GE Multilin DFF, Instruction Manual, Page: 32 / 74

HARDWARE DESCRIPTION
GEK-106166E DFF Digital Feeder Relay 31
6.1.4 IDENTIFICATION.
The identification label of the model is located at the right of the keypad. This label includes the model number, serial
number and the most important nominal values.
Terminal blocks placed at the rear plate are identified by black lettering. Each of the terminals blocks are identified by
a letter printed at the top, close to the connector. The code uses letters of the alphabet beginning with A at the right
hand edge of the case when viewed from the rear.
The 12 terminals of each block are identified by a number between 1 and 12 that is printed on the rear plate close to
each connector The numbers run from 1 at the top to 12 at the bottom. The IRIG-B terminals are identified by the “+”
and “-“ sign.
For relays with fiber optics communications (plastic or crystal), transmission and reception connectors terminals are
identified by TX and RX respectively.
6.1.5 MAGNETIC MODULE.
The magnetic module connects the substation voltage signals to the relay providing galvanic isolation by means of
internal transformers and reduces the voltage levels for the internal circuitry.
As the magnetic module connects to HV equipment it must be capable of withstanding electromagnetic disturbances.
To avoid this effect, the relay has filters in the primary side of the transformer and in the secondary side.
6.1.6 PROTECTION CPU MODULE
This module performs the following functions:
•
Samples the analog signals from the magnetic module.
•
Evaluates protection algorithms.
•
Performs protection and auxiliary functions.
•
Carries out monitoring functions, events logs, oscillography, etc.
•
Equipment auto-diagnostic.
•
Sends protection data to the communications CPU.