Canon Transistor Pack E w/nicad battery

dhlewis

[FONT=Geneva, Verdana, Arial, Helvetica, sans-serif]Hi picked up a used one of these used recently for a good price and have a couple of questions. I know that this design is pretty old but the one I have is like brand new and I figured I could always convert it to the C battery tray if the NiCad battery dies.

I used it once and appears to be working as my recycles were pretty fast. If anyone has the NiCad battery how often do you recharge it. The only information I have is that you should always charge it for a full 15 hours.

If you have the cord plugged into the external battery pack and the strobe (580EX) will the flash only fire if there is power in the external NiCad battery? I know the AA batteries in the strobe switch and are used only to power the LCD but what happens if the external pack is dead and plugged in the strobe will not fire? I would assume that the CP-E2 and CP-E3 work the same way?

TIA,

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ziggy53

dhlewis wrote:

[FONT=Geneva, Verdana, Arial, Helvetica, sans-serif]...

I used it once and appears to be working as my recycles were pretty fast. If anyone has the NiCad battery how often do you recharge it. The only information I have is that you should always charge it for a full 15 hours.

If you have the cord plugged into the external battery pack and the strobe (580EX) will the flash only fire if there is power in the external NiCad battery? I know the AA batteries in the strobe switch and are used only to power the LCD but what happens if the external pack is dead and plugged in the strobe will not fire? I would assume that the CP-E2 and CP-E3 work the same way?

TIA,

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I don't have that particular unit, but I think I can answer some of the questions based on my experiences with similar units.

First, NiCd (NiCad) batteries should be fully cycled, but not absolutely completely dead, before recharging. This means you should run them until they no longer charge a flash to full, or when they are reaching ridiculous cycle times. If you short-cycle the batteries, charging before a full discharge cycle, you can run into the dreaded "memory effect", which appears to be a buildup of crystals in the electrolyte. Short cycling once may not cause problems, but repeated short cycling usually does.

12 - 15 hours is about normal charge time and NiCd batteries are not too vulnerable to overcharge. (It generally doesn't hurt to charge 24-36 hours, but it doesn't help either.) If the batteries are warm after 15 hours, I would remove them.

You might consider using NiMH (Nickel Metal Hydride) batteries instead, if you build your own pack. They have the same voltage as the NiCd, so use the same amount of batteries, but less of the charging problems and a higher power density.

It is my understanding that the AA batteries also operate the control circuits of the flash.

ziggy53