4
2.
SYSTEM DESCRIPTION
2.1 PEM4 Propulsion Efficiency Monitoring System
The PEM4 system is a modular propulsion efficiency system. This manual describes the combination of
the PEM4 with the SPU3 (Signal Processing Unit). The PEM4 stand alone system is able to calculate
torque, speed and power output data. The PEM4 stand alone is described in a separate technical manual,
(TIB-669 T-Sense
®
and PEM4 stand alone). The PEM4 system in combination with the SPU3 can
manage a maximum of 12 Flowmeter inputs in with PT100 temperature inputs related to a maximum of
8 consumers. Furthermore a maximum of 6 ViscoSense
®
3D inputs, a speed log pulse, GPS NMEA
signal, draft meter and inclino meter can be added as input to the system.
The SPU3 converts all these input signals to one RJ45 Ethernet signal for monitoring purposes through
a PEM4 touch screen or using the IVY
®
Propulsion Performance Management system.
A RS485 Modbus signal is available for connection an external system like Alarm and Monitoring System
(AMS) or to connect a separate PC running the optional SPU3 datalogger software.
Functions, which can be performed with the PEM4 + SPU3 system are:
•
Measurement and display of the torque, thrust, shaft speed and power.
•
Calculation of the average shaft power, shaft speed and torque during the last 1, 4 and 24 hours.
•
Calculation of the total energy, total revolutions and total CO
2
emissions including reset.
•
Calculation of the fuel consumption in kg per nautical mile, fuel consumption in kg per hour, fuel
consumption in gram per kWh (
Specific Fuel Oil Consumption - SFOC
), average fuel consumption per
nautical mile, fuel temperature compensation and calculation of the total mass per fuel type per
consumer including reset.
•
Calculation of thrust, thrust power quotient, when a TT-Sense
®
sensor is installed.
•
Displaying of parameters, engine load diagram and power/speed diagram.
•
Above mentioned calculations for twin screw vessels when an additional T-Sense
®
or TT-Sense
®
system is installed.
The SPU3 can be installed in the vicinity of the flow meter(s) and/or booster unit or in the engine control
room (ECR). The PEM4 touch screen can be installed in a control cabinet or control panel in the ECR
and/or on the bridge.
2.2 SYSTEM SECURITY
Besides checking the status of the torque measurement system and/or flowmeters the PEM4 + SPU3
system also checks itself continuously for program and configuration data integrity, normal program flow
and power supply conditions. All alarm messages will be logged in a dedicated alarm screen.