Schweitzer Engineering Laboratories SEL-734W, Справочник по полевым условиям эксплуатации

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Date Code 20191029 Field Reference Guide SEL-734W and SEL Wireless Current Sensor
SEL-734W and SEL Wireless Current Sensor Instruction Manual
S E C T I O N 6
Differences Between the
SEL-734B and the SEL-734W
Overview
The SEL-734B receives an analog representation of the current in the power line
being monitored. The analog signal is digitized in the SEL-734B. The digitiza-
tion rate of the SEL-734B is fast enough that the system runs as if it is continu-
ously varying data. The SEL-WCS samples the representation of the power line
current at a high rate, but only for the few cycles it requires to determine the state
of the current (amplitude and spectral content). The SEL-734W receives the
information and repeatedly uses it until a new update is received. The SEL-734W
supports all the same functions of the SEL-734B, such as metering, power quality
and event analysis, waveform capture, Sequence of Events (SOE) reporting, and
capacitor bank control operation. The degree to which each of these functions is
impacted is determined by how often the function updates relative to the update
rate from the SEL-WCS and how much the current changes between sensor
updates. Each of these functions is described in this section.
Capacitor Bank Control Strategies
The SEL-734B provides different capacitor bank control strategies and switching
options depending on its hardware options. See the
SEL-734B Field Application
Guide and Template Guides for details. The template guides specify the list of
control strategies that are available for each hardware option. Table 6.1 compares
the control strategies between the SEL-734B and SEL-734W.
Table 6.1 SEL-734W and SEL-734B Control Strategy Comparison
Control Strategies Compact Enclosure
Full-size
Enclosure
SEL-734W SEL-734B
4-Jaw 4-Jaw 6-Jaw Option A 6-Jaw Option B 7-Pin
Voltage Control Yes Yes Yes Yes Yes Yes
kVAR Control Yes No Yes Yes Yes Yes
Power Factor Control Yes No Yes Yes Yes No
Current Control Yes No Yes Yes Yes No
Time-Based Control Yes Yes Yes Yes Yes No
Ganged Phase Control Yes Yes Yes Yes Yes Yes
Individual Phase Control No No No No No Yes