GRAUPNER ULTRAMAT 14 PLUS Operating Manual page 32

N i C d b a l a n c e
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
o f f v o l t =
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
2
START
sec.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
* * I N F O R M A T I O N * * *
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
B A L A N C E R C O N .
2
sec.
B L C 2 8 : 3 0
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
N C + 0 . 0 0 A 0 7 . 7 1 7 V
NiCd-Delta-Peak (-∆ ∆ ∆ ∆ ∆ Peak) trigger voltage
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
N i C d d e l t a - p e a k -
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
v o l t = 1 0 m V / c e l l
+
INC
This process analyses the voltage peak of the charge curve, which indicates with great
accuracy when the maximum charge capacity is reached.When the charge process is started
the battery voltage initially rises continuously, but as the pack approaches full capacity it begins
to heat up. This in turn causes the battery voltage to fall slightly (Delta-V). The charger detects
and assesses the voltage decline.It is possible to adjust the sensitivity, or trigger voltage (in mV
per cell!) of the automatic cut-off circuit for Ni-Cd batteries. A practical range of values has
proved to be 10 ... 30 mV / cell. Higher voltages often lead to overcharging of the battery,
whereas a lower voltage tends to result in premature termination of the charge process. We
recommend that you check the information supplied by your battery manufacturer, then carry
out a series of test charges to establish the optimum value for your battery. Start with 10mV/cell
to avaid overcharging the battery.
32
NiCd discharge balancing program
The balancing program does balance up to 6 cells of a battery
pack.
The final discharge voltage for the balancer can be set
c u t
within the range 1.20 ... 1.30 V using the INC or DEC
1 . 2 0 V
button.
The individual cells in a battery should be balanced before
+ -
the pack is charged, to avoid the possibility of individual
INC
DEC
cells being overcharged during the charge process. A
battery should always be balanced before being charged
if it has been stored for a considerable period;
connect the balancer plug to the charger to carry this out.
It is also essential that the voltage of each cell in the pack
should be higher than the set balancer final discharge
voltage.
If you wish to obtain maximum battery capacity, the
individual cells should be discharged to 1.20 V a few hours
- but no longer than two hours - before the next charge
process. If the voltage falls below 1.20 V, the battery cells
lose capacity, so the pack must be charged to around
60% capacity before being stored for a protracted period.
0 1 4 2 5
The program balances the battery pack. Cells with a
higher cell voltage are discharged at around 100 mA
(balancing current). The charger terminates the discharge
balance process once all the cells have reached the
balancer final discharge voltage (+0.01 V).
The automatic charge termination
circuit (battery full detection) works on
the proven Delta Peak principle (also
known as the Delta-V process), which
-
is already in use in millions of chargers.
DEC
charging time