The following safety shut-offs are detected:

• Extraneous light test during the purge phase

  The flame inputs are monitored for extraneous light during the purge phase for the duration of the adjusted minimum test time.

• Ignition flame not formed

  The flame detection system has not detected an ignition flame within the 1st safety time.

• Ignition flame fault

  The ignition flame has gone out.

• Main flame fault

  The main flame hasn't formed or has gone out.

• Extraneous light test after burner OFF

  The flame detection system is detecting a flame after the main fuel valves were already closed. The function can be activated via the parameter Extraneous light: Monitoring after burner OFF.

• Ignition flame extraneous light

  If a separate flame detection system is used for the ignition flame on flame input 2, then it is monitored for extraneous light before the ignition flame is switched on. Monitoring of the ignition flame can be deactivated via the Ignition flame extraneous light: No monitoring during burner operation parameter.

  The system behaves as follows, depending on the use case:

  • Blow out

    The flame detection system must not detect any extraneous light for the duration of the adjusted minimum test time before the ignition flame is activated. A safety shut-off occurs if extraneous light is detected.

  • Pilot Burner Function

    The flame detection system must also not detect any extraneous light before the pilot burner function is activated. If extraneous light is detected, then an alarm message is displayed and the pilot burner isn't activated.