[time-nuts] Sulzer 5A & 5P PSU/battery question

[Attila Kinali]

On Thu, 01 Nov 2012 21:51:21 +0100
Magnus Danielson <magnus at rubidium.dyndns.org> wrote:

> Yesterday I picked up a Sulzer 5A + 5P without batteries. It is supposed 
> to have 21 D-cell NiCd batteries, but today those are not easy to come 
> by,

NiCd Batteries still exist, but have been mostly replaced by LiIon/LiPoly
packs these days. Though, you should be still able to find NiMH batteries,
which are in most cases a drop in replacement for NiCd, if you keep
two things in mind:

1) The maximum charge current of the battery should never be exceeded.
NiCd were much more forgiving in that regard.

2) When charging finished, then the batteries need to be disconnected
unless you do a trickle charge. At least this was a problem with the
early NiMH, it might have changed in the past 15 years. Check datasheet.

3) Charge end detection for fast NiCd chargers (>1C) does not work with
NiMH as the negative Voltage slope of NiMH is not as pronounced as with
NiCd. If you have such a charger, you need to replace it with a modern one.


HTH

			Attila Kinali

PS: Yes, i cannot count :-)
-- 
There is no secret ingredient
         -- Po, Kung Fu Panda