Siemens S120 - Overvoltage Protection

Cabinet design and EMC for components, Blocksize format
10.5 24 V DC Supply Voltage
AC Drive
424 Manual, (GH6), 04/2014, 6SL3097-4AL00-0BP4
Table 10- 1 MCBs by conductor cross-section and temperature
Conductor cross-section
Max. value up to 40° C
Max. value up to 55° C
1.5 mm
2
10 A
6 A
2.5 mm
2
16 A
10 A
4 mm
2
25 A
16 A
6 mm
2
32 A
20 A
The tripping characteristic of the circuit-breaker is selected so that loads remain protected
against the maximum current that occurs in the event of a short circuit of the power supply
unit.
10.5.3
Overvoltage protection
Overvoltage protection devices are needed if long cables are used.
● Supply cables > 10 m
● Signal cables > 30 m
The following Weidmüller overvoltage protectors are recommended for protecting the
components' 24 V power supply and the 24 V signal cables from overvoltage:
Table 10- 2 Recommendations for overvoltage protection
DC power supply
24 V signal cables
Weidmüller
Item no.: PU III R 24V
Order number: 8860360000
Weidmüller
Item no.: MCZ OVP TAZ
Order number: 844915 0000
The overvoltage protectors must always be placed next to the area to be protected, e.g. at
the entry point to the control cabinet.