Overall Operation
The digital breaker management relay SIPROTEC 4 7VK61 is equipped with a powerful microprocessor system.
All tasks are processed fully digitally, from the acquisition of measured values up to sending commands to the
circuit breakers. Figure 1-1 shows the basic structure of the 7VK61.
Analog Inputs
The measuring inputs (MI) transform the currents and voltages from the instrument transformers and match
them to the internal signal levels for processing in the device. The device has 4 current inputs and 4 voltage
inputs. Three current inputs are provided for measuring the phase currents, a further measuring input (Ι
4
) can
be configured to detect the earth current (CT starpoint) or a separate earth current transformer. The analog
input quantities are passed on to the input amplifiers (IA).
[hw-struktur-7vk61-oz-251102, 1, en_GB]
Figure 1-1
Hardware-Struktur des Breaker Management Devicees 7VK61
A voltage measuring input is provided for each phase-earth voltage. A further voltage input (U
4
) may be
selected to measure either the displacement voltage, or the additional voltage for synchronism and voltage
check or for any other voltage U
X
(for overvoltage protection). The analogue values are transferred to the IA
input amplifier group.
The input amplifier group IA provides high-resistance termination for the analog input quantities. It consists of
filters that are optimized for measured value processing with regard to bandwidth and processing speed.
The AD analog-to-digital converter group contains analog/digital converters and memory chips for data
transfer to the microcomputer system.
1.1
Introduction
1.1 Overall Operation
18 SIPROTEC 4, 7VK61, Manual
C53000-G1176-C159-5, Edition 05.2018
To Next Page
Loading...
