33 … 68
32 … 68
Printed in Germany • Edition 02.14 • Nr. 254 722
8 Parameters
8.7 P7x - Operation
Parameter
P7x
Designation Description Setting
P73 Modulation degree:
Step width of the
modication
Denes the maximum step width
of a modulation degree modica-
tion without intermediate control.
a) By means of relative modica-
tion via the plus or minus input, the
nominal value is modied upwards
or downwards by the value dened
in P73. Further modications are
accepted as soon as the fan and
the stepped motor work again in
the allowed tolerance range (P25
and P31).
b) Due to new absolute setpoints,
the MPA modies its current modu-
lation degree step by step by the
value dened here until the new
setpoint is reached. After each
intermediate step, the automatic
burner control waits until the fan
and the stepped motor work in the
allowed tolerance range (P25 and
P31).
P74 Modulation degree:
Interval Acceptance
of analogue values
Denes the time interval for the
evaluation and acceptance of the
analogue input in the operating
mode "Modulation degree setpoint
via analogue input" (setting 2 and
3 of P72).
Particularly for the operation with
stepped motor, this time interval
should not be too short in order to
avoid repeated one-step move-
ments forward and backward of the
stepped motor.
See also *1 of P72
P75 Modulation degree:
Lower limit
Denes a lower limit below which
the modulation degree must not
fall. Setpoints which fall below this
limit are adjusted to the allowed
range.
Example: Lower limit = 10 %, new
setpoint = 8 % Automatic burner
control corrects the setpoint to 10 %.
P76 Modulation degree:
Upper limit
Denes an upper limit of the modu-
lation degree which must not be
exceeded. Setpoints which are out-
side this limit are adjusted to the al-
lowed range.
Example: Upper limit = 90 %, new
setpoint = 97 % Automatic burner
control corrects the setpoint to 90 %.