AUTOFLAME Mk8 MM, Technical Manual

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2 Flame Safeguard
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MM Application Possibilities
2.3.3 Dual Flame Scanner Operation
Dual flame scanner operation is designed to give extra safety to the flame detection system by adding
a second scanner to verify that the other scanner is working correctly and is detecting the flame
correctly in addition to the self-diagnostics built into the MM.
Option/parameter 122 sets dual flame scanner operation.
Dual flame scanner operation MM Compatibility
IR and UV Mk8 MM, Mini Mk8 MM
IR and Ionisation Mini Mk8 MM
IR or UV Mk8 MM
Ionisation to UV switchover Mini Mk8 MM
Both scanners work independently in detecting a flame signal so it is not required that the two
scanners have to read the same flame signal strength. It is recommended that a good flame signal is
found on both scanners to ensure reliable operation of the dual scanners.
IR and UV, IR and Ionisation
Both flame scanners must detect a flame when there should be and vice versa. If either flame
scanner fails to see a flame when there should be a flame, the MM will lockout on no flame signal,
even if the other scanner detects the flame. This is the same for simulated flame; only one scanner
must see a flame when there should not be, for the MM to lockout.
IR or UV
Either flame scanner must detect a flame when there should be and vice versa. If one flame scanner
fails to see a flame when there should be but the other scanner does detect a flame, then the MM will
continue to fire without a lockout. Only if both flame scanners fail to detect the flame when there
should be and vice versa, will the MM lockout. This is the same for simulated flame; either or both
scanners must see a flame when there should not be, for the MM to lockout.
Ionisation to UV Switchover
The ionisation rod can be used to detect the pilot flame and then the UV scanner can be used to
check the main flame. The pilot type must be set to interrupted pilot or continuous interrupted pilot
(only available on the Mk8 MM) when using ionisation to UV switchover.
AGA
The AGA (Australian Gas Association) requires that there are 2 types of technologies together
checking the flame. Option 122 would need to be set to 3 on the Mk8 MM, and 5 and 6 on the Mk8
MM to comply with this regulation. The UV scanner must be self-check UV scanner to comply with the
AGA regulations.