Generator — General Information (Focus Turnier 1)

The generator is a compact power plant. When the engine is running, it supplies all electrical units with electricity and constantly charges the battery with excess electricity. In Focus with an engine capacity of 1.4 and 1.6 liters, 14-volt three-phase generators with a power of 70 A operate, with an engine capacity of 1.8 liters and more - 14-volt three-phase generators with a power of 90 A. They are driven by poly V-belts and rotate at a frequency that is approximately twice the engine speed. Three-phase generators produce alternating current, which is converted into direct current by a rectifier integrated into the housing. The required on-board voltage is limited by a voltage regulator installed on the rear side of the generator. The generator charges the battery and simultaneously supplies electricity to all included electrical consumers.

Protects the battery by regulating the charging system with PCM

Cold batteries are most effectively recharged with increased voltage, hot batteries, on the contrary, with reduced voltage. Ford takes this fact into account in the Focus by using expensive regulation: the charging system is supervised by the powertrain control unit (PCM). It adapts the charging voltage using the signal from the intake air temperature (IAT) sensor to the current battery temperature. To do this, it calculates the most appropriate voltage target value and sends it via a communication link to the regulator.

At the same time, the PCM controls and monitors the output generator. If the current consumption is high or the battery is discharged, the system increases, for example, the idle speed. In order to minimize the load on the engine (starter, battery) during start-up, a slipping clutch inside the generator (external in diesel) disconnects the belt pulley from the anchor shaft: the generators in the Focus start working in excellent shape if the engine is running. Then the PCM constantly increases the generator power with the help of the mentioned coupling clutch. Do not try to repair failed generators in the Focus - this is a typical case for a workshop.