VAMP Ltd
Arc protection system
User manual
VAMP 220 / 220R
VM220.EN004
Vamp 24h support phone : +358 (0)40 573 6316
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Figure 2.3-1 Arc sensor VA 1 DA.
A sudden increase of the light intensity is interpreted as an arc
fault. The electronic circuits of the sensor transforms the light
message into a current message and transmits it to the slave
unit, which forwards it to the master unit.
The sensitivity of the sensor is nearly equal over the front side.
At the rear side the sensitivity decreases remarkably. See
Figure 2.3-2. In a switchgear, however, the light caused by an
arc is reflected from the walls. Therefore, the mounting position
of the sensor is not critical.
The standard sensor cable length is 6 m. As an option, a
shielded cable can be used for distances up to 20 m.
40 30 20 10 0
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100%
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Figure 2.3-2 The sensitivity of the arc sensor to light from different
directions.
2.4.
Portable sensor VA 1 DP
This module is a portable sensor element which can be
temporarily connected to the slave units. It is used to improve
personal safety during work, for instance during maintenance
work, in a live switchgear. The sensor should be located close to
the place where work is done. It can, for instance, be attached
to the breast pocket of the service man's shirt or boiler suit.
The function of the portable arc sensor equals that of the fix-
mounted arc sensors. The difference is that the portable arc
sensor can be moved around within the reach of the connection
cable.