Azbil AUR355, User Manual

Page: 33 / 56

23
Chapter 4. How This Device Operates
„
Sequence chart
The operation sequence of this device is shown below.
z Normal operation
If the start input is turned ON when there is no flame signal, the device transitions
to flame monitoring status (
PF
). If a flame signal is detected while the start input is
ON, the two flame outputs (with and without start check) turn ON. Even if the start
input is turned OFF while the flame signal is detected, both flame outputs continue
to be ON. After that, if the flame signal turns OFF, both flame outputs turn OFF
and the device transitions to controlled shut down status (
--
). In this case, flame
signal turnoff does not trigger recording of playback monitor data.
Start input
Flame signal
Flame output
(with start check)
Flame output
Flame failure
response
Flame relay N.C. output
Input
Display
Output
7-segment display
PF PF PF
Start ON Flame detection Start OFF No flame detected
Operation Operation of this device SHUT
LED
FL
LED
7-seg.
Start input OFF All relays are OFF.
 
- -
Start input ON Flame monitoring starts and relay K3 turns ON.
 
PF
Flame signal input If a flame signal is detected, relays K5, K7 and K8 turn ON.

z
PF
Start input OFF Relays K3, K5, K7, and K8 are ON while the flame signal is detected.

z
PF
Flame signal OFF All relays turn OFF and the device transitions to controlled shut down
status.
 
- -
z : Lit,

: Off,

: Blinks
z Normal operation (when start input ON continues)
When the start input continues to be ON, the two flame outputs (with and without
start check) operate in the same manner as in the case above. The difference from
the normal operation described above (
p. 23
) is that even if the flame signal
turns OFF, the device remains in flame monitoring status (
PF
). In this case, flame
signal turnoff triggers recording of playback monitor data.
Handling Precautions
•
Since the number of playback monitor recordings is limited, if the device is
used in combustion equipment where the flame signal turns off frequently,
the start input should be turned OFF before the burner is stopped.