Signaling Start Preventions; Forced Intermittent Operation; Program Stop Function - Siemens LMV5 Series Basic Documentation

Signaling start
preventions
Forced intermittent
operation

Program stop function

Siemens Building Technologies
HVAC Products
If start is prevented, it is always displayed on the AZL5... .
Start is prevented only when there is demand for heat and one of the start criteria is not
satisfied.
The time from start prevention to display on the AZL5... can be set.
Parameter:
DelayStartPrev
It is also possible to signal start preventions via the alarm output. This function can be
activated and deactivated via
Parameter:
AlarmStartPrev (activated / deactivated)
If «Signaling start preventions» is activated by means of the alarm relay, it is advisable
to pick up power for the reset from the alarm output in order to prevent inadvertent
manual lockouts.
The time from start prevention to signaling at the alarm contact can be set:
Parameter:
AlarmDelay
No matter if the LMV5... is used for continuous operation or intermittent operation (e.g.
when using a flame detector type QRB...), forced intermittent operation can be
activated, this means short automatic shutdown after 23 hours and 50 minutes of
uninterrupted operation.
As a general rule, it is recommended to activate forced intermittent operation or to
leave it activated.
Forced intermittent operation should only be deactivated in plants where this function is
not desired or is unacceptable.
Parameter:
ForcedIntermit (activated / deactivated)
To simplify burner adjustments during commissioning or in connection with
maintenance work, the program sequence of the LMV5... can be stopped at the
following points:
a) Air damper in the prepurge position
b) Traveling to the FGR position
c) Ignition position
d) Interval 1
e) Interval 2
f) Air damper in the postpurge position
g) Traveling to the FGR position
Activation takes place via the relevant menu items on the AZL5... .
Parameter:
ProgramStop (deactivated / 24 PrePurgP / 32 PreP FGR /
36 IgnitPos / 44 Interv 1 / 52 Interv 2 / 72 PostPPos / 76
PostPFGR)
The program stop function is maintained until manual deactivation takes place. If the
system stops at a program stop, a message will appear on the AZL5...
Basic Documentation LMV51...
4 Burner control
Phase
24
32
36
44
52
72
76
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CC1P7550en
01.10.2003