Lotus Service Bulletin: Alternator Type 17ACR

Class = 111
Number = 1973/06
Type = All +2
Date = 02.04.73

Title: Alternator Type ‘17ACR’
Reason: To advise Dealer personnel of changes incorporated in manufacture to the Type ‘17ACR’ alternator.
Parts Required: B050 E 6007Z - Alternator
Action:
  1. The Lucas Type ‘17ACR’ alternator, now incorporates an ’ avalanche ’ diode against surge which occurs in the regulator. The regulator is simplified, now having fewer separate semi-conductors, and is designated ‘14TR’ . The regulator is still built in to the alternator.
  2. Interchangeability is unaffected by the above statement.
  3. The advantage of an ‘avalanche’ diode is that it provides a diversionary path for the surge energy and limits the voltage appearing across the field/regulator circuit to between 22 and 32 volts, a value which is well below the minimum breakdown voltage of the output transistor.
  4. For Dealers who require further information on the foregoing, booklets ‘EI . 17’ for Regulator and ‘El .20’ for Alternator, are available from:Joseph Lucas (Electrical) Ltd, Birmingham, England.