Printronix L5000 Series Maintenance Manual page 259

Alarm
This signal indicates that an abnormality has occurred. When an abnormality occurs,
the voltage between the collector and emitter of the interface circuit transistor
becomes "H."
Abnormalities that cause the alarm signal:
Abnormality in charge voltage
Abnormality in temperature/temperature of resistor for discharge
Flash error
Charge time late
Charge status
This signal indicates that the power supply unit for the flash has been charged.
When charging is completed, the voltage between the collector and emitter of the
interface circuit transistor becomes "H."
Logic power supply +
This is the positive side of the logic unit action power supply.
Logic power supply –
This is the negative side of the logic unit action power supply.
Drive power supply +
This is the positive side of the lamp drive power supply.
Drive power supply –
This is the negative side of the lamp drive power supply.
Electrical and Wire Data 6–21