Electric motor help

   / Electric motor help #1  

slydog

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Southaven, Ms now, Greers Ferry Ark later
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Im building a Christmas float, and in order to animate/spin something I needed a small motor. Ive got one out of an old bread machine. I know the motor worked before I removed it. The tag on the motor says:

GoldStar
Model No: HMR031L3
120v/60hz 1.0A
Thermally protected
Time rating: 40MIN

There are three wires coming out of the motor; White, Grey, and Brown. These were initially wired through the circuit board with all the switches, sensors, etc that controls the bread making cycle, but I don't need all that garbage. I just want to spin the motor. I BELIEVE the white wire might be the hot and either of the other may be a ground??? I'm thinking this is either a two speed motor, or perhaps it operates in reverse?? depending on whether you have power to the grey or the brown wire???? I connected the white wire to one side of a stripped power cord, plugged in the cord and would touch the other power cord wire to either the brow or the grey wire. It would spark just a little, but the motor wouldn't spin. I was afraid to just twist the other two wires together, not knowing if I was hot to hot and zapping myself, throwing a breaker or burning up the motor. Can any of you electric motor guys out there help me with this? Do I need some kind of transformer or something I need to wire through, or can I just connect a lamp cord type wire to two of these wires coming out of the motor and make it work? Which two???

Thanks for any help yall might offer.

Ken
 
   / Electric motor help
  • Thread Starter
#2  
Okay..I got it working...but can someone explain to me what this is and why it wouldn't work without it. There was a small black plastic box which the brown and grey leads from the motor initially plugged into. I wired the white from the motor to one side of my extension cord, plugged the grey and brown wires back into the black box; then the grey wire coming out of the black box I wired to the other side (hot side) of my extension cord. Plugged her in and away she went. The black box reads:

Yuhchang (obviously the manufaturer)
10MFD/U
250WVAC (then what looks like a backwards RU. Sort of like this but pushed together 9U)
-25 (degree) C - 80 (degree) C

What is this black box? Why wouldnt the motor work without it being wired in, just connecting either the brown or the grey wire to the hot from the extension cord? Is the moon really made of cheese? Is there really a Santa Claus? Why do I have so many questions? /forums/images/graemlins/confused.gif /forums/images/graemlins/grin.gif

I wish I had taken an electronics course in my younger days!!!

Ken
 
   / Electric motor help #3  
</font><font color="blue" class="small">( Okay..I got it working... The black box reads:

Yuhchang (obviously the manufaturer)
10MFD/U
250WVAC (then what looks like a backwards RU. Sort of like this but pushed together 9U)
-25 (degree) C - 80 (degree) C

What is this black box?
Ken )</font>

The black box is a capacitor (aka condenser). Some, but not all, AC motors need capacitors to run. 10 microfarad with a rating of 250 working volts alternating current. The RU label is an European (?) organization equivalent to Underwriters Laboratory (UL).

Have you thought about using a small DC motor, say from a car window lift? It might be safer than wiring a up a 117 vac motor. But, a bird in the hand. . .
 
   / Electric motor help #4  
<font color="blue"> The RU label is an European (?) organization equivalent to Underwriters Laboratory (UL).
</font>

The backwards UR is actually a symbol for a UL recognized part to go into a UL listed item.
 
   / Electric motor help
  • Thread Starter
#5  
</font><font color="blue" class="small">( The black box is a capacitor (aka condenser). Some, but not all, AC motors need capacitors to run.[/qoute]

Kind of like a hard start capacitor on a condensing unit I guess. Since the bread machine would have been starting under a load with all the dough in it?

</font><font color="blue" class="small">( Have you thought about using a small DC motor, say from a car window lift? It might be safer than wiring a up a 117 vac motor. But, a bird in the hand. . . )</font>

Well...as you said, a bird in the hand. I didn't want to spend any more money on this thing than I"ve already spent. Plus, I am already using several spot lights on the float, and a stereo cassette player which I am powering with a small honda generator. The motor and the capacitor are already mounted on a small flat metal frame, so all it required was plugging the two colored wires from the motor back into the capacitor. The only wiring I am actually doing is is the power cord to the white wire coming off the motor, and the power cord to the grey wire into the capacitor. I will use screw caps on these and tape over all connections. I do know enough about capacitors to know about the hazards of discharging a charged one; now that I know it's a capacitor. This unit will all be mounted inside a big plywood light box so no one but me will be in any possible contact with it. I have finished this part and looks like a huge "lite brite" box in the shape of a heart..turned out really great btw! /forums/images/graemlins/smile.gif

I will have to fabricate a couple of pulleys to reduce the speed a little which will also be mounted inside the box. This will be turning a "key" head I am making out of plywood that will stick out of the back of the box and "unwind" as it pushes the float down the road. Just a little something extra to see on the back of the float after it passes. It wasn't a necessity for the overall design, just a little something extra I wanted to do if I had time.

I have one more question though. How do I figure the total load on the generator as I don't want to overload it. I plan on running 3 - 100 watt floods, 2 - 75 watt floods, this small motor, a pioneer stereo reciever with a cassette player, and possibly two or three strands of those small christmas lights. I am not sure what the generator is rated at as we are borrowing it from one of the participants work and it wont be available till just before the parade. All I know right now is that it is a small, quiet Honda generator. Wheww...sorry so long, but I really appreciate all you guys help!

Ken
 
   / Electric motor help #6  
The charged capacitor issue is going to be virtually null in this situation.. 10mic's is not much capacity. In some cases where you are dealing with really large start and run caps, there is a high value bleeder resistor.. like 10k or 100k across the cap leads.. this bleeds the residual charge off.. again.. pretty much negligible in your scenereo.

As for wattage.. voltage times current will give you power (watts).. Therefore a 10 amp load would draw 1200 watts on a 120v line. Add your total load. The radio will porbably list toatal load at full operating volume to account for the amplifier draw. The xmas lights will also have a total wattage tag. If you had any large motor loads, sometimes you have to figure for 2x ( and even3x ) load for starting, and then 1x load rating for running... however your breadmachine motor is drawing what? 1 amp? again.. negligible... I imagine a 3250w genny would do ya.. heck.. a small 1000 or 1200 will probably do ya unles your hi-fi is huge..

Soundguy
 
   / Electric motor help
  • Thread Starter
#7  
Thanks SG!
It's not a big honking stereo, just an a 1987 model rack system that I will only be using the reciever portion with the built in cassette deck and a couple of old pioneer speakers which are probably less than 50 watts per channel. I will not have any start up load other than that small capacitor on the small motor I have already mentioned. The rest will just be in lights.

Ken
 
   / Electric motor help #8  
Even if you did have some high draw inductive starting loads.. like compressors or other electric motors.. as long as the genny has the capacity to get it going, start that/those loads first.. then bring on the resistive loads.. perhaps on a seperate power strip. ( You won't have any problems.. )

Soundguy
 
   / Electric motor help
  • Thread Starter
#9  
Well, after all you guys advice I put the motor in the box and to slow down the rotation I had built a plywood pulley about a foot in diameter, and got it installed and it was all working well up to that point. Since I had no way of tensioning a drive belt, I was trying to use some surgical tubing to drive the darn thing. The weight of the key I had constructed from plywood was just too much for the tubing, so basically after piddling with it for about 4 hours, I could'nt get it to spin the key.

The whole time I have been building this, I had been walking over and on top of of this box that was in my way in the storage shed. When I needed a solution Friday night for it, as our parades were saturday it finally dawned on me. The box I had been tripping over was a universal rotisserie I had bought on clearance that wouldn't fit my grill and I'd just thrown the whole thing in the shed. It took me about 30 minutes to cut it down and install it, and my key spun like a champ at the perfect speed.

Here is a link to the pictures of the float if anyone is interested. You can see the "lite brite" effect in the ones that were taken at night. Unfortunately, I didn't get a picture of my big wind up key on the back of the box. We won first place trophy's In all three of the parades we participated in. Here's a link to the pics I did get.

Light box/float

Ken
 
 
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