KMB NOVAR-1 Series, Руководство по эксплуатации

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Novar 1xxx KMB systems
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5.4.4 Communication
Despite of standard models, the Novar-1312 controller doesn’t support the Modbus-RTU protocol.
5.5 Operation
5.5.1 Thyristor and Contactor Group
The controller features twelve transistor outputs, T1 through T12, and two relay outputs, R13 and R14.
Thyristor switches can be connected directly to the transistor outputs. Contactors can be connected
directly to the relay outputs. Thyristor switches must be connected successively starting with output T1
while the number of outputs used must be specified in parameter 28 on controller powerup (the
parameter’s default value is 0).
Display test will take place first on powerup. Information as described in Chapter 3.1 will then be
displayed momentarily while the last parameter displayed is the number of transistor outputs used
(such as
t=O t=O t=O t=O
).
After that you have to set the parameter to the actual number of thyristor switches connected to the
transistor outputs. The automatic connection configuration detection process and automatic section
power recognition process follow in a standard way as described in Chapters 3.2 and 3.3.
Parameter 28 value defines the thyristor group , which is a group of outputs to which thyristor
switches are connected. All the other outputs are the contactor group . Example: parameter 28 is set
to 3 – outputs 1 through 3 are the thyristor group and outputs 4 and 14 are the contactor group.
The thyristor groups outputs are used by the controller for fast control process. The contactor group
outputs are used for slow control process (see further below).
If not all the transistor outputs are used for connection of thyristor switches, the unused ones can be
used for connection of contactors; contactors, however, must be connected to the transistor outputs
via auxiliary relays (such as Schrack RT with 24 V DC coil). A wiring example is shown in an
appendix.
5.5.2 Control Principles
Two simultaneous, into a degree independent, control processes take place in Novar1312 controller:
•
fast control process with thyristor group outputs driving semiconductor switches
•
slow control process with contactor group outputs switching contactors
Fast control process has a measurement stage, calculation stage and execution of control
intervention. The control intervention rate, as well as the transistor outputs’ reconnection delay time,
can be specified to allow control process adaptation to power of the quick-discharge resistor used.
The sections that only differ by less than a quarter from the transistor group’s smallest section are
considered equal by the controller and they are switched cyclically. When calculating the optimum
control intervention, only each control section’s value is important (number of connections is not
evaluated.
Slow control process has to respect limitations from the compensation sections’ contactors’
parameters and service life. Phase measurement takes place once a second and control phase
timing, which can only repeat every five seconds, is determined by the control deviation evaluated and
control period specified. When calculating control intervention, the reconnection delay time has to be
respected too. The optimum control intervention is chosen not only on basis of the sections’ values,
but also from the point of view of the number of switching operations on each section, the time since
the last disconnection and the total number of switching operations within a control intervention.