TecJet 110 Fuel Metering System
Manual 26185
10
Woodward
Chapter 3.
Description of Operation
External fire protection is not provided in the scope of this product. It
is the responsibility of the user to satisfy any applicable
requirements for their system.
Due to typical noise levels in engine environments, hearing
protection should be worn when working on or around the TecJet™
110.
The surface of this product can become hot enough or cold enough
to be a hazard. Use protective gear for product handling in these
circumstances. Temperature ratings are included in the specification
section of this manual.
Configuration
The valve can be configured to accept a flow demand from the analog input, the
PWM input, or the CAN port. The configuration also includes user adjustable
warning limits, and default values for failed sensor backup modes. The
configuration can be viewed or changed using the TecJet Service Tool. See
Chapter 6 for information on installing the service tool.
Power-on Procedure
When power is applied to the valve, it performs a diagnostic check. If there are
no problems detected, the actuator is enabled with 1.1 N
x
m (0.8 lb-ft) of torque,
and the valve closes. If the flow demand source is configured for EGS CAN or
Jenbacher CAN, the valve reads the CAN ID input pins and begins sending
diagnostic information on the CAN link. If a problem is detected, the valve will not
operate and the status output will indicate a fault.
The TecJet 110 is typically continuously connected to the supply voltage. If the
flow demand source is configured to Jenbacher CAN, the key switch has no
effect. If the flow demand source is configured for anything else, the key switch
input must be connected to a high signal (supply [+]) for the valve to operate.
When the key switch is off, the valve closes, if possible, and the actuator that
positions the valve is disabled to minimize the amount of current drawn from the
battery.
Normal Operation
If a valid flow demand is present, the valve begins normal operation. The TecJet
110 calculates the area needed to provide the requested flow. This area is
calculated using the delta pressure (inlet to outlet pressure differential), the
absolute inlet fuel gas pressure, the fuel gas temperature, the fuel gas ratio of
specific heats (K), the fuel gas density, and the calibration information stored in
the valve. The actuator positions the valve to achieve the calculated area
requirement.