Toshiba T-Series T4500, User Manual

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Figure 1-13 Main Battery Circuit (Nickel Metal Hydride)
The T4500/T4600 Family’s main battery has three devices to prevent circuit overload. Table 1-9
shows the overload specifications.
Table 1-9 Circuit Overload Protection Devices for Main Battery
(Nickel Cadmium/Nickel Metal Hydride)
Protection Method Rating/Function
➊
Thermal protector
Electrical rating 12 VDC, 3 A
Maximum circuit breaker current 12 VDC/120 A
Allowable operating temperature 60° ~ 75°
➋
Thermal fuse
Current rating 10 A
Voltage rating 250 V
Temperature rating 91° C
➌
Thermal sensor (Monitors the battery’s temperature)
Load resistance 10 k
Ω
±1% (at 25° C)
Operating temperature limits -50° ~ 100° C
➊
Thermal protector
When the temperature falls outside the operating range of 60° to 75° C, the thermal protec-
tor reduces the current by increasing the internal resistance.
➋
Thermal Fuses
If the temperature exceeds 91° C, the thermal fuses may blow to protect the battery and the
system.
WARNING: Never try to use a battery unless its fuses are intact. Do not try to replace a
battery fuse or try to bypass a fuse. Using a defective battery can permanently damage the
system and can cause injury.
➌
Thermal sensor
The thermal sensor monitors the temperature of the battery.
➍
T line
The thermal sensor monitors the temperature of the battery and changes the voltage in the T
line accordingly. The power supply microprocessor monitors the voltage changes in the T