You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter a111r
- Start date

0.3A means anything from 250ma to 349ma. The range of the pot is probably too low to make a 100ma swing in the current.

It matters not, If we assume 300ma is the max at 110V we would want for say a swing from about 10% through to 100% or 35ma to 350ma (It's debatable if the motor will even start at 35ma but you never know). 110 / 0.3 is 366 ohms (this is AC so not strictly the same as DC resistance but we're ball park figures here). To get 35ma we'd need 110 / .035 = a total of 3142 ohms. Take off the 366 and we're left with 2776 ohms - nearest E12 is 2.7K.

I'd doubt you'll find a 2.7K wirewound - more like 2.5K but even that seems a bit too high.

Before rushing out and spending on a 2K pot, do you have any wirewound resistors to hand, I'd try sticking a couple of 1K 5W wirewound resistors wired in series in place of the pot and see if the motor will start. It should do if my maths is right but whether it will with a bit of wire to push through is a different matter.

Slaying a chicken and seeing how the entrails lie, 500 ohm on a loaded motor feels better than 2K

Have you got a 500 or 470 ohm power resistor ?

Without circuit diagrams and details, we're down to component substitution to find something that will just allow the motor to spin.

On the older post linked earlier, it did look as if there was already a 71 ohm 11W power resistor in series with the pot so we could well be looking for something lower than 500 ohm, possibly 100 ohm would be a good so anything in your collection in that range would be a good start.

A minty original AW-2 has just appeared on Ebay:

Find many great new & used options and get the best deals for Vintage Norman butter.NBC Autoweld 2 mig welder.240 volt at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk