Start-Up; Installation Guidelines - Belden HIRSCHMANN OZD Modbus Plus G12 Manuel

3 Start-Up

3 Start-Up

3.1 Installation guidelines

Electromagnetic compatibility (EMC)
Electromagnetic compatibility (EMC) covers all aspects
regarding the effects of radiated and received electrical,
magnetic, and electromagnetic emissions.
In order to prevent interference in electrical systems,
Interference suppression of switched inductances
Shield grid
over lamp
Fig. 5: Interference suppression of fluorescent lamps in cabinet
Arrangement of devices and cables
Reducing interference by providing adequate
space:
A simple yet effective way of reducing interference
is to separate devices and cables causing inter -
ference from those affected by interference.
Inductive and capacitive interference injection
decreases by the square of the distance between
the elements concerned. This means that doubling
the distance reduces the interference by a factor of 4.
If the arrangement of the various elements in a
building or in the switch cabinet is taken into con -
sideration at the planning stage, the cost of the
necessary interference suppression measures is
generally very low.
Version 04 07/2014
Shielded cable
Metal-encased
switch
Mains filter or
shielded mains cable
these effects must be reduced to a minimum.
The structural design and correct connection of bus lines
as well as the interference suppression of switched
inductances play a major role in limiting interference.
Suppressing switched inductances with fuses:
Switching inductances, e.g. in relays and fans,
generates interference voltages which are many
times higher than the switched operating voltage.
These interference voltages can affect electronic
devices.
The interference voltages of inductances must be
limited at their source of emission by means of
fuses (by connecting diodes or RC elements). Only
use interference suppressors which are intended
for the used relays and fans.
Cabinet lighting:
Use filament lamps (e.g. LINESTRA lamps) for the
cabinet lighting. Do not use fluorescent lamps
because they generate interference fields. If the
use of fluorescent lamps cannot be avoided, the
interference suppression measures shown in Fig. 5
must be implemented.
Please note:
Between an OZD Modbus Plus G12 ... and a power
switching element (e.g. contactor, relay, temperature
regulator, switch, etc.) a minimum separation of
15 cm is to be maintained.
This minimum separation is to be measured bet-
ween the outer edges of the components and in all
directions around an OZD Modbus Plus G12 ... .
The power supply wires (+24 VDC and m/0 V) for
the OZD Modbus Plus G12 ... must not be laid in
the same cable duct as cables for load circuits.
The wires (+24 VDC and m/0 V) should be twisted
together.
3.1 Installation guidelines
37