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Alternators - LUCAS: Description

Lucas "ACR" model alternators have an integral voltage regulator mounted in the slip ring end bracket. The stator consists of star-connected, three phase windings on a ring end cover and drive end bracket. The rotor is either an eight or twelve pole type with the field windings connected to two face-type slip rings, and is supported in drive-end bracket by a ball bearing and in the end cover by needle roller bearings. One positive and one negative carbon brush ride against concentric brass slip rings. The heatsink-rectifier, terminal block assembly incorporate six silicon diodes, forming a full wave rectifier bridge circuit, and three diodes which supply current to the rotor windings.

NOTE: Up to a ten milliamp battery drain is normal, even with the ignition in the "OFF" position.
APPLICATION

Model  Type No. 
Austin Marina 18 ACR
Jaguar  
  XJ-6 Without Air Cond. 18 ACR
  XJ-6 With Air Cond. 20 ACR
  XJ-12 20 ACR
MG 16 ACR
Triumph  
  Spitfire 1500 16 ACR
  TR-6 18 ACR
  TR-7 20 ACR
SPECIFICATIONS

Nominal Output 
Alternator  Amps @ RPM  (1) Voltage 
16 ACR 34 @ 6000 12
18 ACR 43 @ 6000 12
20 ACR 66 @ 6000 12
Fig 1: Disassembled View of Lucas Integral Regulator Alternator Assembly
G09350237Courtesy of NOT AVAILABLE