SAS ST-550 zPID, Руководство пользователя

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ST-550 zPID
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b) Principle of operation (controller with pellet module)
The regulator controls fan and fuel feeder operation in the same way as it is done without pellet module.
Additionally, if pre-programmed, the controller can start CH boiler damping procedure when the pre-set
temperature is reached, and monitor current temperature values. When the temperature drops by a pre-
defined value, the controller may start the fire-up process.
The regulator may also control the grate operation, which helps to maintain the furnace in proper
condition.
c) Stages of controller operation
Parameters of particular operation stages of the CH boiler are configured by the user. Fire-up and damping
are multi-stage processes described below. Once the fire-up process is conducted properly, the controller
enters Operation mode.
• Fire-up
Fire up process is independent of the selected operation algorithm. This stage is activated by the user in
the main menu or by the controller software is certain situations (e.g. when CH boiler temperature
decreases - if automatic fire-up/damping function is active). Fire-up process consists of 3 stages:
1. Initial fuel feeding
In this stage the blow force is limited to the minimum of 1%. The feeder is enabled and remains
active throughout the whole stage.
2. Heater
In the next stage, the heater is enabled and operates until the flue gas temperature increases by
a pre-defined value. The feeder remains inactive in this stage. This phase lasts until the flue gas
temperature increases by 5
o C. If the flue gas temperature does not reach the fire-up temperature
within a pre-defined time from the heater deactivation, another fire-up attempt follows.
After two unsuccessful attempts, the display informs about the fire-up failure. When the fire-up
fails, the controller should be switched off at the power switch and the user should check if there
is any fuel left in the furnace. If so, the furnace should be emptied. If there is no fuel left, the user
should check if there is enough fuel in the fuel tank. Then, the controller should be switched on
again and the fire-up process should be activated anew.
3. Delay
Delay is the last stage of the fire-up process and it involves stabilizing the controller parameters.
Throughout this stage the feeder operates according to
operation time and pause time settings and
the fan operates at a pre-defined speed.
NOTE :
The furnace needs to be cleared before each fire-up attempt.
•
Operation
Once the fire-up process is completed, the controller enters operation mode and the display shows the
following message: ‘
PID:OPERATION’ . It is the primary mode of controller operation in which the fan
operation and fuel feeding is automatically controlled with PID algorithm, oscillating around the preset
temperature. If the temperature rises unexpectedly by more than 5
o C above the pre-set value, the so
called supervision mode is activated or the CH boiler is damped.
•
Supervision mode
This mode is activated automatically if the temperature exceeds the pre-set value by 5 o C when in
operation mode. In such a case, the controller disables PID control and uses manual settings (according
to parameters defined in the fitter's menu) in order to reduce the temperature of the circulating water (
the display shows the following message:
‘PID:SUPERVISION’ ), initiates the damping process (if such
an option is selected in the fitter’s menu).