User's Manual
Table Of Contents
- SIMATIC RF300
- Legal information
- Table of contents
- 1 Introduction
- 2 Safety information
- 3 System overview
- 4 Planning the RF300 system
- 4.1 Fundamentals of application planning
- 4.1.1 Selection criteria for SIMATIC RF300 components
- 4.1.2 Transmission window and read/write distance
- 4.1.3 Width of the transmission window
- 4.1.4 Impact of secondary fields
- 4.1.5 Setup help of the readers of the second generation
- 4.1.6 Permissible directions of motion of the transponder
- 4.1.7 Operation in static and dynamic mode
- 4.1.8 Dwell time of the transponder
- 4.1.9 Communication between communications module, reader and transponder
- 4.2 Field data for transponders, readers and antennas
- 4.3 Installation guidelines
- 4.4 Chemical resistance of the transponders
- 4.5 Guidelines for electromagnetic compatibility (EMC)
- 4.1 Fundamentals of application planning
Planning the RF300 system
4.5 Guidelines for electromagnetic compatibility (EMC)
SIMATIC RF300
System Manual, 07/2016, C79000-G8976-C345-0x
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4.5.6
Prevention of interference sources
A high level of immunity to interference can be achieved by avoiding interference sources.
All switched inductances are frequent sources of interference in plants.
Suppression of inductance
Relays, contactors, etc. generate interference voltages and must therefore be suppressed
using one of the circuits below.
Even with small relays, interference voltages of up to 800 V occur on 24 V coils, and
interference voltages of several kV occur on 230 V coils when the coil is switched. The use
of freewheeling diodes or RC circuits prevents interference voltages and thus stray
interference on conductors installed parallel to the coil conductor.
Figure 4-16 Suppression of inductance
Note
All coils in the cabinet should be suppressed. The valves and motor brakes are frequently
forgotten. Fluorescent lamps in the control cabinet should be tested in particular.