Technical experts at rotating electrics remanufacturer Autoelectro have issued some useful advice on the workings of its reversible alternator.

The introduction of the Stop-start Alternator Reversible System, or StARS, has been one of the key technological developments in this sector over recent years. Stop-start systems help reduce vehicle emissions and can mean fuel savings of 3% to 15% depending on the driving environment.

The StARS solution is a reversible alternator, which replaces the conventional alternator and starter motor to provide the combined function of the two components. The design allows the conversion of electrical energy into mechanical energy and vice-versa.

Later applications of conventional alternators would have their charge rate controlled by the vehicle’s ECU; whereas, the StARS has its own ECU which controls the reversible alternator.

On a manual vehicle when the ignition key is turned, the vehicle’s ECU will start the engine. This is achieved by the battery providing the required electrical energy; the reversible alternator then acts as a starter motor and starts the engine via an auxiliary belt. During normal driving conditions, the reversible alternator behaves as a conventional alternator by converting the mechanical energy into electrical energy and charging the battery.

Once the vehicle’s speed has fallen below 5mph, and providing the gearbox is in neutral and the clutch pedal is released, the StARS’ own ECU will command the engine to stop. Once the clutch is pressed and first gear engaged, the StARS’ ECU sends another order to the engine to start again.

The StARS has been incorporated on many vehicle applications since its inception, such as;

•     Citroën C4 diesel (2010-onwards)
•     Peugeot 308 diesel (2011-onwards)
•     Mercedes A and B-Class petrol (2005-onwards)
•     Smart Fortwo petrol (2008-onwards)

Autoelectro Sales Manager, Nick Hood, says that Autoelectro has established a range of reversible alternators for these and other vehicles and can often have product available which is difficult to source elsewhere.