Endress+Hauser prowirl 77, Руководство по эксплуатации

Страница: 22 / 64

Status codes for flow and totalizer
Prowirl 77 uses part of the status codes defined by the PROFIBUS user organization
(PNO) (see PNO specification “PROFIBUS-PA Profile for Process Control Devices;
General Requirements V2.0”):
IEEE floating point numbers
Measured values are transmitted to the master Class I (e.g. PLC) in the IEEE-754
number format as shown below:
Formula = (-1)
VZ
* 2
(Index -127)
* (1 + Mantissa)
Example: 40 F0 00 00 hex. = 0100 0000 1111 0000 0000 0000 0000 0000 binary
Value = (-1)
0
* 2
(129-127)
* (1 + 2
-1
+ 2
-2
+ 2
-3
)
= 1 * 2
2
* (1 + 0.5 + 0.25 + 0.125)
= 1 * 4 * 1.875 = 7.5
Byte n Byte n + 1 Byte n + 2 Byte n + 3
Bit 7 Bit 6 Bit 0 Bit 7 Bit 6 Bit 0 Bit 7 Bit 0 Bit 7 Bit 0
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
Index Mantissa Mantissa Mantissa
Status code
hex. (dez.)
Meaning Device status
0Fh (15) device failure (low and high limit bit set) BAD
1Ch (28) out of service (no limit bit set) BAD
1Fh (31) out of service (low and high limit bit set) BAD
08h (8) not connected BAD
40h (64) non-specific (no limit bit set) UNCERTAIN
42h (66) non-specific (high limit bit set) UNCERTAIN
43h (67) non-specific (low and high limit bit set) UNCERTAIN
80h (128) O.K. (no limit bit set) GOOD
81h (129) O.K. (low limit bit set) GOOD
82h (130) O.K. (high limit bit set) GOOD
83h (131) O.K. (low and high limit bit set) GOOD
5 Communication Prowirl 77 PROFIBUS-PA
22 Hauser