Hamilton Sundstrand Company Gas Fuel Metering Valve HFG2.0 - Manual (Page 69)

APPENDIX B: GLOSSARY
Term Definition
RUN Command A discrete 24 VDC signal that enables the HFG2.0 actuator and valve
to move.
RESET Command A discrete 24 VDC signal that causes the HFG2.0 internal program
(firmware) to jump to the beginning.
Controller A user-provided computer that executes commands to the HFG2.0
and accepts analog and discrete feedback.
Fuel Demand A 4 mA to 20 mA signal that commands the HFG2.0 to move to a
certain actuator/valve position. The signal is scaled with SPAN.
Position Demand Feedback A 4 mA to 20 mA signal that communicates the actual HFG2.0
actuator/valve position to the controller.
Motor Current Feedback A 4 mA to 20 mA signal that is proportional to the HFG2.0 motor
current. The signal is scaled with Max. Force.
FAULT alarm A discrete signal from the HFG2.0 that communicates an internal
failure. The user’s controller will see an open circuit when a FAULT
alarm is active.
OVERTEMP alarm A discrete signal from the HFG2.0 that communicates an internal
over temperature; electronics or motor. The user’s controller will see
an open circuit when the OVERTEMP alarm is active.
HOME A mechanical rigid stop from which the HFG2.0 calculates position.
HOME is found at start-up during the Homing sequence. The HFG2.0
defines HOME when the motor current exceeds the HOMING
FORCE and velocity is zero. HOME is defined as the actuator/valve
position when the Demand signal is 4 mA. HOME is the Valve Closed
condition for the HFG2.0
Homing sequence When the HFG2.0 extends or retracts to find a rigid mechanical stop.
SPAN Maximum distance from HOME. SPAN is defined as the position
when the Demand signal is 20 mA.
STOP position A user-defined position between HOME and SPAN that the HFG2.0
travels to upon loss of RUN or position Demand signal.
Maximum Velocity A user defined maximum velocity in inches per second.
Maximum Homing Force A user defined maximum homing force output setting. The motor
control electronics uses this setting to determine the maximum motor
current in the Homing sequence.
Maximum Holding Force A user-defined maximum force while in the Holding Motor Current
state.
APPENDIX C: GLOSSARY 63