22
LYNX 3400
manual
72789_b
/
NX2009363
4.1. Function by function description
The LYNX 3400 Detector is a fault detector for underground MV network of 15kV or
20kV voltage based on the Directional principle ie a simultaneous monitoring of
residual current and voltage.
It is in the form of a mono-card mounted in a housing designed to work inside a
station
The current signals are derived from 3 Tore type ITI sensors with a ratio of 500/1.
The voltage signals are derived from voltage sensors to be installed on the separable
connectors.
The detector permit possible to locate the faulty section of a departure object that is
permanently defective by means of illuminated signals.
In addition, it records all fault occurrences (self-extinguishing, fugitive, semi-
permanent and permanent) in a counter (viewable by a display) and activates the
external contact (s) corresponding in the to help locate the works to be maintained
Depending on the place of installation, there are two types of detectors differentiated
by their energy workshop:
- Autonomous sensors powered by interchangeable batteries
- Detectors with an LV battery (230v Ph + N) backed up by an interchangeable
battery or by a supercapacitor device without replacement elements
The interface with external equipment is realized by three contacts pulled out on
removable and undecided screw terminals
Identification of the type of defects
Single phase phase-to-earth fault:
The detection of this fault is only possible if high voltage has been present for more
than 5s. Each directional sensor on the faulty start flashes a constant color: Either red
or green.
In addition, depending on the equipment of the LYNX 3400:
- The red counter or the green counter is incremented by one.
- The red contact or the green remote control contact closes
polyphase faults
These faults are identified by a green / red flash every second.
Only directional detectors upstream of the fault will flash and both red and green
output contacts will close simultaneously