4 Setting Up
4.9 Connecting the function ground and the shield of the bus cable
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Version 04 05/2014
32
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On the 7-pin terminal block on the top of the repeater,
the unconnected pins of a relay can be used as signal
contacts.
When the OZD Profi 12M … PRO is working correctly,
the contact is closed.
If there is an error or a power failure, the contact is
opened.
Note:
To connect the signal contact lines, the 7-pin screw
terminal block on top of the device can be released from
the device.
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The following problems with the network and the
repeater can be signalled by means of the signal
contact:
Supply voltage
– interrupted
– incorrectly connected
Internal device errors
Received data
– no input signal at channel 2 (optical)
– no input signal at channel 3 (optical)
– faults on channel 1 (electrical)
Redundant optical ring
– interruption of an optical fiber
– a repeater fails
For a detailed description of the faults signaled, see
chap. 5, page 35.
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Threshold values of relay contact
– maximum switching voltage: 60 VDC; 42 VAC
– maximum switching current:: 1.0 A
– maximum switching capacity: 30 W (ohmic load)
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The voltage connected to the relay must correspond
to a
safety extra-low voltage (SELV)
in accordance
with IEC / EN 60950 and the regulations of NEC,
Class 2, in accordance with UL/CSA certification.
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Please be sure to use the correct pin assignment for
the 7-pin terminal block. Make sure that the electrical
insulation of the connection cables of the signal cont -
acts is sufficient.
Incorrect connections can destroy the repeater.
4.10 Connecting the signal contact lines (optional)
+24 V(L1+)
0 V
FAULT
+24 V(L2+)
0 V
Fig. 12: Signal contact – pin assignment on the 7-pin terminal
block
Note:
See chapter “Laying cables outside of buildings” on
page 22.
Warning !
There is no contact separation between the bus
lines and the connection for the function ground.
Therefore please observe the fol low ing safety
instructions:
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Do not use bus lines to connect repeaters to device
parts which have a different earth potential.
The diff erent voltages could destroy the repeaters!
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Avoid electrical bus lines, which are partly or entirely
laid outside buildings. If lightening strikes close by,
this could destroy the repeaters. Use F/O cables for
bus connections outside buildings!
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The shield of the bus cable, together with the func-
tion ground connection, must be connected to an
equipotential rail in the switch cabinet. The equipo-
tential rails of the switch cabinets, which are connec-
ted to one another by means of an electrical
RS 485 bus cable, must have a low-impedence
connection to one another.
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The function ground of the repeater is effected by
means of the
connection of the screw terminal
block on top of the device.
4.9 Connecting the function ground and the shield of the bus cable