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Introduction
1.1 Overall Operation
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008
21
The 4 voltage transformers of the 7SJ623, 7SJ624 and 7SJ64 can either be applied for the input of 3 phase-
to-ground voltages, one displacement voltage V
delta
or a further voltage for the synchronizing function.
The analog input quantities are passed on to the input amplifiers (IA). The input amplifier IA element provides
a high-resistance termination for the input quantities. It consists of filters that are optimized for measured-value
processing with regard to bandwidth and processing speed.
The analog-to-digital (AD) element consists of a multiplexor, an analog-to-digital (A/D) converter and of memory
components for the transmission of digital signals to the microcomputer system.
Figure 1-2
Hardware structure of the numerical multi-functional protection devices
7SJ623, 7SJ624 and 7SJ64
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