I'm a beekeeper. My honey extractor is powered by a General Electric DC motor 120 volt 6.2 amp. I think it's a universal type motor, so it can be ran with dc or ac. The model is BD6219. I've ran it with straight mains ac(of course no speed control) and with the controller board that contains a triac. I would like to use an arduino to control its speed by pwm. I'd like to start it slow and gradually speed it up. If it shakes too much it should cut the speed to maybe 25% and run for a few minutes before speeding up again. I think I can detect shake with a piezo device but the motor speed control is where I get lost. I've looked at solid state relays and triacs. Anyone have an idea how I should proceed?
Why no replies?
From what I can find on the net that's a DC motor, not a universal motor.
Maybe my info was wrong but I've run it with both types. It worked fine. What would be the best way to control the speed on this motor?
If you try AC then you can try this. this is the best way. This is for AC. Use BTA12 TRIAC H11A1 for reading the zero cross over.
This guy doing same like mine.
As I said it appears to be a DC treadmill motor. Running it as a universal motor would be uncharted territory.
Does it have 4 wires, two thick and two thin?
Yes. It has two power wires and two that are used to measure speed.
You can run it using single phase VFD if you want to run it on AC.
Otherwise DC motor driver is best solution to give variable speed to your motor.
Using AC VFD makes work easy as it have lots of functions and can be connected to Arduino easily to automatically increase speed of your motor.
I'm going to test the output of the control board to make sure this motor is DC. If it is ac would it be possible to run it on a solid state relay?
Yes, but a solid state relay won't provide speed control.
I thought a solid state relay could be controlled by pwm? What would you recommend besides a vfd?
Does this motor have brushes and a commutator?
If so it's a universal motor - ie the field is in series with the armature.
If so you can control it with a triac and a variable angle trigger.
You can't control it with variable frequency.
SureshKumar2610 has provided links.
It's possible it's a squirrel cage motor , in which case there will be a large external capacitor and no brushes, and the armature will not have windings..
In which case a variable frequency control is the best way
It's also possible it's a hybrid - wound armature, brushes and slip-rings . These need computer control. But since you say it only has 2 power wires, this is unlikely.
You say it's controller board already contains a triac... does this mean it already has some sort of variable speed controller? If so it might be easier to hack that.
regards
Allan
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You say it's controller board already contains a triac... does this mean it already has some sort of variable speed controller? If so it might be easier to hack that.
I'm really glad you brought this up. My next question was going to be how to use the existing board with an arduino. It uses a 10k pot for input for speed. I considered using a servo to turn it but, that doesn't seem right. Is there an arduino controllable adjustable resistance device? This motor has no external capacitor. It's a treadmill motor.
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I'm really glad you brought this up. My next question was going to be how to use the existing board with an arduino. It uses a 10k pot for input for speed. I considered using a servo to turn it but, that doesn't seem right. Is there an arduino controllable adjustable resistance device? This motor has no external capacitor. It's a treadmill motor.
I know it seems clumsy, but the servo might be the simplest approach - that pot is probably floating at mains potential.
Alternatively perhaps 2 ldr's with variable illumination by 2 LED's... hard to calibrate and not very stable..
Allan.
JonBurchett:
I'm really glad you brought this up. My next question was going to be how to use the existing board with an arduino. It uses a 10k pot for input for speed. I considered using a servo to turn it but, that doesn't seem right. Is there an arduino controllable adjustable resistance device? This motor has no external capacitor. It's a treadmill motor.
You can use a digital potentiometer but most digital pots are limited - the voltage being controlled can't go outside the bounds of the power supply. So a 5V Arduino can't control a 10V circuit this way. Additionally, you are making a direct connection between the Arduino ground and the ground of the controller board, which may not actually be at Earth potential.
I don't know if I said it has a triac being controlled thru the board by a 10k pot.
Then the pot is probably at mains potential and you can't use a digital pot.
It might be worth changing the speed controller entirely so you can get one that is controllable with an Arduino.
Or as in my crude earlier suggestion - use a arduino controlled servo on the pot.
Allan
I'm kind of down to just using a servo. One thing though. This is a 2hp motor and just a small amount of turn on the pot gives it more speed than I need. Can I change that pot to one of a different value to give me a larger amount of turn on the pot for the same speed increase? I can turn it less than a quarter turn and its spinning faster than I'd like. Actually with a half turn it will take off across the room. Kind of dangerous. Think of a 55 gallon barrel bouncing thru your kitchen.