[Sketch notes: The starting air system consists of: (1) air compressors (main and standby); (2) air receivers (bottles) with safety valves, drain valves, and pressure gauges; (3) a main starting air line to the engine; (4) a main starting air valve (shut-off valve); (5) the air distributor and the starting air valves on the engine cylinders; (6) a non-return valve and a relief valve; (7) a pressure-reducing valve for control air.]

The starting air system: air compressors charge the air receivers to the working pressure (e.g. 30 bar). The air is stored in the receivers. For starting, the main starting air valve is opened and the air is admitted through the main line to the air distributor, which directs the air to the starting air valves of the cylinders in the correct order, turning the engine. When the engine fires, the starting air is cut off. The system has safety valves on the receivers, drain valves to remove water/oil, and a non-return valve to prevent back-flow. A pressure-reducing valve supplies control air for the pneumatic controls.

When an auxiliary engine (generator) is under the control of the Power Management System (PMS), the following precautions/conditions must be observed:

1. The engine must be in a condition to start automatically (ready for automatic start) - the starting air (or starting system) must be available and the engine must be in good condition.
2. The engine's protection systems (overspeed, low oil pressure, high water temperature, etc.) must be operational.
3. The engine must be able to accept the load automatically (the governor must be set for automatic load sharing).
4. The fuel supply must be available and the engine must be able to start and run.
5. The PMS must be able to start, stop, and load/unload the engine automatically based on the electrical load.
6. The engine must be monitored (alarms) and the PMS must respond to faults.
7. The engine must not be started if it is under maintenance or if the interlocks (e.g. turning gear) are engaged.

When the PMS detects that the electrical load is approaching the capacity of the running generators (or a generator is needed), it initiates the automatic start of a standby generator:

1. The PMS checks that a standby generator is available and ready (starting air/fuel available, no alarms, interlocks clear).
2. The PMS sends a start command to the generator's starting system (e.g. opens the starting air valve or energizes the starter).
3. The engine is started (by starting air or electric starter) and accelerates to its rated speed.
4. The PMS checks that the engine has reached the correct speed and is ready to accept load.
5. The PMS synchronises the generator with the bus (matches voltage, frequency, and phase) and closes the breaker.
6. The PMS then loads the generator (increases the fuel) to share the load with the running generators, according to the load-sharing settings.
7. The PMS monitors the generator and the load, and will start/stop generators as the load changes.

The PMS thus provides automatic, unattended starting and load management of the auxiliary engines.