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Warning:
If the battery is getting warm, that would indicate that it is full, and the power supply
should not be connected again - overcharging reduces the life of the battery.
Note:
After a recently fully charged battery is connected to the charger, it seems that it takes the
MAX712 about 30 min to sense that the battery voltage stops changing, and go to trickle
charge.
Examples:
Older PF-300:-
A 15 hour charge consists of 4.5 hrs of fast charge (400mA), followed by
10.5 hrs of trickle charge (50mA): 4.5*0.4+10.5*0.05=2.325Ah=3.5Ah*0.66, which fills the
battery to 66% of capacity (3.5Ah).
To fill the remaining 34% at 50mA takes 3.5*0.34/0.05=23.8hrs, +15hrs = 39hrs to 100%.
Assuming 20% losses:
(3.5Ah*20%)/50mA=0.7Ah/0.05A=14hrs of
trickle charge to cover losses, +39hrs=53hrs total.
In fact it needs ~9hrs * 0.4A = 3.6Ah to fill the battery from empty to 103% full capacity.
Assuming 20% losses:
(3.5Ah*20%-0.1)/50mA=0.6Ah/0.05A=12hrs of trickle charge to cover losses, +9hrs=21hrs
total.
A third session of fast charge would fill the last 17% in 3.5Ah*17%/0.4A=1.5hrs, = 10.5hrs
total.
Newer PF-300:-
4.5hrs fast: 0.8A*4.5h=3.6Ah = 90% of 4.0Ah
Slow: 10%= 0.4Ah/0.1A = 4h, total 8.5h to 100%
with 20% losses: 0.8Ah/0.1A = 8h
Total time fast and slow: 16.5hrs to 120%.
Fast only: 4.0Ah/0.8A=5hrs, +20%=6hrs,
that needs 2 sessions: 4.5hrs + 1.5hrs to 120%.
PF204, PF-SE & 216:-
1.2Ah/0.4A=3hrs to 100% capacity; with 20% losses
3h+20%=3.6hrs total.
This is well within the first 4.5hrs.
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