Modbus RTU RS-485
27
SFIDK.PS.023.D2.02
APPENDIX A & B
APPENDIX A
SI-units used in USM II
products
SITRANS F M MAGFLO
Volume flow:
m
3
/sec.
Totalisers:
m
3
SITRANS F C MASSFLO
Mass flow:
kg/sec.
Volume flow:
m
3
/sec.
Density:
kg/m
3
Temperature:
°
C
Fraction (A, B):
kg/sec.
Fraction A pct:
% (percent)
Totalizer 1 & 2:
kg or m
3
depending on totalizer mode (i.e. mass flow or volume flow)
Batch:
same as totalizers
Note
°
C for temperature is not strictly speaking an SI unit. This should be K (Kelvin), but K is of little
practical significance to most users, hence the use of C (Celsius).
APPENDIX B
USM II Error Pending and
Error Log
Reading Modbus address 2702 (USM II
Error Pending list
) and Modbus address 2729
(USM II
Error Log list
) provides detailed error information of the flowmeter.
The
Error Pending list
contains all actual errors and the
Error Log list
provides information
of all previous errors. Both lists are structured as 9 error records, each consisting of 6 bytes.
New errors will be placed first on the list (Error 1) and the rest will be shifted down the list.
Error No.:
A list of all error numbers can be found in the MAG/MASS manuals. No error is
represented by 0x7F.
Category:
0:
Information
1:
Warning
2:
Permanent
3:
Fatal
Timestamp:
Timestamp represents the time in minutes since the error occurred.
The following example is a reply containing the
Error Pending list
.
17,21,17,40,0,8,17,46,17,c0,0,8,
7f,7f,ff,0,0,0,7f,7f,ff,0,0,0,7f,7f,ff,0,0,0,7f,7f,ff,0,0,0,7f,7f,ff,0,0,0,
7f,7f,ff,0,0,0,7f,7f,ff,0,0,0
As can be seen, there are two active errors:
17,21,17,40,0,8
Error No.:
33 (dec) = Temp. too low
Category:
Warning
Timestamp: 8 minutes
17,46,17,c0,0,8
Error No.:
70 (dec) = Pickup phase
Category:
Fatal
Timestamp: 8 minutes
Note
7f,7f,ff,0,0,0 means no error.
Error list
