Originally Posted by blitzer454 (Post 712575)

Hmm, I use the New-Relics power windows in my car and they only draw around 2A when moving up or down. When the window hits one of the stops the current will shoot up. I have my over-current limit (stall) set to around 3A on my automatic up/down circuit.

I don't recall that they gave the current limit specs when I purchased my motors, I wonder if they did change to a different motor.

I think you are right that the low load is window going down, high load is going up and stall is when the window reaches one of the stops.

You probably should design around the 5A low load spec when choosing the resistor, but know that current can get as high as 20A if you leave your finger on the switch too long after the window hits the stop.

I would shoot for a variable resistor under 10 ohms rated for 300W or more. Like the AVE030020E8R00KE. Try it without the diode first you might get lucky.

Originally Posted by colorado80439 (Post 712603)

By the way, any issues with your window speeds?

Originally Posted by blitzer454 (Post 712619)

My windows are quick but I don't feel they are excessively fast.



Okay I went back and double checked my measurements and I did screw them up. I have my over current A/D count value set to 0x200 (hex) which translates to 2.5V (10 bit A/D counter with 5V reference). I was mistakenly taking that voltage value as the current forgetting that I have a voltage divider on the A/D channel such that 5V scales to 30A. So 2.5V is actually 15A. On a side note I have the rear window over-current set to 0x115 which translates to 8.11A. Sorry for the confusion.

So I guess the Nu-Relics spec values are actually pretty close to what I'm seeing in the real world.

I would like to say that my windows are perfect, but they're not. They like to leak around the seal at the top of the window when I hit them with the water hose, but they're not to bad in the rain.