Big Ed 3750 + Big D 3850 Xenon Lamp?

[adamlau]

The recent ROP threads have me considering driving the 24W and/or 11W Big D 3850 Xenon lamp with the Big Ed 3750 and its 4C-NiCad pack, which runs 4.8V, 2.4A. Would underdriving the Big D 24W and/or 11W result in greater, or less output than the Big Ed driving its primary OEM Xenon lamp (4.8V, 1.6A)?

 

[RoyJ]

I'm a little confused here, are you trying to compare the 3 bulbs all driven at spec?

If so then simply go by their ratings - 24w > 11w > 8.2w

Also, what cells are you using to drive them? Keep in mind that with 6 consumer ni-mh AAs, they're only averaging 1.1V @ 4+amps. Combined with the Mag resistences, you're probably only seeing 6V v-bulb anyways.

The only cells that'll hold a true 1.2V+ under 4 amps are high drain AAs, As, sub-Cs, or C/Ds.

 

[adamlau]

The high drain 4C-NiCad pack of the Big Ed drives the primary OEM Xenon lamp at 4.8V, 1.6A. Was wondering how that would compare to driving the 24W and 11W Big D 3850 Xenon lamps.

 

[RoyJ]

Alright, gotcha ya.

In this case the 11W 3854 would be SIGNIFICANTLY dimmer at 4.8V compared to the OEM Big Ed. You'll end up with a ridiculous bulb life like 500 hours, but very dim.

From this bulb test: http://www.candlepowerforums.com/vb/showthread.php?t=184874

You'll see that the ROP-lo driven at 4.8V gives about 1/4 the light intensity it does at the 7.2V ROP level, and less than 1/2 the light intensity it does at the OEM 6V level.

Doing linear interpolation on the above graphs, the ROP-hi probably will exceed the stock Big Ed lamp in terms of sheer brightness, but the light quality would be very poor (yellow).