SAMLEX AMERICA INC. | 23
The discharge curves in Fig. 7.1 show the % State of Charge versus the terminal voltage
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7.11 LOW DC INPUT VOLTAGE ALARM IN INVERTERS
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-
nals of the inverter has dropped to around 10.5V for a 12V battery (21V for 24V battery)
at C-Rate discharge current of C/5 Amps. Please note that the terminal voltage relative
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of 20%) for various discharge currents will be as given at Table 7.5 (Refer to Fig 7.1 for
parameters and values shown in Table 7.5):
TABLE 7.5 TERMINAL VOLTAGE AND SOC OF LOADED BATTERY
Discharge Current:
C-Rate
Terminal Voltage at 80% State
of Discharge (20% SOC)
Terminal Voltage When Completely
Discharged (0% SOC)
12V
24V
12V
24V
$"
10.45V
7
7
7
C/5 A
7
21.8V
7
7
C/10 A
7
7
11.00V
22.0V
C/20 A
11.85V
7
11.50V
7
C/100 A
12.15V
7
11.75V
7
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-
ger at around 80% discharged state (20% SOC) when the C-Rate discharge current is C/5
Amps. However, for lower C-Rate discharge current of C/10 Amps and lower, the battery
will be almost completely discharged when the alarm is sounded.
Hence, if the C-Rate
discharge current is lower than C/5 Amps, the battery may have completely discharged
by the time the Low DC Input Alarm is sounded.
7.12 LOW DC INPUT VOLTAGE SHUT-DOWN IN INVERTERS
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around 10.5V for a 12V battery (at around 21V for 24V battery) to warn the user to
disconnect the battery to prevent further draining of the battery. If the load is not dis-
connected at this stage, the batteries will be drained further to a lower voltage and to a
completely discharged condition that is harmful for the battery and for the inverter.
Inverters are normally provided with a protection to shut down the output of the inverter
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SECTION 7 |
General Information on Lead Acid
Batteries
