28V Alternator Controller
- Installation Drawing
- Warranty Card
- Product Eligibility Catalog (PEC)
- Troubleshooting Notes
- Instructions For Continued Airworthiness Maintenance (ICA)
Voltage Regulation, IC Sense reference
The Voltage Regulator keeps the bus voltage constant by increasing the current to the alternator’s field with a system load increase, decreasing it with a load decrease.
Field-to-Ground Fault Protection (GFP)
If the alternator’s field become shorted to ground, the GFP will deactivate the Voltage Regulator, and switch on the unit’s Red TSL, and the LVI light on the instrument panel.
Battery Off-Line Voltage Regulation (BOLR)
The design of the ACU allows it to excite the field of a rotating alternator (with a minimum residual voltage) and regulate the bus voltage with the battery off-line. This allows the system to carry electrical load if the battery or the battery relay fails.
Trouble-Shooting Light (TSL)
Green, Red, Off Alerts the user to the condition of the Alternator / ACU system. TSL: RED light with the Bat & Alt switches on means there is an internal or external ground short in the alternator field circuit. TSL: GREEN light with the engine running, means there is power coming out of the ACU. With the light Green, a bus voltage of 27.3 to 28.1V (for R25101 Rev A and R25102 Rev A , 28.4 to 28.8V) indicates a system that is operating correctly, and a sustained bus voltage of 20V to 25.6V means an open alternator field or field wire. Unless the ACU is damaged, the light should be Green when the master switch is on. TSL: Off with the Master switch on and no power to the ACU (red wire, pin 1), means that one power input device (like switch, circuit breaker, or wiring). If there is voltage on the red wire (pin 1) then the ACU is damaged.
- Increased Regulator life
- Reduced panel lights flicker
- Protects against grounded alternator field
- ACU controls & keeps the Alternator on-line if the Bat fails
- Identifies grounded field
- Reduce trouble-shooting time