Allen-Bradley Compact 1769-IR6, Руководство пользователя

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Publication 1769-UM005A-EN-P
4-4 Module Data, Status, and Channel Configuration
Open-Circuit Flag Bits (OC0 to OC5)
Bits OC0 through OC5 of word 6 contain open-circuit error information
for channels 0 through 5, respectively. For an RTD input, the bits indicate
either an open-circuit or short-circuit condition when set (1). For a
resistance input, the bits indicate an open-circuit when set (1).
Over-Range Flag Bits (O0 to O5)
Over-range bits for channels 0 through 5 are contained in word 7,
even-numbered bits. They apply to all input types. When set (1), the
over-range flag bit indicates an RTD temperature that is greater than the
maximum allowed temperature or a resistance input that is greater than
the maximum allowed resistance for the module. The module
automatically resets (0) the bit when the data value is again within the
normal operating range.
Under-Range Flag Bits (U0 to U5)
Under-range bits for channels 0 through 5 are contained in word 7,
odd-numbered bits. They apply only to RTD input types. When set (1),
the under-range flag bit indicates an RTD temperature that is less than the
minimum allowed temperature. The module automatically resets (0) the
bit when the data value is again within the normal operating range.
NOTE
Short-circuit detection for direct resistance inputs is not
indicated because 0 is a valid number.
NOTE
There is no under-range error for a direct resistance input,
because 0 is a valid number.