METREL MI 3290, Инструкция по эксплуатации

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MI 3290 Earth Analyser Safety and operational considerations
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Typical charging profile which is also used in this instrument is shown in Figure 2.4 .
I
CH/8
Fastcharge Safety Time
Precharge
Time
Current Regulation Voltage Regulation
I
CH
V
REG
V
LOWV
Charg
e
Curre
nt
Charg
e
Volta
ge
Figure 2.4: Typical charging profile
where:
V
REG
................................... Battery charging voltage
V
LOWV
.................................. Precharge threshold voltage
I
CH
...................................... Battery charging current
I
CH/8
.................................... 1/8 of the charging current
2.2.1 Precharge
On power up, if the battery voltage is below the V
LOWV
threshold, the charger applies 1/8 of the
charging current to the battery. The precharge feature is intended to revive deeply discharged
battery. If the V
LOWV
threshold is not reached within 30 minutes of initiating precharge, the
charger turns off and a FAULT is indicated.
Figure 2.5: Battery fault indication
(charging suspended, timer fault, battery absent)
Figure 2.6: Battery full indication
(charging completed)
Note:

As a safety backup, the charger also provides an internal 5-hour charge timer for fast
charge.