Program Sequence Of Burner Control (Function); Program Selection; Forced Intermittent Operation; Burner Control Program - Siemens LMS14 User Manual

6.35 Program sequence of burner control
(function)

6.35.1 Program selection

Certain sections of the burner control's program can be changed via parameters,
thereby providing a choice of control sequences. The burner control's program
sequences are distinguished mainly by their capacity ranges within which the boiler
shall operate.
In accordance with the standards, 2 capacity ranges are in use:
 <120 kW
 ≥120 kW
For both capacity ranges, a number of parameter setting choices are available,
enabling the OEM to match the burner control's control sequence and time
characteristics to individual needs.

6.35.2 Forced intermittent operation

Forced intermittent operation ensures that the burner control shuts down after a
maximum of 24 hours of continuous operation. This is to make certain the burner
control performs the required startup and shutdown sequences.

6.35.3 Burner control program

The burner control program ensures orderly operation of the unit including startup,
shutdown, and flame supervision. The sequence itself can be changed by setting a
number of parameters. If there are deviations from the required control sequence, or
after a reset, the program will respond by triggering safety lockout (home run) followed
by lockout, restart or start prevention, depending on the settings made. Sequence
control is phase-oriented. The individual phases of the program are summarized to
groups, such as startup, operation, shutdown and home run. After a reset (power ON),
the burner control starts its home run. Depending on the available (parameterized)
input/output signals or program times (e.g. prepurging), the individual phases of the
program are executed or skipped. The burner control's program is designed for
intermittent operation. To confirm correct functioning (detection of faults); a complete
operating cycle is required. In the Standby position, the burner control is ready to
operate and waits for a request for heat from the controller, or it prevents burner startup
(release missing). The burner control maintains the operation position until requests for
heat from the controller are no longer present, but for no more than 24 hours. After this
period of time, the burner control will automatically trigger forced intermittent operation.
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Building Technologies Division User Manual LMS14... CC1U7471en
6 The settings in detail 28.01.2015