VAMP Ltd
Arc protection system
User manual
VAMP 220 / 220R
VM220.EN004
Vamp 24h support phone : +358 (0)40 573 6316
15
Up to four trip functions are available by connecting TRIP1
and/or TRIP2 output to the control inputs of the trip multiplier
relay. Auxiliary supply voltage is available from the 24 V OUT
terminals of the master unit.
2.6.
Systems with multiple master units
Especially in medium-voltage switchgears the power may be
fed from two or more infeeders. At an arc fault situation, each
infeeder that can supply short circuit power must be tripped. In
these applications, the arc protection system may include
several master units, that is, one master unit per infeeder.
In applications with multiple master units, the master units
are interconnected via the BI/O connectors. When an arc sensor
in the system is activated, information is transferred over the
BI/O lines to all master units in the system. As a consequense,
all master units with the overcurrent subunit activated will
trip their respective circuit breakers.
If a master unit connected to the BI/O lines is tripping, and the
arc or overcurrent activation comes from a BI/O connection, the
identifier of the activated BI/O line will be shown on the
display.
2.7.
Selective arc protection
The master unit facilitates a selective arc protection even in
more complex electricity distribution systems. As mentioned
earlier, it includes the following input/output modules:
•
unidirectional arc input
•
unidirectional arc output (current dependent)
•
bidirectional arc in/output
•
unidirectional overcurrent output
•
bidirectional overcurrent in/output.
By utilizing these features, complex busbar systems can be
divided into separate zones. Each zone includes the parts of the
distribution system that are limited by two or more circuit-
breakers. See the example in Figure 2.7-1. Selective arc
protection means that all zones are protected independently of
each other.
In the example in Figure 2.7-1, VAMP 220 master units are
used for tripping the circuit-breakers K4, K5, K6 and K7 as
well as the actual infeeding circuit-breakers K1, K2 and K3.