Nu Relic power window issue

[colorado80439]

Originally Posted by blitzer454

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.

Thanks for chiming in!
I haven't seen that variable resistor in my search, it's reasonably priced so I bought it for testing.
I'll reply with the results

By the way, any issues with your window speeds?

Thanks again

[dhutton]

You are a glass alignment god if you only need 3 amps to raise and fully seal repop glass on repop weatherstripping....

Don

[blitzer454]

Originally Posted by colorado80439

By the way, any issues with your window speeds?

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

You are a glass alignment god if you only need 3 amps to raise and fully seal repop glass on repop weatherstripping....

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.

[dhutton]

Originally Posted by blitzer454

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.

You should have taken the glass alignment god title and ran with it…

Don

[colorado80439]

I purchased the variable resistor and tested at several settings and 1 ohm gave me 1 volt drop which seems to be a perfect speed, that was at a battery voltage of 12.5 so it may be a little faster with the alternator turning. I have a 1 ohm 300watt resistor picked out and I will need a diode.
Not sure what Schottky Diodes to purchase looks like I need to know forward current, reverse repetitive voltage, forward voltage, forward surge current, and reverse current. I'm assuming I should look for the known values of 12-15 volts, and 20 amps. Any input would be awesome.
Thanks
https://www.mouser.com/ProductDetail/284-HS3001RJ

[dhutton]

Blitzer is the expert but I would shoot for minimum 30 reverse volts and minimum 30 forward amps. Forward voltage should be as low as you can find. The rest of the specs won’t make any difference imho.

Don

[blitzer454]

Don's specs are good, I would only add that I would find one that is physically big enough to work with and high surge current rating. I would go with the SBX3040-3G as it meets all the requirements and is also cheap.

For the resistor the FVE030020E1R20KE would get the job done for less money.

[colorado80439]

Awesome! It's so cool and fortunate to get this kind of assistance, I will follow up with my findings
Thanks again

[Ketzer]

Fascinating thread...I dont understand a single word of it...but am amazed by what you guys are talking about and the fact that you found a solution!


Jeff-

[colorado80439]

I ended up using this resistor
https://www.mouser.com/ProductDetail/284-HS3001RJ
And this diode
https://www.digikey.com/en/products/...4S1-D3/5068422

They both qualified for the parameters we were looking for and the packaging was convenient for mounting.

The front windows now work at the same speed up and down.

Thanks again for all the awesome assistance