Tech Controllers ST-979, Руководство пользователя

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TECH
4
III.
Controller installation
The controller should be installed by a qualified person.
WARNING
Risk of fatal electric shock from touching live connections. Before working on the
controller switch off the power supply and prevent it from being accidentally switched
on.
IV.
How to use the controller
IV.a) Principle of operation - Lambda sensor
Additionally, the controller operation depends on LAMBDA sensor readings which provide the
information about the proportion of oxygen in the flue gas. On the basis of this value, the efficiency
of the burning process is assessed. If the amount of oxygen is different from the pre-set value,
the regulator adjusts the fan speed as well as the amount of fuel fed to the boiler in order to make
the process more efficient.
IV.b) Operation stages:
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 or Modulation mode - it depends on the operation
algorithm selected by the user in Fitter’s menu / Operation algorithm select.
Fire-up
Fire-up process does not depend on the current operation algorithm. This phase is initialized by
the user in the main menu, or by the controller software in certain situations (e.g. after periodical
cleaning of the furnace during controller operation). There are four stages of the fire-up process:
1. Blow-by
In this stage the fan works at full speed in order to clean the furnace.
2. Initial fuel feeding
In this stage the blow force decreases to its minimum value - 1%. The feeder is enabled and
operates throughout the whole stage. Feeding time is set by the user in the main menu – Fitter’s
menu / Fire-up parameters.
3. Heater
In the following stage of the fire-up process the igniter is enabled. It remains active until the flue
gas temperature increases by a pre-set value. The feeder is inactive whereas the fan operates at
the speed defined by the user – Fitter’s menu / Fire-up parameters.
4. Delay
Delay is the final stage of the fire-up process, when the controller parameters stabilize. In this
stage the feeder operates according to operation time and pause time settings. The fan operates
at the speed defined by the user – Fitter’s menu / Fire-up parameters. Duration of this stage is
also defined by the user.
Standard operation algorithm:
1. Operation
The main aim of this stage is reaching the pre-set CH boiler temperature. Fan and feeder operation
is regulated according to user’s settings - Main menu / Operation settings. Once the pre-set
temperature is reached, the controller switches to sustain mode.
2. Sustain
Fuel feeding process slows down in order to smoothly reduce the temperature. The fan and the
feeder operate according to customized settings - Main menu / Operation settings.