6 Application example: Modbus TCP
6.5 Evaluation of module diagnostics
134
XI/ON: XNE-GWBR-2ETH-MB
10/2011 MN05002008Z-EN
www.eaton.com
6.5.2
Module diagnosis (0×A000 to 0×A400)
For each module, 64 Bytes = 32 registes are reserved for diagnostic messages.
•
Module 3
: XN-2AI-THERMO-PI
The module has 2 bytes of diagnosis data, these are shown in
register 0×A060
→
register 0×A060 = 0×0200
→
"open circuit" at channel 1..
•
Module 9:
XN-1SSI
The module has 1 byte of diagnosis data, these are shown in
register 0×A120
→
register 0×A120 = 0×0002
→
The diagnosis shows an "open circuit" at channel the SSI module, because no SSI-
encoder is connected.
I
Figure 65:
module diagno-
sis, module 3
A
diagnosis byte
channel 0
B
diagnosis byte
channel 1
Table 72:
XN-2AI-
THERMO-PI
Diagnosis byte
Bit
Diagnosis
n (channel n),
n=1,2
0
Measurement value range error:
– Threshold: 1 % of the positive measurement range limit value
– With type K, N and T sensors, the “Underflow” diagnostic
signal is generated on temperatures below -271.6 °C.
1
Wire break (only in temperature measurements)
2 to 7
reserved
Figure 66:
module diagno-
sis, module 9
A
diagnosis byte
channel 0
B
diagnosis byte
channel 1
A
B
A
B