Chapter
3
Technical Information
RFID write/read device RFH630 (HF)
18
©
SICK AG · Germany · All rights reserved · Subject to change without notice
8014957/YSU6/2016-01-08
Electrical installation
Remedial measures
The most common solution to prevent potential equalization currents on cable shields is to
ensure low-impedance and current carrying equipotential bonding. If this is not possible, the
following two solutions approach serve as a suggestion.
Important
We expressly advise against opening up the cable shields. Doing this means that the EMC
limit values can no longer be complied with and that the safe operation of the device data
interfaces can no longer be guaranteed.
a) Measures for widely distributed system installations
On widely distributed system installations with correspondingly large potential differences,
we recommend setting up local islands and connecting them using commercially available
electro-optical signal isolators
. This measure achieves a high degree of resistance to elec-
tromagnetic interference while at the same time complying with all the requirements of
EN 60950-1.
The ground loop is isolated by using the electro-optical signal isolator between the islands.
Within the islands, a stable equipotential bonding prevents equalizing currents at the cable
shields.
grounding point 1
Electro-
optical
signal
isolator
Electro-
optical
signal
isolator
PLC
Reading
clock sensor
grounding point 2
RFH630
shielded electrial cable
metal housing
fiber optic cable
