Allen-Bradley Compact 1769-IR6, Руководство пользователя

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Publication 1769-UM005A-EN-P
5-4 Diagnostics and Troubleshooting
Open-Wire or Short-Circuit Detection
The module performs an open-circuit or short-circuit input test on all
enabled channels on each scan. Whenever an open-circuit or short-circuit
condition occurs, the broken input bit for that channel is set in input data
word 6.
Possible causes of a broken input condition include:
•
the input device is broken
•
a wire is loose or cut
•
the input device is not installed on the configured channel
•
an RTD is internally shorted
•
an RTD is not installed correctly
Non-critical vs. Critical
Module Errors
Non-critical module errors are typically recoverable. Channel errors
(over-range or under-range errors) are non-critical. Non-critical error
conditions are indicated in the module input data table. Non-critical
configuration errors are indicated by the extended error code. See Table
5.3 Extended Error Codes on page 5-6.
Critical module errors are conditions that may prevent normal or
recoverable operation of the system. When these types of errors occur,
the system typically leaves the run mode of operation until the error can
be dealt with. Critical module errors are indicated in Table 5.3 Extended
Error Codes on page 5-6.
Module Error Definition
Table Module errors are expressed in two fields as four-digit Hex format with
the most significant digit as irrelevant (“don’t care”). The two fields are
“Module Error” and “Extended Error Information”. The structure of the
module error data is shown below.
NOTE
See Open-Circuit Flag Bits (OC0 to OC5) on page 4-4.
Table 5.1 Module Error Table
“Don’t Care” Bits Module Error Extended Error Information
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Hex Digit 4 Hex Digit 3 Hex Digit 2 Hex Digit 1