TIAH64D MPU-24
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3
Operating Procedures
3.10– Regulated AC Power
Plugging in with AC Power
When the TIAH64D MPU-24 is plugged into ac power, the output is 28.5 volts. This voltage allows the system
to recondition and recharge the aircraft’s battery(s). It is also an optimum voltage for powering avionics and
lighting on most aircraft. The MPU’s ac to dc converter produces continuous amps of dc power depending
on the size of the system.
Ensure 120 or 240 Vac power cord is properly connected to an approved ac power supply. After approximately
5-8 seconds, unit’s LED status indicator will illuminate indicating power cell state of charge. Cooling fan will
operate. Ensure LED status indicator and cooling fan is operational prior to continuing.
Figure 3.10.1 Connecting TIAH64D to AC Power Supply
Connect DC Power To Aircraft (Low Power Demand)
Low power demand is defined by a requirement of 10 amps or less. Connect dc power to aircraft ground
power receptacle. DC bus power should come on and aircraft voltmeter should indicate 28.5 Vdc to 27 Vdc
(26.5 Vdc minimum). If aircraft power demand is less than 10 amps converter output will remain at 28.5
Vdc (only one GREEN LED status indicator bar will illuminate). If aircraft power demand exceeds 10 amps
converter voltage output will decrease and two or more LED status indicator bars will illuminate.
Figure 3.10.2 TIAH64D MPU-24 connected to dc power
