Siemens S7-1200 System Manual page 75

Table 3- 17 AC suppressor circuit resistor and capacitor values
Inductive load
I rms
Amps
0.02
0.05
0.1
0.2
0.05
1
2
Conditions satisfied by the table values:
Maximum turn-off transition step < 500 V
Resistor peak voltage < 500 V
Capacitor peak voltage < 1250 V
Suppressor current < 8% of load current (50 Hz)
Suppressor current < 11% of load current (60 Hz)
Capacitor dV/dt < 2 V/μs
Capacitor pulse dissipation : ∫(dv/dt)
Resonant frequency < 300 Hz
Resistor power for 2 Hz max switching frequency
Power factor of 0.3 assumed for typical inductive load
Guidelines for differential inputs and outputs
Differential inputs and outputs behave differently than standard inputs and outputs. There
are two pins per differential input and output. Determining whether a differential input or
output is on or off requires that you measure the voltage difference between these two pins.
See the detailed specifications for the CPU 1217C in Appendix A (Page 879).
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG
230 VAC 120 VAC
VA VA
4.6 2.4
11.5 6
23 12
46 24
115 60
230 120
460 240
dt < 10000 V
2
Resistor
Ω
15000
5600
2700
1500
560
270
150
/μs
2
3.4 Wiring guidelines
Suppressor values
W (power rating)
0.1
0.25
0.5
1
2.5
5
10
Installation
Capacitor
nF
15
470
100
150
470
1000
1500
75