Description
THERE ARE SEVERAL TYPES OF CABINETS FOR CRM INSTALLATIONS:
AS – AUTOMATIC STANDARD
Designed for groups of electric receivers with variable reactive power consumption
(group compensation). These installations automatically monitor changes in reactive power consumption using a microprocessor controller with relay outputs and issue commands to connect/ disconnect capacitors to maintain the required power factor.
Switching of capacitors is carried out by electromechanical contactors of a special design with pre-switched current-limiting resistors, thanks to which the starting current is significantly reduced.
US – UNREGULATED STANDARD
Designed for consumers with constant reactive power consumption (individual compensation). Structurally, it differs from the US in the absence of start-up control equipment.
AF – AUTOMATIC WITH FILTER
Designed for groups of electric receivers with variable reactive power consumption at
the harmonic level is THDI > 10% or THD-V > 3%. This level of distortion can harm capacitors.
To prevent this, harmonic filters are connected in series to the circuit, the frequency of which is less than the frequency of the smallest harmonic present in the network. It is possible to use filters
134 Hz (14%) and 189 Hz (7%).
UF – UNREGULATED WITH FILTER
Designed for consumers with constant reactive power consumption (individual compensation) at the harmonic level of THDI > 10% or THD-V > 3%. Structurally, it differs from UF in the absence of start-up control equipment.
TS – THYRISTOR STANDARD
It is a kind of automatic installation.
Designed for groups of electric receivers with sharply variable reactive power consumption.
Switching of capacitors is carried out by thyristor starters, which ensure that the capacitors are switched on without current surges for a short period of time.
This is ensured by the fact that the thyristors open/close at the moment of voltage transition through zero.
TF – THYRISTOR WITH FILTER
Similar to the TS, except that it is capable of operating at a harmonic level of THDI > 10% or THD-V > 3%.