot the board simply by making sure its outputting 115V.
i know i can get another circuit board, but they are kinda pricey so i want to be sure that is the problem before i drop the cash on it.
where would the capacitor be that is SOP to replace? there are 7 on the board as far as i can tell.
i measured the voltage with the motor attached and the and it goes from 0.0 to 0.2V. and i have to turn the knob with my hand.
raindog i when i measure the voltage from the motor terminals on the board and turn the pot all the way up it shows 110-115 on my multimeter; doesn’t this mean the board is outputting 115V?
Motor capacitors usually are bigger than what you find on a circuit board and usually are connected to leads to the motors. The name plate on the motor or catalog description may say something about a capacitor. The rating should be part of the motor info somewhere.
Oh, I like the extension cord better than jumpering the pot. Truly competent people applaud better suggestions.
jdchurchill
I think it may be worthwhile to take a step back and do a reality check.
I applaud your gumption, but at this point you’ve already diagnosed a bad motor, and early evidence suggests that that was incorrect. You’re out the cost of a motor already.
Sometimes good money is chasing bad money. If there is a service agency in your area it may be cheaper to pay a professional than doubling down your bet with a new circuit board.
If you apply 115V and the motor won’t run, look for a capacitor.
If it still doesn’t run, apply 115V to the motor without the load. There might be something wrong with the load (the spinning wheel) that’s keeping the motor from spinning.
(and if you’re applying 115V to a bound up load, it won’t be long at all that you burn up the motor. Go slowly and be quick to disconnect voltage if you hear a motor groaning to start)
ok let me see if i can hit everyone’s concerns here: yes the turntable spins without the motor in, jz but i did have to lube up the bearings a little.
i did connect the old and new motors straight to power (through the machine’s leads bypassing the fuse and circuit board) and the new one spins but makes a buzzing noise and seems to take perhaps 3 seconds before hitting full speed. the old one just makes the buzzing noise and does not spin. so i guess i got that part right: that the motor was burned out.
there are many capacitors on the circuit board but only two are on a line of solder that connects to the motor leads: one is cylinder shaped (100V, 47uF) and the other is rectangular and smaller and i cannot decipher any writing on it. am i right to assume the cylinder shaped one is the one to replace? i suppose i can’t kill a dead horse and i will get one at radio shack and try it out. if that don’t work i’m just gonna buy another circuit board. thanks for the tips people i will let you know what happens.
beowulff what do you mean if it’s putting out ac? i would see that in the voltage reading with a multimeter, right? it would bounce between negative and positive values?
If you set the Meter on DC, it will read zero, or close to it, when measuring AC.
If the controller is outputting DC, the meter should read zero, or close to it, when set on AC.
I’m pretty sure that this controller should be putting out DC - so if you are measuring AC voltage, there’s something wrong.
An oscilloscope would help, but I suppose that’s too much to ask for.