VEGA VEGACOM 558 Ethernet - Manual (Page 23)

VEGACOM 558 Ethernet 23
on
VEGAMET
513
!
ESC OK
- +
100 %
CONNECT
on
VEGAMET
513
!
ESC OK
- +
100 %
CONNECT
on
VEGAMET
513
!
ESC OK
- +
100 %
CONNECT
on
VEGAMET
513
!
ESC OK
- +
100 %
CONNECT
Data image in VEGACOM 558
all measured values
from VEGAMET #2
VEGACOM 558 collects measured values of
the VEGAMET 513, 514, 515 and 614 signal
conditioning instruments (via DISBUS) or
VEGALOG 571 (via LOGBUS) and stores
them temporarily for collection via MODBUS /
TCP.
The way the measured values are stored in
the temporary storage of VEGACOM 558 for
the higher-priority processing system de-
pends on the selected configuration. It de-
pends on whether VEGACOM 558 is
connected to DISBUS or LOGBUS.
VEGACOM 558 follows the "Open MODBUS /
TCP Specification" release 1.0 from Schnei-
der Electric. This standard is supported by
many process control systems, remote IO’s,
visualisation programs and OPC servers.
Note:
When connecting to DISBUS, the storage of
measured values can be determined addi-
tionally via the HTML configuration page
"General".
Beside the measured values, it is also possi-
ble to call up the status of the contact inputs
and outputs via VEGACOM 558.
Call up of the measured values via:
- Function code 04 (= Read Input Registers)
Call up of the switching conditions via:
- Function code 01 (= Read Coil Status) or
alternatively via
- Function code 02 (= Read Input Status).
Grouping of measured values acc. to VEGAMET
addresses
all measured values
from VEGAMET #15
all measured values
from VEGAMET #1
6.1 Storage of measured values
when connected to DISBUS
The addressing of the measured values for
Modbus systems is "word-oriented". In
VEGACOM 558, a measured value is repre-
sented by two words, the first word includes
the real measured value, the next higher
word the associated status information. In the
standard, the term "register word” is also
used instead of the term "word”. The ad-
dressing is done via existing library calls of
the process control system (e.g. Modicon).
As already mentioned, the storage of meas-
ured values for VEGAMET signal conditioning
instruments can be influenced by the user.
For this purpose, a connection to VEGACOM
558 must first be provided via a web
browser. By activating the entry "DCS 1-7
from MET 1, …" in the section "storage of
measured values for MODBUS / TCP” in the
HTML page "General", the measured values
are saved in rising sequence acc. to the
VEGAMET addresses.
6 VEGACOM 558 as Modbus / TCP server
Temporary memory
of VEGACOM 558