Hirschmann OZD Genius G12-1300, User Manual

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Installation OZD Profi 12M ...
Release 01 07/2017
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The following ambient conditions must be fulfilled to ensure that the network
configuration functions correctly:
 The operating mode ”Redundant optical ring“ must be set at both optical
ports of all the OZD Profi 12M ... .

All repeaters in a ring must be connected to one another by fiber lines.
The ring may not include an RS 485 bus line.

The parameter MIN T
SDR
described in the PROFIBUS standard
EN 50170 must be set to a value ≥ 11on all terminals. This is usually the
case, but the setting should be checked if communication malfunctions
continuously arise.
 When configuring your network, select low bus subscriber addresses
wherever possible. This ensures that master timeout times which may
arise are kept as short as possible in the event of a malfunction.
 If a redundancy case occurs (e.g. a line break), there is a switching time
during which data can not be correctly transmitted. In order to ensure a
smooth transition, it is recommended that the frame repeat setting (Retry)
on the PROFIBUS master be set to at least 3.

After the error has been corrected, no frames should be present in the
network when the optical line is transformed back into an optical ring to
ensure that the process is completed smoothly. This condition can arise
when a master selects a device whose address has been configured, but
which does not physically exist.
The master tries to address this device cyclically and waits for a reply only
until the configured slot time has been exceeded (”GAP request“). The
OZD Profi 12M ... recognizes this condition and closes the optical line to
an optical ring in the middle of this request sequence. This results in two
configuration requirements for the redundant optical ring:
– The value of the parameter HSA (Highest Station Address) must be
set at all terminals so that between the bus address 0 and the value
HSA at least one address in the network has not been assigned to a
bus subscriber, i.e. so that there is at least one address gap. This
address gap can also be created by simply setting the value of the
parameter HSA so that it is at least one greater than the highest
number of subscriber bus addresses present in the network.
Note: If this requirement is not or no longer fulfilled, the optical line will no
longer be closed into a redundant optical ring after segmentation. The error
report (LED and signaling contact) of the two affected OZD Profi 12M ... is
not cancelled even after the error has been corrected.
– The slot time must be set to approximately twice the value required in
a non-redundant network. Refer to the manufacturer’s documentation
provided with the terminal or configuration software for details about
how to adjust the settings.