Hamilton Sundstrand Company Gas Fuel Metering Valve HFG2.0 Manuel D’Utilisation

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60 HFG2.0 
USER 
GUIDE
 
Watchdog expired 
The MCE watchdog timer continuously monitors the firmware program. 
Should the MCE firmware program stop functioning, or attempt to access 
an illegal address, the MCE signals a fault. 
This fault does not clear without RESET command. 
Resolver to Digital Converter (RDC) failure 
The MCE contains a resolver to digital converter chip (RDC) that provides 
position feedback information to the DSP. The RDC chip has on-board 
health monitoring.  
If the RDC detect an internal tracking error, a signal is sent to the MCE. 
Upon receipt, the MCE signals a fault. 
This fault does not clear without RESET command. 
Unregulated Voltage Low 
The MCE signals a fault if the reference voltage drops below minimum for 
ten (10) seconds
If the voltage returns to acceptable level, the fault signal is cleared. 
+/- 14V High/Low 
The MCE signals a FAULT if the internal 
±14 VDC power supplies 
exceed operating limits. This fault does not clear without RESET 
command. 
Input voltage High/Low 
The MCE signals a fault if the 120 VDC supply exceeds 180 VDC or 
drops below 75 VDC for more than 7.5 seconds 
  (1 second for 
). This fault clears when the 120 VDC supply voltage returns.