NEED SOME HELP ON HID CONFIGURATION

[gammaray1965]

I have a 32watt hid lamp with the following specifications: Operational Voltage= AC 85V + 12V Wattage= 30W + 2W Current input= 2.7amps. Now the ballast: Vin= 10V~16V Vnorm= 12.8VDC Inorm= 3.5A Pout= 35watts +-5% Operating Power=AC85 +- 15V. Power Supply= 6 cell Li-ion 5200mah with circuit control. The power output of this battery pack is 8.5V~12.5V DC.

Question#1- How long will the run time be before I would have to re-charge the battery pack?

Question#2- Could I use lets say a 14.8 Li-ion pack and would this voltage be alright with the ballast?

 

[LightForce]

Hi gammaray1965,

In my opinion it's better to use just a 35 W lamp.

Your batterypack has a nominal voltage 11,1 V and 5200 mAh of nominal capacity, which gives you ~57 Wh of energy storage. You seems to have an automotive-style ballast with ~83% efficiency, which gives you 42 W input power. Dividing Wh with a ballast input power you'll get an estimated ~80 mins of runtime.

I've tried 14,8 V configuration with Hella and Philips automotive ballasts, and not all the units wanted to cooperate with it, as a peak voltage of freshly charged Li-Ions reached 16,8 V and overvoltage protection in a few ballasts momentally switched off the lamp. Another units gave such a voltage sag, that it could work properly later. So you can't have a certainty that your ballast can handle it. If you very slightly discharge your pack, voltage quickly lows below 16 V. Or use an 0,5 ohm resistor for lowering highest voltage of the cells below 16,8 V.

8 cells configuration gives you 33% more capacity and slightly better ballast efficiency.

Cheers,
Damian

 

[gammaray1965]

Thanks LightForce, Much Appreciated! So in other words by adding a 1/2 ohm resistor inline with the positive input side to the ballast would be sufficient for the Li-ion 14.8V batt pack. Also, what should the resistors wattage be?

 

[LightForce]

Since you have 10 - 16 A current surge and P = I^2R, it should be a huge resistor. I used 5 - 10 W values becouse in fact ~4 sec. of such a high current don't even warm the resistor.

Later you'll have ~4 Watts of losses on it. 0,2 ohm resistor value gives you ~2 Watts of losses. System efficiency will suffer.

Measure starting current of your ballast. Maximum that your Li-Ions can handle is 10 A.

 

[gammaray1965]

Thanks Again LightForce! By the way how much for the M4A1 (MagT5), that baby must put out some lumens!

 

[LightForce]

Yes, this is a real wall of ligt...

As it exists as a complete light only on the picture, I really can't estimate any costs. But it won't be cheap, it's sure.:naughty: When I assemble it and carefully test it step by step, I'll introduce this baby here on CPF.

Cheers,
Damian

 

[gammaray1965]

Are you making them or just assembling the parts?

 

[LightForce]

This is my own project. If I mismatch any word, it's only due to my poor english level.

 

[gammaray1965]

what type of ballast are you using?

 

[LightForce]

It's non-automotive, 27 - 45 W regulated ballast specially designed for D2 lamps and 9 - 19V input voltage range. Small enough to fit extended Maglite head.

 

[gammaray1965]

Did you get the e-mail I had sent you?

 

[LightForce]

gammaray1965, PM sent.

 

[gammaray1965]

I got it, message sent.

 

[XeRay]

It's non-automotive, 27 - 45 W regulated ballast specially designed for D2 lamps and 9 - 19V input voltage range. Small enough to fit extended Maglite head.

Is it a 50 mm cylinder?

 

[LightForce]

Is it a 50 mm cylinder?

Yes.

 

[XeRay]

50-60 mm is perfect for cylinder ballast.