Siemens LMO39 Series Basic Documentation page 16

Note on parameterization:
Use the AZL2... or ACS410 to always set the exact value of the required time (multiples of increments of 0.147 seconds, 0.294 seconds or 4.851 seconds).
When parameterizing minimum or maximum times, the possibility of a ±7% tolerance must be taken into consideration.
For minimum values: The value to be parameterized must be at least 7% greater. For maximum values: The value to be parameterized must be at least 7% smaller.
Example:
Special case here:
Calculation:
Value to be parameterized (parameter 266): Must be equal to or greater than the calculated value (e.g. 29.106 seconds)
Example:
Calculation:
Value to be parameterized (parameter 267): Must be equal to or smaller than the calculated value (e.g. 4.557 seconds)
Legend TSA Safety time
tw Waiting time
t1 Prepurge time
t3 Preignition time
1) Repetition (maximum number of startups per controlled start)
16/61
Building Technologies
Prepurge time shall be set to 30 seconds
The preignition time is made up of parameter 266 and a time of 5.6 seconds that cannot be parameterized.
30 seconds + 7% - 5.6 seconds = 32,1 seconds - 5.6 seconds = 26.5 seconds
Safety time shall be set to 5 seconds
5 seconds - 7% = 4.65 seconds
t3n Postignition time
t4 Interval between flame ON and release fuel valve 2
t8 Postpurge time
Basic Documentation LMO39...
4 Type summary (other types on request)
CC1P7154en
15.03.2018