22
MicroController Control System
Systems Operation
Accessory Circuits
Horn Circuit
The horn will operate when the battery is connected
and the horn button is pushed. Current flows from
battery positive through horn fuse, horn switch and
horn, back to battery negative.
Hour Meter Circuit
Battery voltage is always supplied from Drive
controller DD-2 to the positive terminal of hourmeter
through seat switch. The negative terminal of
hourmeter go to battery negative.
DC-DC Converter Circuit
DC-DC Converter Circuit System
The DC-DC converter changes the lift truck battery
voltage to 12 volts. This 12 volts is used to power
accessories such as floodlights, brakes/side lights
and backup alarms.
The positive of the 12 volt output is common to the
positive of the battery voltage. The negative of the 12
volt output is pulsed to maintain a steady 12 volt
supply.
The 12 volt output of the converter is protected
against short circuits and overloading by an
internal 15 amp current limit circuit. A fuse on the
converter protects it from reverse connection of the
battery voltage.
Refer to Problem 28 in Troubleshooting section.
NOTICE
Do not connect the 12 volt negative output of the
DC-DC converter to battery negative. Damage to
system components could occur.
Summary of Contents for B20S-3
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