PFCL Elite 6 / PFCL Elite 12
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1.2.3 Stages
and
Steps
We must explain the difference between stages and steps. In this manual, a STAGE is described as the
capacitor banks in which the power factor compensation unit is divided, which may have different power
ratings, usually in 1:1, 1:2, 1:2:4, etc. ratios.
A step is each one of the total power fractions (power of the first step) that can be regulated with the use of
stages with a different weight.
1.2.4 Regulation
Program.
The power ratings of the different groups or stages usually follow certain patterns called "programs”. The
program indicates the power ratios between different stages. The most frequent programs are:
Program 1:1:1:1.
All stages have the same power. For example, a 100 kvar unit with 5 steps would be
composed of 5 identical 20 kvar stages and it would be described as a (5 x 20) kvar unit.
Program 1:2:2:2
. All stages after the second stage have twice as much power as the first stage. For
example, a 180 kvar unit with 5 stages would be composed of a first 20 kvar stage and 4 identical 40 kvar
stages. It could be described as a (20 + 4 x 40) kvar unit.
Program 1:2:4:4.
The power of the second stage is twice as much as the first stage and all other stages
after the third stage would have four times as much power as the first stage. For example, a 300 kvar unit
with 5 stages would be composed of a first 20 kvar stage, a second 40 kvar stage and 3 identical 80 kvar
stages. It could be described as a (20 + 40 + 3 x 80) kvar unit.
Other Programs
. Other programs can be used, such as 1:2:2:4, 1:2:4:8 or 1:1:2:2, etc. The meaning of the
numbers, as assumed in previous cases, shows the proportion of the powers between the first stage, which
receives a value of 1 and the next stages (2 means twice as much power, 4 means four times as much
power, etc.).
The unit can easily configure one of the 10 standard programs, which are as follows:
1:1:1:1, 1:2:2:2, 1:2:4:4, 1:2:4:8, 1:1:2:2, 1:1:2:4, 1:2:2:4, 1:2:3:3, 1:2:3:4, 1:2:3:6.
An open program can also be configured between 1:1:1:1 and 1:9:9:9 in special cases.
1.2.5 Plug
and
Play.
A series of parameters must be configured when a power factor regulator is installed, to make sure that it
operates correctly. Some of these parameters might be hard to know, such as, for example, the voltage
phases or the voltage corresponding to the current measured, as well as the current transformer ratio. PFCL
Elite has been designed with a smart automatic process that detects the necessary parameters, such as:
¾
C/K: calculates the ratio of the current transformer and the power of the smallest step.
¾
Phase: Identifies the voltage sequence and correspondence with current. In other words, it identifies
the
U
L1
,
U
L2
,
U
L3
, when the current measured is
I
L1
,
I
L2
,
I
L3
and whether it is connected in the
opposite way or not.
¾
Number of stages installed and Program: the system connects all stages in a sequence, finds out
how many stages are installed and then calculates the program, i.e., the power ratio of the
capacitors (see Section 1.2.4).
1.2.6 Connection and Reconnection Time.
Connection time Tc defines the minimum time between changes in the status of stages, i.e., between
connections and disconnections. Therefore, the configuration of this parameter has a direct impact on the
compensation speed, in other words, on the monitoring capacity after changes in load. Establish a shorter
connection time to improve the power factor correction when the load can change quickly.
However, a shorter Tc will lead to a higher number of connections per time unit, shortening the useful life of
the associated components (contacts, capacitors). To assess the number of connections, PFCL Elite uses
individual meters for each capacitor.
The reconnection time is the minimum time between the disconnection of a stage and its reconnection. This
time is required to discharge the capacitor enough to prevent an over-current in the system after it is
reconnected.
