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Charging indicator lamp

Charging indicator lamp

The charging indicator lamp tells the driver whether the generator is charging or not.

When the ignition switch is in drive position (ON), B+ is fed to the charging indicator lamp in the main instrument unit and then on to the generator.

When the generator is not rotating or if it is not charging the battery for any reason, the charging indicator lamp circuit will be grounded through it, causing the lamp to light up.

When the generator is charging, the D+ terminal receives the same voltage as B+. The charging indicator lamp will then be getting a voltage feed on both terminals and will go out.



Important

Since the generator's excitation is built up through the bulb the rating of the latter (2W) must not be changed, since this would affect the excitation voltage.


To further increase the field excitation and prevent it from disappearing completely if the bulb should fail, there is also a resistor connected in parallel with the bulb.

A diode connected in series with the charging indicator lamp prevents the bulb from glowing when high charging currents are passing.