Owner's manual

Appendix C _________________________________________________________ Modbus Reference
VAISALA _______________________________________________________________________ 181
Status Registers (Read-Only)
Table 49 Status Registers
Name
Address
Description
Fault status
0513
1 = No errors
Online status
0514
1 = Online data available
Error code (bits 15…0)
0516
Bit field that represents the
error codes listed in Table 33
on page 147
. Active errors are
set to 1. For example, if bit 14
is set to 1, error code E14 is
active.
Error code (bits 31…16)
0517
Error information can retrieved also with function code 08, sub-function
02.
NOTE
Basic status information of the DMT34
5/346 transmitter is also available
with the Read Exception Status function code 07. For details, see section
Exception Status Outputs
on page 182.
Configuration Registers
Configuration parameter registers are used to configure the measurement.
Writing out-of-range values is silently ignored.
Table 50 Configuration Parameter Registers
Name
Float
Integer
Valid Range
Pressure setting default
value
0769…0770
1025 (×1)
0…9999 hPa
Pressure setting
temporary value
0771…0772
1026 (×1)
0…9999 hPa
Sensor purge interval
0773…0774
1027 (×1)
10…2880 min
Molecular weight for
ppm
w
calculation
0775…0776
1028 (×0.001)
0…999.999
g/mol
If you modify the pressure setting repeatedly, modify the temporary
value at register 0771...0772 (1026) instead of the permanent setting at
register 0769…0770 (1025). Set the temporary value to zero to return to
the default pressure setting.
Non-metric units are not available on Modbus. If they are needed,
calculate the conversion outside the transmitter.