Fuel Used Indicator

  1. Item 9 +12 : Fuel used – Engine 1&2
  • This digital value, resulting from fuel flow integration inside DMC, can vary from 0 to 4536 0 KG, with 10 KG resolution.
  • The engine identification number is in amber, when the engine is below idle. It is in white, when it is at, or above, idle.
  • The fuel used indication is green from flight phase 2, until electrical power is cut off at the end of the flight. It is automatically reset, when the engine is started on ground.
  • Case 1: It is normally displayed in green.
  • Case 2: In case of degraded data (if indication of fuel flow is not valid in flight after 60s) , all the digits are dashed, together with the TOTAL indication (FUEL USED 1+2) with two horizontal amber lines (fuel flow value from the FADEC bus not correctly received by the DMC in flight).
  • Case 3: It is replaced by amber XX after a long DMC power supply interruption in flight. In this case, the fuel used computation stops untill next starting sequence on ground. As a result, the total fuel used is also replaced by two amber XX.

2. Item 11 : Total Fuel Used

A total fuel used is computed:

  • and normally displayed in green (case 1).
  • As soon as one (at least) of the two fuel used values is dashed (degraded data), then the total fuel used is also dashed (case 2)
  • As soon as one (at least) of the two fuel used values is replaced by amber XX, then the total fuel used is also replaced by amber XX (case 3).

3. Fuel Flow indication

  • The Total Fuel Flow is displayed in kg/mn.
  • It is normally in green , It is replaced by an amber XX if there is no valid data.
  • The fuel flow transmitter signal is fed to the FADEC which processes it and transmits the information to the ECAM system for display

  • DMC circuit breaker
  • FADEC :
    • Each powerplant has a FADEC (Full Authority Digital Engine Control) system.
    • FADEC, also called the Electronic Engine Control (EEC), is a digital control system that performs complete engine management
    • FADEC has two-channel redundancy, with one channel active and one in standby.
    • The system has a magnetic alternator for an internal power source.
  • The EEC is designed to operate with the engine not running, the EEC is operational five seconds after it is electrically powered by A/C 28VDC. The EEC is electrically powered by the A/C through the EIU. That A/C 28VDC permits :
    • automatic ground check of the FADEC before engine running
    • engine starting
    • powering the EEC (while engine is running below 10 % N2).
  • As soon as the engine is running at and above 10 % N2 rpm, the dedicated alternator ( magnetic alternator) provides electrical power for the FADEC system.
  • After an engine shut down the EEC is powered by A/C 28VDC for 5 minutes to allow engine parameters monitoring.
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