SECTION 06: ELECTRICAL
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version) – Sec 06 revised June 2017
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3. PRIME ENERGY MANAGEMENT
SYSTEM
The acronym “prime” stands for power recovery
by intelligent management of energy.
This system focuses on eliminating parasitic
loads on the engine by intelligent management
of the alternators and air compressor duty cycle.
Instead of constantly charging, the alternators
will use engine negative torque (braking,
deceleration) to generate “free” electricity.
Depending on the compressed air requirement,
prime will also trigger the production of
compressed air on negative torque.
Prime also introduces maintenance-free
absorbed glass mat (agm) batteries and a new
vanner 80 series battery equalizer that monitors
battery state of charge (soc).
Battery temperature, voltage and current are
also monitored to prevent overcharging and
overheating.
Maximum fuel economy is obtained on a ride
when the mix of hilly and flat portions allows the
batteries to be charged when the vehicle is in
free wheel. It basically means that batteries are
charged with free energy and that no fuel
consumption is dedicated to charge the
batteries.
3.1 COMPONENTS
New components includes agm batteries, an 80
series vanner battery equalizer, a temperature
sensor located on the battery post and two
voltage and current sensors monitoring 12v and
24 v circuits.
Refer to Figure 22 below.
The compressor duty cycle control is achieved
by an electric air dryer. This is covered in
section 12 of this manual.
FIGURE 22: PRIME ELECTRICAL COMPONENTS
