47-20-09 ERCO: (Was Service Note 1 of AD-718-6.) Applies to 415-C, -CD and -D Aircraft.
Compliance required at each 100-hour inspection and immediately after each electrical system malfunction.
Check the operation of the voltage regulator by observing the ammeter reading after starting and until the battery becomes charged. A normal operation would indicate a charging rate up to 11-13 amperes for periods of time up to 20 minutes after starting. The charging rate should reduce to 2 amperes or less within 2 hours or operation.
(Ercoupe Service Department Memorandum No. 23 covers this same subject.)