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Vigi C120 modules Add on residual
current devices for use with C120
MCBs Standard and si type
Protection against
overloads and short
circuits
Technical
Section 9
Dimensions
Section 10
4
Common function
n
The protection of electrical installations against earth faults
n
The protection of persons against indirect contact: medium sensitivities
(300, 500, 1000mA)
n
Supplementary protection of persons against accidental direct contact:
high sensitivity (30mA)
The C120 residual current device complies with BS EN 61009. It is equipped with
a locating device that ensures the correct rating and number of poles.
The technical data of C120 circuit breakers when combined with Vigi modules
remain unchanged and the circuit breakers remain compatible with indication or
control auxiliaries.
Trip sensitivity
n
AC class - Tripped by sinusoidal AC currents whether they are quickly applied
or rise slowly
n
A class - A
k
class: ensures tripping with a DC component current. Tripped by
sinusoidal AC currents as well as by pulsed DC currents whether they are
quickly applied or rise slowly
Trip type
Instantaneous
Provides a trip upon reaching threshold (no intentional time delay).
Selective
s
Provides discrimination with down stream device by introducing an intentional
time delay. Down stream device must be instantaneous with a sensitivity of 1/2 the
upstream device.
si
Provides continuity of supply on circuits with a disturbed supply network. Used
where there is a high risk of nuisance tripping due to:
n
Lightning strikes
n
IT earthing systems
n
Switched electronic ballasts
Desensitised by:
n
Harmonics or high frequencies
n
DC components
Combination of earth leakage modules with circuit
breakers
C120 circuit breaker
Vigi C120 module
+
=
C120 residual current device
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