DC 1.8V 3V 5V 6V 12V 2A motor speed controller 30W PWM 1803b K7 L6

Swoffer · Senior Member

Voltage reducing .

Warren-Pat_01 · Guru

G'day Al,Will the motor still drive with sufficient torque to turn the rod when it is running with 1.5v?I guess there's one way to find out.

The resistor you were sold is a 27ohm, 10w - obviously too much resistance.
Do you have a multimeter where you can read the resistance of the motor (across the leads)? Then just get an equivalent value resistor & add it in series with your motor.

OR get a LOW resistance wire wound potentiometer (variable resistor) & add it in the circuit - that way you can vary the speed to what is needed.

Swoffer · Senior Member

Warren-Pat_01 wrote:
G'day Al,Will the motor still drive with sufficient torque to turn the rod when it is running with 1.5v?I guess there's one way to find out.

The resistor you were sold is a 27ohm, 10w - obviously too much resistance.
Do you have a multimeter where you can read the resistance of the motor (across the leads)? Then just get an equivalent value resistor & add it in series with your motor.

OR get a LOW resistance wire wound potentiometer (variable resistor) & add it in the circuit - that way you can vary the speed to what is needed.

Like something like this from Ebay for instance ?

Have one to sell? Sell now

DC 1.8V 3V 5V 6V 12V 2A motor speed controller 30W PWM 1803b K7 L6

dorian · Guru

Would it be possible to redesign the "rod turner" using the 240VAC turntable motor from a discarded microwave oven?

Swoffer · Senior Member

dorian wrote:
Would it be possible to redesign the "rod turner" using the 240VAC turntable motor from a discarded microwave oven?

Gday Dorian .

Yeh possibly down the track but I'd like to get it running in this format for now because my old dad (88yo) built it for me this week in his workshop at home , so if its not to expensive I'll keep it as it is for now if I can .

So I've just ordered one of the little PWM controllers off Ebay .

Get this , $1.72 with free postage to Aus , dont know how they do it really , but i'll try it and see .

Cheers Al

T1 Terry · Guru

woffer wrote:
Warren-Pat_01 wrote:
G'day Al,Will the motor still drive with sufficient torque to turn the rod when it is running with 1.5v?I guess there's one way to find out.

The resistor you were sold is a 27ohm, 10w - obviously too much resistance.
Do you have a multimeter where you can read the resistance of the motor (across the leads)? Then just get an equivalent value resistor & add it in series with your motor.

OR get a LOW resistance wire wound potentiometer (variable resistor) & add it in the circuit - that way you can vary the speed to what is needed.
Like something like this from Ebay for instance ?

Have one to sell? Sell now
DC 1.8V 3V 5V 6V 12V 2A motor speed controller 30W PWM 1803b K7 L6

These sort of things are great as long as it can pass the start current you need at 1.5v, divide the motor watts by 1.5 to get an idea of how many amps you might need, not a terribly accurate equation but it will give you a guide. Next is to make sure it can actually drop the voltage to 1.5v, the adjustments are not always linear. I used the opposite idea to boost an 18v power tool battery to power a 40v LED flood light using the assumption that if it could boost 12v to 36v then it would easily boost 18v to over 40v ..... you know what they say about assuming :lol: Still the same max voltage of 36v, but fortunately the LED flood light still works fine at that voltage so in this case no harm done. The design aim with the flood light was to make it small and cheap so if it got stolen it wouldn't break the bank.

T1 Terry

dorian · Guru

Here are the full size images:

As for the LED flood light, ISTM that the booster converter circuit could probably be modified to output 40V instead of 36V by recalculating the value of a feedback resistor. I could help with that, if necessary.

-- Edited by dorian on Thursday 8th of February 2018 03:12:04 PM

T1 Terry · Guru

Thankyou for the offer Dorian, if it turns out to be a worth while project then I may just take you up on that. The boards themselves are cheap as chips on evilbay so I thought I'd give one a try.

T1 Terry

Warren-Pat_01 · Guru

Looks good!

Aus-Kiwi · Guru

Light in series ??

Swoffer · Senior Member

Aus-Kiwi wrote:
Light in series ??

Sorry ?

Swoffer · Senior Member

Warren-Pat_01 wrote:
Looks good!

Thanks

hako · Guru

You could try using rechargeable batteries which are 1.2v each so 2 = 2.4v.

Swoffer · Senior Member

hako wrote:
You could try using rechargeable batteries which are 1.2v each so 2 = 2.4v.

Yeh thats an option Dennis . I'll try this little hoodjigger from China first and see .

sandman55 · Guru

We don't know what current the motor draws, if you try the variable resistor idea and it (the vairable resistor) gets warm then you need to increase the wattage. As someone said I wonder if the motor will have enough torque at 1.5 volts. What are you using as a power supply. If you want to try it out you could get some "D" cell batteries and depending on the size of the motor to keep the batteries at 1.5 volts but increase the capacity connect the positives of the batteries together and the negatives together that way you will get more current but maintain 1.5 volts. You will then see how it runs and if it has enough torque and see if the motor gets hot. Another way is get another resistor the same from Jaycar and put the two in parallel (side by side) that way you will halve the resistance three in parallel will give you one third of the resistance.

-- Edited by sandman55 on Saturday 10th of February 2018 09:18:08 PM

-- Edited by sandman55 on Saturday 10th of February 2018 09:23:37 PM