BVH
Flashaholic
I've assembled a DeWalt 36 Volt 10S4P pack (36 Volt, 9.2 Amp using A123 cells) that leaves each 36 Volt pack unmodified so I can still charge each one with the 1 original DeWalt balancing charger I have - so hopefully my chances of not only balanced cells is maintained but also, the packs stay somewhat balanced as units having come off the same charger. After 24 hours rest, I end up with a multi-pack Voltage of about 35.4.
The light I want to run is my 28.8 Volt Locator, a 350 Watt (as recently measured) Helicopter targeting light. I am concerned about supplying an initial 35.4 Volts to the 28 Volt rated light. I've done it using a Cheap Battery Pack brand 24 cell, 4.5 Amp pack which starts at about 34.5 Volts and immediately drops to 32.5 Volts or so and the light has no issues. However, using A123 cells and a double Amp capacity pack, I am concerned that Voltage sag will be extremely low and that I might blow some electronic circuitry. When I was using 3 custom made, A123 packs using 9 cells instead of 10 and having a total capacity of 6.9 Amps, I had an initial sag of only 1 Volt. There is one fuse integrated with the ballast circuitry but I don't really know if it's in the "input" stage.
I know a lot of you here on CPF are very knowledgeable when it comes to Voltage regulation and have designed and built your own small units. I am familiar with the terms PWM and FET but certainly don't have the expertise to build or enough knowledge to buy something that would regulate a 36 Volt DC, up to 20 Amp source down to no more than 30 to 32 Volts and that can be used in an HID electronics input power setting. Having a low voltage cutout would be a bonus, somewhere around 24 Volts.
If something like this exists, does it consume significant power such as a resistor would do when placed in a circuit as opposed to PMW which more or less varies the time Voltage is "on" during a cycle but probably consumes very little operating power? I would not like to consume any more power than is necessary so that my run time is kept as long as possible. Size of a unit and any heat are not really too much of a concern as the device could be put in my open battery box.
What say you, experts?
The light I want to run is my 28.8 Volt Locator, a 350 Watt (as recently measured) Helicopter targeting light. I am concerned about supplying an initial 35.4 Volts to the 28 Volt rated light. I've done it using a Cheap Battery Pack brand 24 cell, 4.5 Amp pack which starts at about 34.5 Volts and immediately drops to 32.5 Volts or so and the light has no issues. However, using A123 cells and a double Amp capacity pack, I am concerned that Voltage sag will be extremely low and that I might blow some electronic circuitry. When I was using 3 custom made, A123 packs using 9 cells instead of 10 and having a total capacity of 6.9 Amps, I had an initial sag of only 1 Volt. There is one fuse integrated with the ballast circuitry but I don't really know if it's in the "input" stage.
I know a lot of you here on CPF are very knowledgeable when it comes to Voltage regulation and have designed and built your own small units. I am familiar with the terms PWM and FET but certainly don't have the expertise to build or enough knowledge to buy something that would regulate a 36 Volt DC, up to 20 Amp source down to no more than 30 to 32 Volts and that can be used in an HID electronics input power setting. Having a low voltage cutout would be a bonus, somewhere around 24 Volts.
If something like this exists, does it consume significant power such as a resistor would do when placed in a circuit as opposed to PMW which more or less varies the time Voltage is "on" during a cycle but probably consumes very little operating power? I would not like to consume any more power than is necessary so that my run time is kept as long as possible. Size of a unit and any heat are not really too much of a concern as the device could be put in my open battery box.
What say you, experts?
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