Lamtec F300K Series, Manual

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64
7 Operation
Switch-on time
By means of the switch-on time, short-term flame pulse rates that would result at startup of
the burner in a report of extraneous light in connection with the pre-ventilation of the burner
and/or background fire can be suppressed for the set time.
The maximum switch-on time that can be set depends on the first safety time of the burner
(e.g. 2 seconds for gas burners and 3 seconds for oil burners). If the pilot burner is being mon-
itored at the same time, its operating hours are applicable. Note that the F300K also requires
1 second for switch-on. When everything is taken into account, you have to deduct this from
the first safety time.
Ultimately, the actual signal of the flame to be monitored must remain stable for as long as the
set switch-on time to allow a "flame ON" through connection.
Level of suppression
The level of suppression is effective in connection with the switch-on time. In the burner's start-
up phase, in the event of recurring pulse rates of extraneous light signals, these are more or
less additionally suppressed. After each interruption of the pulse rates, the elapsed switch-on
time is reset within a time span of 0.3 to 5 seconds.
The level of suppression applies inversely. The shorter the time, the longer it has an effect on
the switch-on time behaviour.
If a setting is necessary here, you should only make adjustments by small increments. If the
time is too short, it could prevent the burner from starting at all.
NOTICE
Use of automatic optimisation again
Once you have further optimised the startup suppression P 24 and P 25 and transferred it to
the flame scanner,you can take the "Analyse" step in image 340 (see the menu tree in section
5.2 Menu tree ) to carry out further automatic optimisation of the trigger threshold for this set-
ting. The already learned "flame ON" and "flame OFF" data is used for this.
24: Switch-on time 0.2 ... 5.0 sec. Switch-on time of the flame relays after
the appearance of the "flame ON" signal
25: Level of
suppression 0.3 ... 5.0 sec. Level of suppression of parts of the signal
that do not belong to the signal of the
intended flame (suppression of extrane-
ous light)
Icon Name Value Explanation