The other actuators will continue to control the fuel pressure. At less than the medium load, the
pressure relief valve releases unwanted fuel.
6.2.3.1.5
Monitored items
The fuel pressure is monitored. If the pressure is out of the tolerance, a failure indication shows.
The pressure transmitters PT3431-37C are installed on the accumulators downstream from the
fuel pumps. These pressure transmitters are connected to the IOM-10 and send the pressure
value through a bus communication line to the WECS-9520. If the pressure value is not in the
set range, the related fuel pump actuator will move to zero supply.
If a pressure transmitter becomes defective, its signal indication disappears but an alarm is
activated.
When the function to monitor the fuel is activated, the fuel pump actuator status is activated.
The signals that follow are monitored for each fuel pump actuator:
•
Feedback position 4 mA to 20 mA (XI5046-49C)
•
Active failure digital input (XS5046-49C).
6.2.3.2
Servo oil pressure setpoint
6.2.3.2.1
Pressure setpoint
Each servo oil pump has an internal mechanical pressure controller with an electrical setpoint. A
pulse width modulation (PWM) signal gives this setpoint.
The setpoint is related to the engine load.
A closed loop control adjusts the pressure in the servo oil rail.
Each pressure controller in the servo oil pumps is connected to an FCM-20 on cylinders No. 3,
No. 4 and No. 5.
6.2.3.2.2
Emergency mode
If one servo oil pump becomes defective, the system will continue to operate. The other servo
oil pumps will continue to supply the necessary pressure to the servo oil rail.
6.2.3.2.3
Monitored items
The pressure is monitored. If the pressure is out of tolerance, a failure indication shows.
The sensors are monitored. If the sensors are out of range, a failure indication shows and the
related LED will flash on the FCM-20 of cylinders No. 1 and No. 2.
6.2.3.3
Cylinder oil system - control
The FCM-20 control the functions of the cylinder oil system. The dual circuits of the system bus,
CAN bus and power supply make sure of redundancy.
X92DF
AA00-0000-00AAB-043K-A
Operation Manual
Engine control system WECS-9520
Winterthur Gas & Diesel Ltd.
- 262 -
Issue 002 2020-08
