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Old October 19th 06, 07:35 AM posted to rec.radio.amateur.equipment
Ed Ed is offline
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First recorded activity by RadioBanter: Oct 2006
Posts: 1
Default Maha MH-C777Plus Charger Question

Hi Joe:


Maha MH-C777Plus II

Supports Ni Cad, Ni Metal Hydride, and Lithium Ion/Polymer chemistries only!
---------------------

Using Ni chemistries of 1.2v/cell or more (AA, AAA, C, or D or equiv.
rechargeable battery pacs or cells)

Charge + Trickle function: 1 to 12 cells in series. [1.2v to 14.4v]


Also Analyzes (Discharge and hold function only) 3 or more cells only
(No 1.2/2.4v cells alone)


Also Conditions (Discharge + Charge + Trickle function) 3 or more cells
only. (No 1.2/2.4v cells alone)

------------------------

For the analyzing function, it need a minimum of 3 cells to determine
battery quality. I.E., Good, Shorted, Leaky, Reversed Polarity w/in a
cell, etc.

You cannot do the discharge function if a battery pac has internal
protection diodes, but you can do the charge!

If charging an expensive Ni battery pac for the first time, do monitor
the total output in Ma/Hr, especially during the 90% to 115% period of
rated capacity for excessive heat buildup.

Note: the first charging cycle on brand new batteries is likely to not
fully charge the battery. Subsequent charging cycles will be more
uniform and approach full at ~115% of rated capacity.

Although the charger monitors delta T & delta -V, the cell covering
construction, cardboard, film or plastic pkg can fool the T sensor.

Avoid charging cells w/ low factory capacities, like 400Ma/Hr or less!
Avoid mixing batteries or those w/ different histories!

Long term trickle charging Ni-Cads will build-up internal xtal size,
resistance and subsequent "memory". Use the Re-condition cycle on such
Ni-Cads every 2 months or so.

I recommend this unit for techies who have time to learn the technology
and monitor this Maha with its fast advanced charging cycle. [800Ma +/-
50 for Ni chemistry]

Hope this helps.
Bye.
Ed.