KROHNE UFC 030 PROFIBUS PA - Manual (Page 6)

Supplementary documentation UFC030 with PROFIBUS-PA
KROHNE Messtechnik GmbH & Co. KG · Ludwig-Krohne-Str. 5 D-47058 Duisburg 6/17
Tel.: 0203-301 309 Fax: 0203-301389 · e-mail: [email protected]
ModeTot = 1 totalizes only positive values.
ModeTot = 2 totalizes only negative values.
ModeTot = 3 totalizer is stopped, no totalization will be done.
ModeTot
>
3 not allowed
6. The standard block confi guration may be changed by the customer but using the default settings is highly
recommended. If the standard block configuration should be changed by the customer a acyclic master tool
must be used to change the “channel parameter” value of the block which should be connected to another
transducer output value.
4.3.2
Profile specific GSD file: PA_9741.GSD
The functionality of the profile specific GSD file is limited. This GSD file includes only three blocks:
Volume Flow, Speed of Sound (Sound Velocity) and Volume Flow totalizer.
You need the PA_9741 file to use this functionality. Before this, the communication has to be projected and it has to
be switched from “full functionality” to “interchangeable basic configuration” by using a master class 2 tool
(IDENT_NUMBER_SELECTOR: Slot 0, Index 40 change byte value from 1 to 0). After this has been done, the
device has to be projected by using the PA _9741 file.
4.4 Cyclic data exchange
During network configuration the user has to define which function block outputs of the UFC030 (UFC 3 Beam)
should be transferred cyclically to the master. The following function block outputs are available in this order:
1. Volume Flow and Status
2. Speed of Sound und Status
3. Volume Totalizer and Status
4. CORR. Volume Flow or HEAT Flow * and Status
5. CORR. Volume- or HEAT- Totalizer * and Status
•
depends on the current device type selection
Note: If a function block output is chosen for cyclical data transfer the value "Not_a_Number" (0x7FFFFFFF) will be transmitted if the
function block itself is not available (due to the current device type selection). If so the status is "Bad-Out of Service".
Network configuration will be done by a master class 2 tool using one of the GSD files described above. The function
block outputs which should be transmitted cyclically may be chosen without any restriction. The order of transmission
always remains the same even if a function block is defined as an “Empty” block (if so no function block output data
will be send to the master and all function block outputs following the “Empty” block will move up one position).
4.5 Data Structure of Function Block Output Values
The data structure of function block outputs consists of 5 bytes: a 4 byte float value (Float Format according IEEE
Standard 754 Short Real Number) followed by a 1 byte status value. If all 5 function block outputs have been
projected (see above), 25 byte will be transmitted.
4.5.1
Float Value
First an example of the float format:
Byte n Byte n+1 Byte n+2 Byte n+3
Bit7 Bit6 Bit7 Bit6 Bit7 Bit7
VZ 2 7 2 6 2 5 2 4 2 3 2 2 2 1 2 0 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 2 -8 2 -9 2 -10 2 -11 2 -12 2 -13 2 -14 2 -15 2 -16 2 -17 2 -18 2 -19 2 -20 2 -21 2 -22 2 -23
Exponent Mantisse Mantisse Mantisse
Example:
40 F0 00 00 (hex) = 0100 0000 1111 0000 0000 0000 0000 0000 (binary)
Formula:
Value = (-1)
VZ
* 2
(Exponent - 127)
* (1 + Mantisse)