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intelligent ELCB

Earth leakage circuit Interrupter:

The earth leakage circuit breaker the circuit , If the current edžceeds
called Ground Fault Circuit Interrup- its speciĮed values (delta I) , the
ter and its construcƟon GFCI and signal is sent to circuit breaker to
called too Residual Current Device disconnect the circuit to protect the
and its construcƟon RCD͘ human ͘
The earth Leakage CB device used in
human protecƟon form the electric

shock when touch the bodLJ of the
machine͘
The idea of working:
Most of earth leakage circuit break-
ers depends on founding diīeren-
Ɵal relaLJ which sense anLJ changing
in current value which passing in

To choose the earth leakage circuit breaker must select three values:

I: its current values which if the current increased about Founding more
this value disconnect the circuit. of delta I value:
ISC: ŝƚ͛Ɛ ŽƉƟŵƵŵ ƐŚŽƌƚ ĐŝƌĐƵŝƚ ĐƵƌƌĞŶƚ ǀĂůƵĞ ǁŚŝĐŚ ďĞĂƌ
it the cb without damage This value is increased as we 10 mA: used in swimming pool to pro-
approach the transformer, depending on the value of tect human from any electric leakage to
ƚŚĞ ^ ƌĞƐŝƐƚĂŶĐĞ͘ the swimming pool.
Delta I salue: ŝƚ͛Ɛ ĐŚĂŶŐŝŶŐ ĐƵƌƌĞŶƚ ǀĂůƵĞ ǁŚŝĐŚ ƚŚĞ ϯ0 mA: in the houses, shops, etc.
circuit breaker disconnected in it to protect the human 100 mA, ϯ00 mA: used in the factors
from electric shock.
which the current high.

The tLJpes of the

earth leakage circuit

breakers:

Combined: any circuit breaker con-
sist of earth leakage detector and use
directly
Separated tLJpe: the circuit breaker
ŚĞƌĞ ĚŽĞƐŶ͛ƚ ĐŽŶƐŝƐƚ ŽĨ ĞĂƌƚŚ ůĞĂŬĂŐĞ
detector and added to it device called
residual current device to work as earth
leakage circuit breaker.

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