Hamilton Sundstrand Company Gas Fuel Metering Valve HFG2.0 User Manual

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during the RESET command. To reset the HFG2.0, +24 VDC must be 
applied across the RESET wires for at least 0.5 seconds in order to reset 
the controller and actuator. 
DEMAND Signal 
The DEMAND signal is a user-provided analog input that is used to 
control the position of the valve. The current level of the DEMAND signal 
is correlated to the position of the valve within its range. The minimum 
Demand signal of 4.0 mA is correlated to the CLOSED (Home) position. 
The maximum Demand signal of 20 mA is correlated to the OPEN 
(maximum flow) position. 
Feedback Signals 
The HFG2.0 provides two two-wire feedback signals via the integral 
17-wire signal harness. Refer to Figure 1-14 for typical connections. Refer 
to the General Specification Summary Table in Section 1.2 for feedback 
specification values. 
Position Feedback 
The HFG2.0 provides analog valve position feedback to the user. This 
internally-generated feedback signal is proportional to the valve position. 
A signal level of 4 mA represents that the valve is at its CLOSED (Home) 
position; while a signal level of 20 mA represents that the valve is at its 
maximum span. 
Motor Current Feedback 
The HFG2.0 provides motor current feedback. This internally-generated 
feedback signal is proportional to actuator load. A signal level of 4 mA 
represents no load on the actuator; while a signal level of 20 mA is the 
maximum load. 
 
CH. 2: UNDERSTANDING THE HFG2.0 
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