Beretta 20141085, Installation Manual

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4.5.2 Par 148 = 1
In this mode the system manages the cascade so that the minimum
number of modules is on.
The first difference in relation to mode 0 refers to the logic with which
the modulation of Depending modules within the cascade is man-
aged.
In fact, while each thermal module modulates with its own PID in
mode 0, no more than two Depending modules modulate with the
same criteria in mode 1, while the remaining modules operate at max-
imum power. The diagram is represented in the following figure:
Managing
Managing
PID
PID
100%
100% 100%
100% 100% 100%
PID
PID PID
PID PID
PID PID
Managing
Managing
Managing
Practically speaking, if more than two thermal modules are on, only
two thermal modules are controlled via PID, while the others receive a
signal to move to maximum power.
The second difference refers to the start-up/shutdown rules of the in-
dividual modules.
In any case, the start-up and shutdown rules are managed according
to the indications shown in the previous graph. The difference is that it
is also possible to have start-ups/shutdowns of the Depending mod-
ules in the "balancing" zone.
This additional start-up criteria (valid in the balancing band only) en-
sures that a module is started-up when any one of the two modules
controlled by a PID adjustment has reached a threshold power (Par
82) once a specific wait time defined by Par 75 has elapsed.
Similarly (still within the balancing band), a module is shutdown if both
modules controlled by a PID adjustment have reached a percentage
of power which is below the minimum power threshold (Par 83) once
a specific wait time defined by Par 75 has elapsed.
4.5.3 Par 148 = 2
In this mode the system manages the cascade so that the maximum
number of modules is on.
This mode is similar to mode 0 apart from the start-up and shutdown
rules.
In this case the rules based on the information illustrated by the pre-
vious graph are still valid, with the following differences (in any case,
always applicable to the "balancing" band only):
To add an additional depending module, the managing module eval-
uates whether the sum of the power (calculated on the basis of the fan
speed) of all the active thermal modules is greater than the product
between the number of the active depending modules increased by
one and the minimum power value (Par 152) increased by a hyster-
esis value (defined by Par 153). [ Σ ( P1,P2,…Pn) > (n+1) * (Par 152)
+ (Par 153)].
To shutdown a depending access, the managing module evaluates
whether the sum of the power (calculated on the basis of the fan
speed) of all the active thermal modules is less than the product be-
tween the number of the active depending modules and the minimum
power value (Par 152). [
Σ
( P1,P2,…Pn) < (n) * (Par 152)].
b
We must consider that the percentage of power varies from a
minimum of 1% and a maximum of 100% and therefore, the
parameter values 152 and 153 are not to be taken as the per-
centage of absolute power.