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7.3 EXPLANATION OF PARAMETERS
7.3.1 Shaft torque
The shaft torque is measured in the T(T)-Sense
®
rotor part and sent wireless to the control box. The shaft
torque output of the control box is connected to SPU3 via RS485 Modbus. *) **)
7.3.2 Shaft speed
The shaft speed is measured via a gravity sensor in the T(T)-Sense
®
rotor part and sent wireless to the
control box. The shaft speed output of the control box is connected to SPU3 via RS485 Modbus. *) **)
7.3.3 Shaft power
The measured torque and shaft speed are the input values to the power calculation, which is performed
in the T(T)-Sense
®
stator control box. The shaft power output of the control box is connected to SPU3
via RS485 Modbus. *) **)
7.3.4 Shaft thrust (option)
When a TT-Sense
®
is installed, which additionally measures shaft thrust, the measured thrust is sent
wireless to the control box. The shaft thrust output of the control box is connected to SPU3 via RS485
Modbus. *) **)
*)
Adjustment of the bar-graph-
ranges (“Engine Consumption” and “Engine Power”) and the
horizontal/vertical axis (“Propulsion Power/Speed diagram”) at the PEM4 touch screen are
programmed at VAF location.
**)
Zero torque adjustment will be done during commissioning of the T(T)-Sense
®
rotor and control
box. For more detailed information see section 6.4 of TIB-661 T-Sense
®
or TIB-664 TT-Sense
®
.
7.3.5 Shaft generator (option)
The shaft generator output signal should be an active 4
–20mA or Modbus signal. The input range is
programmed at VAF location.
The total power delivered by the main engine can be calculated by:
Total power main engine = Shaft power + shaft generator power.
Specific Fuel Oil Consumption (SFOC) value is calculated by dividing
the engine’s fuel consumption by
above mentioned Total power.
7.3.6 Fuel oil consumption
Up to 12 flowmeters, each with a pulse and temperature output, can be connected to the SPU3. The
SPU3 can handle a maximum of 8 engines and/or consumers. Please refer to section
pulse and temperature specifications.
The K-factor of each flowmeter is programmed at VAF location or can be set via the settings menu by
VAF authorised representatives through the PEM4 touch screen.
7.3.7 Fuel oil temperature
For an accurate calculation of fuel oil consumption, it is recommended to connect PT100 temperature
sensors within the system. Temperature sensors are strongly recommended when a supply/return
system is programmed. VAF type PT2 flowmeters are as a standard equipped with PT100 temperature
sensors. The PT100 sensors are connected to the SPU3.
The PT100 range is programmed in the SPU3. No further settings are needed.