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Dimensions
Section 12
Influence of ambient
temperature
Technical advice
Influence of temperature on the operation
Devices
Characteristics
influenced by
temperature
Temperature
Min.
Max.
iDPN, C60H-DC, C60, C120, NG125,
C60PV-DC circuit breakers
Tripping on overload
-30°C +70°C
Tripping on overload
-25°C +60°C
iC60N circuit breakers
Tripping on overload
-35°C +70°C
Circuit breakers
With Vigi (AC)
Tripping on overload
-5°C +60°C
With Vigi (A,
SI
)
-25°C +60°C
Reflex iC60
Tripping on overload
-25°C +60°C
iC60H RCBO,
Tripping on overload
-15°C +60°C
C60NA-DC, SW60PV-DC switch-
disconnectors
Maximum operating current
-25°C +70°C
Maximum operating current
-5°C +60°C
iID residual current
circuit breakers
AC
Maximum operating current
-5°C +60°C
A,
SI
-25°C +60°C
Switches
iSW
Maximum operating current
-20°C +50°C
iSW-NA
-35°C +70°C
Protection auxiliaries
None
-35°C +70°C
RCA, ARA control auxiliaries
None
-25°C +60°C
iCT contactors
Installation conditions
-5°C +60°C
iTL impulse relays
None
-20°C +50°C
iCT, iTL auxiliaries
None
-20°C +50°C
Distribloc
Maximum operating current
-25°C +60°C
Multiclip
Maximum operating current
-25°C +60°C
Note: the temperature considered is the temperature viewed through the device.
Circuit breakers
High temperatures
b
b
A rise in temperature causes lowering of the thermal threshold
(tripping on overload).
b
b
Protection is still ensured: the tripping threshold remains lower than the current
acceptable by the cable (I
z
)
b
b
To prevent nuisance tripping, it should be checked that this threshold remains
higher than the maximum operating current (I
B
) of the circuit, defined by:
v
v
the rated load currents,
v
v
the coefficients of expansion and simultaneity of use.
If the temperature is sufficiently high for the tripping threshold to become lower than
the operating current I
B
, switchboard ventilation should be provided for.
Low temperatures
b
b
A fall in temperature increases the thermal tripping threshold of the circuit breaker.
b
b
There is no risk of nuisance tripping: the threshold remains higher than the
maximum operating current of the circuit (I
B
) demanded by the loads.
b
b
It should be checked that the cable remains suitably protected, i.e. that its
acceptable current (I
z
) is higher than the values shown in the following tables
(in amperes).
When the ambient temperature could vary within a broad range, both these aspects
must be taken into account:
b
b
the difference between the maximum operating current of the circuit (I
B
) and the
tripping threshold of the circuit breaker for the minimum ambient temperature,
b
b
the difference between the strength of the cable (I
Z
) and the maximum tripping
threshold of the circuit breaker for the maximum ambient temperature.