NOTICE
Suitable fuse for the power supply cables (corresponds to "Limited Energy")
The current on the terminal may not exceed 3 A. Use a fuse for the power supply that is suitable
for protection of AC/DC power supply circuits *
)
and protects against currents > 3A.
• In areas subject to the NEC or CEC, the fuse must meet the following requirements:
– Suitable for AC/DC *
)
(min. 60V / 3A)
– Breaking current at least 10 kA
– Approval according to ANSI/UL 248-14 (suppl. fuses), ANSI/UL 248-4 (Class CC), ANSI/UL
248-8 (J), ANSI/UL 248-15 (T), or CSA C22.2-4 No. 248.14 (suppl. fuses), No. 248-4
(Class CC), No. 248-8 (J), No. 248-15 (T)
• In other areas, the fuse must meet the following requirements:
– Suitable for AC/DC *
)
(min. 60V / 3A)
– Breaking current at least 10 kA
– Approval according to IEC/EN 60947‑1/2/3 or IEC/EN 60898-1/2 for circuit breakers
– Switch o characteristics: B or C
– Approval according to IEC/EN60127-1 for fuses
– Switch o characteristics: max. 120 s at 2 x I
n
(corresponds to melting integral I
2
t < 4320)
If the properties of the supplying current source are known, the following fuse is also possible:
• In areas subject to the NEC or CEC, the fuse must meet the following requirements:
– Suitable for AC/DC *
)
(min. 60V / 3A)
– Breaking current > highest possible current of the current source (incl. short circuit
current and fault)
– Approval according to UL 1077 or CSA C22.2 No. 235
• In other areas, the fuse must meet the following requirements:
– Suitable for AC/DC *
)
(min. 60V / 3A)
– Breaking current > highest possible current of the current source (incl. short circuit
current and fault)
– Approval according to IEC/EN 60934
– Switch o characteristics: max. 120s at 2 x I
n
You do not need to fuse the supply cable if you only use power sources with a limited power
source (LPS) or power sources according to NEC Class 2 or PS2/LPS according to UL 62368-1 for
the power supply of the devices.
*
)
AC or DC depending on availability
Connecting up
6.324VAC/DC power supply
SCALANCE XR-300
Operating Instructions, 03/2023, C79000-G8976-C586-02 61