Another LC100 Question

I use 2 lc 100's for underwater photography and video.
I would like to take the LC100 light heads and put them
in smaller housings, thus making a separate battery pack.
Now for my question.
Can I drive both light heads with 8 C or D cells?
I plan on using nimh rechargables, from what I understand
the higher the MAH the better, what would be your recommendations?
8 D cells are still lighter than 16 C cells.
Any guesses on how long the light will last?
Any ideas on where to get waterproof plugs & cables?
Any recommandations would be helpful.
I am very handy and have no problems with fabrication.
Thanks in advance

Gitarzan56,

I wanted to do the same thing to my LC100 but do not have the expertise with fabrication, so maybe if your design is succussfull we could talk more about it later. (Maybe pay you for your services? /ubbthreads/images/graemlins/grin.gif)


I've done some thinking on this subjuct as well. Underwater Kinetic's site lists the light as a 10V/1.25A light. I wonder what the tolerance is of the ballast because 8 Alkaline batteries, with a nominal output of 1.5V each, total 12V. 8 NiMH batteries, with a nominal ouput of 1.2V have an ouput of 9.6V. 10NiMH batteries would give you the 12V a fresh Alkaline battery pack would give. But since Alkaline batteries drop off in volatage, pretty quickly who knows how long it stays at 12V while in operation. 10NiMH batteries would have a flatter output, so holding the voltage at a steadier 12V would probably be different for the ballast.

Underwater Kinetics sells a NiCD battery pack (also 1.2Veach). I've read on another discussion board that the OEM NiCD battery pack has 8-C cells at 1.2V and 4.2Ah. UK lists the runtime at 2hours with this battery pack setup.

If you were to customize your own battery pack using D cells you would probably have a little more runtime. However, I don't know much about this area. The highest capicity rating i have seen for C-size NiMH 5000mAh and for D-size i have now seen 11.5A batteries. This should give you plenty more runtime.

I have also took apart my UKE LC100 down to it's ballast. If you are interested in studying it please go and see this thread: Guts of the LC100

The LC100 has several protective measures in place before its ballast can get any juice.

First it has a set of, customer replaceable, fuses. Inside the ballast housing are a set of Thermal circuit breakers and a pack of resistors. You can see them in the pictures.

I hope this helps you in your custom housing. Let me know if you ever plan on starting because i have an LC100 that would love a new body to live in. /ubbthreads/images/graemlins/grin.gif

You can easily adapt a Li-ion laptop battery to the inside of the LC100. You will have 11 V 6.5 Ah battery, and no risk of hydrogen build-up from Ni-MH.

Do not forget to re-use the battery charge / discharge circuit from the original battery.

You will have to find a way to make a water-proof battery recharging jack. I do not have one on mine. I just mimicked an 8C battery pack by using Li-Ions, and works very well for about 5 continous hours.

Anthony

One of the reasons I want to use the rechargable C or D
cells is, I want to be able to use regular battries if I
am not able to recharge them.
My trouble is, I still dont know if 8 C or D cells is enough
to drive 2 lc100 heads for a long enough time,
I dont want to have 2 power packs, I am trying to cut down
on the size and weight of my rig

HELP thanks in advance

If it is the welch allyn 10.2v ballast, it should not see more than 11v and not less than 9v. 4xAA nimh in parallell may be cheaper and lighter than a Dcell?