Siemens 3VF Series Communications Manual page 68

Communication System Manual
The lines are an extract from DB240 (DBAT, data block for request processing) designed to explain the
enabling and priority assignment of read requests which are to be processed "cyclically". Messages are
enabled from DW100 to DW107 by setting a "1". In the example given here, messages 11, 12, 13 and
14 are enabled in DW 100. The messages are classified according to priority in DW 108 to DW 131.
Priorities have already been assigned but can be changed according to requirements. The message
numbers increase from left to right within the DB, in the same way as for the enable. Priority
assignment entails sending requests with a higher priority more frequently than messages with a lower
priority. The enable and one priority assignment must be allocated in order to generate a valid
message. In the example provided, this means that only requests 11 - 14 are enabled and these are
assigned to priority 1 by default.
This type of enabling permits the program to be adapted to a wide range of conditions, e.g.
visualization with several windows which only ever display a small number of values. Only the required
values need to be updated here, thus allowing for a considerable increase in performance.
3.5.3.4.3 Circuit-breaker parameterization (writing parameters)
The data which the circuit-breaker is currently using as parameters are stored in DB240. The data to be
transferred to the 3WN6 are stored in DB230. FB10 now checks on every call whether the data in
DB230 and DB240 are consistent. If a discrepancy is detected, a bit for writing requests is set. The new
values in DB230 are then transferred to 3WN6 and stored as old values in DB240. The request bit is
reset. If a new value is to be parameterized, it must therefore be entered at the correct position in
DB230. The position is calculated in the same way as for DB80 and DB81:
DW no. = 2 x T-Nr.+1
Example: "z" release setting current, T-Nr. 65, tripping value 20 kA
Enter 20000 in DW65*2+1 = DW131 of DB230
Special cases: The parameters for additional functions 111/112 must be entered as follows:
111: in DL222 of DBSZ
112: in DR225 of DBSZ
The differences occur as these are the only parameterization messages to parameterize two words. All
others parameterize only the second word.
Attention: Because parameter I
message, only one of these options is supported in order to avoid parameter inconsistencies. The
parameter for I can therefore only be transferred using the acyclic message and an entry in DW99 of
r
DBAT (which would trigger cyclical parameterization) does not change the parameter in the circuit-
breaker.
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can be assigned using either the cyclic or the acyclic part of the
r
© Copyright Siemens AG 1998. All rights reserved.
3WN6 Circuit-Breakers
Version 1.0 (02/98)