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Building Technologies
Basic Documentation LMV27...
CC1P7541en
7 Basic unit LMV27
17.12.2018
7.2 Flame detectors
For display of the flame on the AZL2, the following general conditions apply:
Display is subject to various component tolerances, which means that
deviations of
10% can occur
Note that, for physical reasons, there is no linear relationship between flame
display and detector signal values
The LMV27 can be used with different types of flame detectors. For the correct use of
flame detectors, refer to the chapter
Sequence diagrams
.
The flame detector used must be correctly parameterized.
In the hardware of the LMV27, the flame signals are subdivided into 2 groups (group 0
covering the QRB and QRC, and group 1 covering ionization and the QRA). The flame
detector for gas is selected via parameter 221, that for oil via parameter 261.
No. Parameter
221
Gas: Active detector flame evaluation
0 = QRB / QRC
1 = ION / QRA
261
Oil: Active detector flame evaluation
0 = QRB / QRC
1 = ION / QRA
7.2.1 Loss of flame
In the event of loss of flame, the unit initiates safety shutdown, followed by a restart, if
required. A repetition counter can be used to select the number of flame losses after
which the unit shall initiate lockout (refer to chapter
Repetition counter
).
Error
code
Diagnostic
code
Meaning for the LMV27
7
0
Loss of flame
No. Parameter
186
Software drop out delay time of flame signal (100 ms)
Index 0 = QRB / QRC (0 = deactivated, >1 = activated)
Index 1 = ION / QRA (0 = deactivated, >3 = activated) (only 200 ms-steps)
194
Repetition limit no flame at the end of safety time (TSA)
1 = no repetition
2...4 = 1...3 repetitions
Recharging time:
Entering into operation
240
280
Repetition limit value loss of flame
1 = no repetition
2 = 1 repetition
Recharging time:
After the
Operation
phase
Caution!
The response time of the flame detector leads to an extension of the second
safety time! This must be taken into consideration when designing the burner!