12-01-2019, 04:02 PM
I had a brain fart moment regarding the current running through resistor pack, and comparing amperage above.
The wattmeter was placed before the PWM MSC, but after the resistor pack.
The voltage was reduced by the resistor pack but feed voltage into the PWM MSC was held steady by the mean well above battery voltage. I can place wattmeter after PWM MSC but the output voltage might be inaccurate.
The resistor pack is wasteful of amperage but not as wasteful as I posted above.
Should have gone by wattage, as that takes into effect different voltages.
I can;t really take amp readings easily on stock wiring before the stock resistor pack nor voltage, so I could then see wattage in vs wattage out at reduced speeds and see just how much the resistor pack is burning up as heat. I guess some math can arrive at similar conclusions, but small errors in voltage could throw the wattage numbers off pretty good.
Either way it is pretty awesome having the ability to turn on the HVAC blower with engine off, to any speed and noise amperage level I desire. Its not the most electrically efficient way to force fresh air inside, but it works.
I'm gonna run some 10awg to feed the PWM MSC, and also make a quick disconnect for the vaccuum operated lever which shifts vents from dashboard to defrost/footwell, but perhaps not for a while yet. I can just hook it back stock for now and use a extension cord when I want to use the PWM MSC.
The wattmeter was placed before the PWM MSC, but after the resistor pack.
The voltage was reduced by the resistor pack but feed voltage into the PWM MSC was held steady by the mean well above battery voltage. I can place wattmeter after PWM MSC but the output voltage might be inaccurate.
The resistor pack is wasteful of amperage but not as wasteful as I posted above.
Should have gone by wattage, as that takes into effect different voltages.
I can;t really take amp readings easily on stock wiring before the stock resistor pack nor voltage, so I could then see wattage in vs wattage out at reduced speeds and see just how much the resistor pack is burning up as heat. I guess some math can arrive at similar conclusions, but small errors in voltage could throw the wattage numbers off pretty good.
Either way it is pretty awesome having the ability to turn on the HVAC blower with engine off, to any speed and noise amperage level I desire. Its not the most electrically efficient way to force fresh air inside, but it works.
I'm gonna run some 10awg to feed the PWM MSC, and also make a quick disconnect for the vaccuum operated lever which shifts vents from dashboard to defrost/footwell, but perhaps not for a while yet. I can just hook it back stock for now and use a extension cord when I want to use the PWM MSC.
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