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UMG 509-PRO
www.janitza.com
8. Interfaces
The device has the following interfaces through
which it can be connected to other devices:
·RS-485
·Profibus
·Ethernet
8.1
Shielding
Provide a twisted and shielded cable for connec-
tions via the interfaces and observe the following
points for shielding:
·Ground the shields of all cables leading into the
cabinet at the cabinet entrance.
·Connect the shield to a noiseless ground and
ensure a large surface area with good conduc-
tivity.
·Mechanically restrain the cables before the
grounding clamp to prevent damage from cable
movement.
·Use suitable cable glands, for example PG
glands, to lead the cable into the switchboard
cabinet.
Cable
Strain relief
Braided shielding of the
cable
Grounding clamp
Noiseless ground
Fig. Shielding design at the cabinet entry.
WARNING
Risk of injury due to high currents and high
electrical voltages!
Atmospheric discharge can cause transmission
errors and dangerous voltages on the device.
Therefore please abide by the following:
·
Connect the cable shielding to functional
earth (PE) at least once.
·
For larger sources of interference or fre-
quency converters in the switchboard
cabinet, connect the shielding to functional
earth (PE) as close to the device as possible.
·
Comply with the maximum cable length of
1,200 m at a baud rate of 38.4 kbps.
·
Use shielded cables.
·
Route interface cables spatially separated
or additionally insulated from mains volt-
age-carrying system components.
