Siemens SIPART PS2 PA 6DR55 Series, Руководство по эксплуатации

Страница: 195 / 292

Functions/operations using PROFIBUS PA
11.3 Cyclic data transfer
SIPART PS2 with PROFIBUS communication
Operating Instructions, 09/2007, A5E00127926-07
195
11.3.3 Useful data through PROFIBUS
Cyclic useful data
The positioner can exchange a combination of the following cyclic useful data through
PROFIBUS:
Name
German
English
Abbreviation Direction from the
positioner's point of
view
Length in
byte
Comprising:
Sollwert Setpoint SP Input 5 Value/Status
Istwert RB Output 5 Value/Status
Position discrete POS_D Output 2 Value/Status
Aktorzustand Checkback CB Output 3 Value
Fernkaskade Eingang Remote Cascade Input RCAS_IN Input 5 Value/Status
Fernkaskade Ausgang Remote Cascade
Output
RCAS_OUT Output 5 Value/Status
Setpoint
The setpoint is divided into a floating point value (4 bytes) and the corresponding status (1
byte, see further below).
Actual value
The actual value indicates the valve position. The actual value is divided into a floating point
value (4 bytes) and the corresponding status (1 byte).
Position discrete
The discrete valve position is displayed as a value (1 byte) having the following meaning:
0 = not initialized
1 = valve closed
2 = valve open
3 = valve in the intermediate position: Even this value has a status (1 byte).
Checkback
The checkback is displayed in 3 bytes in a bit-coded format:
Bit Meaning of "1" Remarks
0 0 Device in the fail safe position The position is determined by the "49.FSTY"
parameter.
1 Request for on-site operation Reports that a button has been pressed.
2 The device is operated on-site. The device is parameterized on-site, e.g. using the
"1.YFCT" parameter or is not initialized.