PWM on 12volt winch?

[Maglatron]

Quote

That's reasonable. But applying the same factor of 5, that means the OP would be looking to source one rated at 5 x 114A = 570A !

hmmm,
Mr Alec_t could you skip over to the IR2110 thread, I have a question!

 

[Maglatron]

ok been searching all day can anybody tell me where to get a variable speed winch or how to determine the type of motor that I have, to then move on to how to tackle the task of making a PWM controller please, thanks

 

[kellys_eye]

Spec says it's a permanent magnet motor. Full pull current is 200A at 12V.

 

[Maglatron]

good man! I missed that, so what does that suggest, motor type wise? wait that was stupid it's a permanent magnet motor can you you PWM on that?

 

[kellys_eye]

That's reasonable. But applying the same factor of 5, that means the OP would be looking to source one rated at 5 x 114A = 570A !

The x5 would only apply to 'dodgy' source units. As per Bluejets saying 'quality' product, such a device would work when rated at 250A or even 200A with suitable fusing/breaker for protection.

 

[Maglatron]

can I buy or is it better to make a controller?

 

[kellys_eye]

Personally I'd use a 100A device (with suitable thermal/overcurrent trip, resettable) and be careful how I used it. I'd also use a bypass switch to run it at full current when that was necessary - probably not very often.

can I buy or is it better to make a controller?

Even a low current controller can be modified to work at MUCH higher currents by changing the switching device (probably a MOSFET) for one - probably a few wired in parallel - device rated for much higher current.

You can get N-channel MOSFETs rated at 30V and 500A (IRDS(on) value of 0.0007ohms!) for £1.20 at Farnell.

Use any good component supplier and their parametric search engines.

 

[Maglatron]

I have bought the winch a while ago and it's being stored at my friends till I come to use it. I'm just getting ready for when I do use it.

Personally I'd use a 100A device (with suitable thermal/overcurrent trip, resettable) and be careful how I used it. I'd also use a bypass switch to run it at full current when that was necessary - probably not very often.


Even a low current controller can be modified to work at MUCH higher currents by changing the switching device (probably a MOSFET) for one - probably a few wired in parallel - device rated for much higher current.

You can get N-channel MOSFETs rated at 30V and 500A (IRDS(on) value of 0.0007ohms!) for £1.20 at Farnell.

Use any good component supplier and their parametric search engines.

this seems like a good way to go, any controllers in mind? I would like push buttons to gradually increase current with each press and one to do down or a knob pot

 

[Maglatron]

so that is really taking my interest can you draw up a rudementary picture with labels on a paint diagram please like a rough guide of the steps involved, thanks

 

[Maglatron]

asin how you would achieve it

 

[Martaine2005]

Winches are geared motors. Slow speed and high torque.
What is the purpose of PWM?. The winch is already designed for max torque at a sensible RPM.
Are you taking the gearbox away?. That’s the only way to achieve what I think you want. Then, you’ll lose the torque and get high RPM.
I personally don’t think you’ve thought this through!

 

[Maglatron]

No I want to gradually increase the speed of the winch, not just on or off, to take out the jerk, for that project a jerk would cause damage! when the winch turns on it immediatly goes from 0 m/s to 10.5 m/s I need it to be gradual! I have thought about it a lot to be fair

 

[Martaine2005]

Lower the voltage. It will slow down.

 

[Maglatron]

hmm

 

[Maglatron]

so just use a massive pot?? know where to get one looking on mouser no joy

 

[Maglatron]

could this work https://www.amazon.co.uk/Potentiome...&sprefix=300+watt+potentiometer,aps,77&sr=8-2

 

[Alec_t]

could this work

Its SCR is rated only 3A, not 200 !

 

[Maglatron]

Its SCR is rated only 3A, not 200 !

oh I put the max amperage at 20 and multiplied by 12 for power equals 240watt so I thought the 300watt pot would work, I don't know what SCR is can you recommend a different one

 

[Maglatron]

oooohhhhh I realised what I just did, derrrr 20 amp at no load!

 

[Maglatron]

any suggestions, reconsidering the modified controller with the parallel mosfets need abit of help with it though, thanks