Over Or Under-Range Detection; Non - Critical Vs; Module Error Field - Spectrum Controls 1769sc-IF4IH User Manual

Section 9.5
Non-critical
vs. Critical
Module Errors
Section 9.6
Module Error
Definition Table
User' s Manual 0300215-03 Rev. A

9.4.2 Over or Under-Range Detection

Whenever the data received at the channel word is out of the defined operating range, an
over-range or under-range error is indicated in input data word 6. Possible causes of an
out-of-range condition include:
•
The input device is faulty.
•
The signal input from the input device is beyond the scaling range.
•
An open-circuit condition has been detected. Refer to page 6-3 for more details.
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.
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 or
program mode of operation until the error can be dealt with. Critical module errors are
indicated in Table 9-4 (Extended Fault Codes).
Analog module errors are expressed in two fields as four-digit Hex format with the most
significant digit as "don't care" and irrelevant. The two fields are "Module Error" and
"Extended Error Information". The structure of the module error data is shown below.
Table 9-2 (Module Error Table)
"Don't Care" Bits
15 14 13 12
0 0 0 0
Hex Digit 4

9.6.1 Module Error Field

The purpose of the module error field is to classify module errors into three distinct
groups, as described in the table below. The type of error determines what kind of
information exists in the extended error information field. These types of module errors
are typically reported in the controller's I/O status file. Refer to your controller manual
for details.
Chapter 9: Diagnostics and Troubleshooting
Module Error
11 10 9 8 7
0 0 0 0 0
Hex Digi t 3
Extended Error I nformation
6 5 4 3 2
0 0 0 0 0
Hex Di gi t 2 Hex Di git 1
9-3
1 0
0 0