Features Of Each Control; Cyclic Control Operation - Mitsubishi Electric VAR-6A User Manual

4. Explanation of Control and Movement
4.4 Features of each Control
The features of each control is shown below.
Control name
Cyclic control The cyclic control is suitable for controlling capacitors with equivalent capacity. Since
the number of the switching operation of the vacuum electromagnetic contactors are
made equally, long lifetime can be expected. It is necessary to replace all the contactors
at the same time.
Priority control The priority control is suitable for controlling the different - capacity capacitor group in
stable load circuit which use the large - capacity capacitor on base and adjusts changes
of reactive power on the small - capacity capacitors. But since the switching of certain
vacuum electromagnetic contactors will become more frequent than those of others,
maintenance and inspections must be made frequently and each contactor must be
replaced at the end of their respective lifetime.
Optimal control The optimal control is suitable for controlling the different - capacity capacitor groups
in the circuit where load fluctuation is frequent. But since the switching of vacuum
electromagnetic contactors become frequent and not equal, the maintenance and
inspections must be performed frequently and each contactor must be replaced at the
end of their respective lifetime.
4.5 Cyclic Control Operation
■ In the cyclic control, the number of the
switching operation of each capacitor
circuit are made equally.
■ At the time of turning on the power
supply, the connection begins with C1
and proceeds as follows:
C1→C2→C3→C4→C5→C6
It operates as follows in the case of 12
circuits.
C1→C2→.........→C11→C12
■ The disconnection also begins with C1
at the time of turning on the power
supply and proceeds in the same
manner as the connection:
C1→C2→C3→C4→C5→C6
It operates as follows at the time of 12 circuits.
C1→C2→.........→C11→C12
■ The cyclic control is suitable for controlling capacitors with equivalent capacity. Since the
switching operation of the vacuum electromagnetic contactors are made equally, long lifetime
can be expected. It is necessary to replace all the contactors at the same time.
■ When Combination ON/OFF set-up is ON , a control method serves as only cyclic control.
Feature
Cyclic Control Opration
increase
Load Change
the number of
connection banks
16
decrease increase increase
decrease
decrease