Planet ES-10024B-1 Maintenance Manual page 34

3.2 Continued
Failed battery: Determine battery age and check for expected life. If near or beyond normal life, replace battery.
If battery discharges frequently, check for dead or shorted cells, if found replace battery. Voltage regulator
set too high for aircraft operating conditions: Check the voltage regulator setting per the aircraft service
manual. Adjust if necessary. If adjustment is not possible, check the wiring harness before replacing the voltage
regulator.
Ground wire loose or broken between regulator and alternator: If wire is broken, make sure there is
adequate strain relief and clear chaffing areas. Repair or replace wire. If loose, tighten connection.
Shorted cell in battery causing other cells to use water excessively: Remove and place battery on battery
tester to verify the condition. Replace failed battery.
Shorted voltage regulator output - full field condition: Before replacing the voltage regulator, check wiring
harness for shorts or open conditions. If harness is burnt or shows signs of overheating, replace harness. If,
wiring is good replace voltage regulator.
Voltage drop in voltage regulator feedback circuit: The "feedback" line is commonly known as the sense line.
Before replacing the voltage regulator, check sense line wire for resistive or short conditions. Check terminal
connections, replace or repair wire if bad. If, wiring is good replace voltage regulator.
Alternator output above rating: As output is related to alternator speed, check that the proper alternator has
been installed. Check airplane records to determine that the proper alternator model and rating is installed per
the aircraft TC or STC.
Failed bearing: To perform a test for failed bearings, hold the alternator in one hand and snap-spin the shaft with
the other. A failed bearing will be heard or felt. Replace the bearing by overhaul or replacement of the alternator.
24-30-01
Page: 3-4
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Aircraft Alternator
Maintenence Manual
Table 3.3
Rev. A: 11 Aug. 2021
ES1031