Samson 4785, Монтаж и эксплуатация

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7. How to implement the PROFIBUS Master Class 1
7.1 Device Database Files (GSD)
The device database files are provided as text files: SAMS0688.GSD for profile 3.0 or
SAMS3785.GSD for profile 2.0. The files are available from SAMSON AG under product
no. 1400-7417 on a 1.44 MB disc (3 1/2"). Alternatively, they can be downloaded from
the following sites: http://www.samson.de or http://www.profibus.com.
The device database files enable the standardized implementation of the SAMSON
Type 3785 Positioner in the programming and configuration environment of a Master
Class 1 as PROFIBUS slave unit (example: SIEMENS Simatic Step 7, HWConfig). Via the
GSD, the Master Class 1 is informed about the basic possibilities of cyclic data exchange
with the slave unit – in this case, the Type 3785 Positioner.
7.2 Data exchange
According to the PROFIBUS PA device profile for electropneumatic actuators, a total of 7 dif-
ferent cyclic parameter combinations is available for the exchange of data. One of these
seven possible combinations must be selected via the programming and configuration envi-
ronment of the Master Class 1.
The terms "output" and "input" refer to the control system/Master Class 1.
Variant 1: Module = "SP" 0xA4 or 0x82, 0x84, 0x82, 0x82
Output value (Output)
Byte 0 1 2 3 4
Octet 1
Sign,
Exponent
Octet 2
Exponent,
Fraction
Octet 3
Fraction
Octet 4
Fraction
Octet 5
SP, Value
(Floating Point, IEEE)
Status
Variant 2: Module = "RCAS_OUT, RCAS_IN" 0xB4 or 0xC2, 0x84, 0x84, 0x82, 0x8C
Input value (Input)
Byte 0 1 2 3 4
Octet 1
Sign,
Exponent
Octet 2
Exponent,
Fraction
Octet 3
Fraction
Octet 4
Fraction
Octet 5
RCAS_OUT, Value
(Floating Point, IEEE)
Status
38
EB 8382-2 EN
How to implement the PROFIBUS Master Class 1