Rockwell Automation 1762-IT4 Thermocouple/mV Input Module - Manual (Page 33)

Publication 1762-UM002A-EN-P - July 2002
Module Data, Status, and Channel Configuration 3-3
remains until the module begins converting analog data for the
previously accepted new configuration. When conversion
begins, the bit condition is reset (0). The amount of time it takes
for the module to begin the conversion process depends on the
number of channels being configured and the amount of
configuration data downloaded by the controller.
3. If A/D hardware errors prevent the conversion process from
taking place, the bit condition is set (1).
Open-Circuit Flag Bits (OC0 to OC4)
Bits OC0 through OC3 of word 4 contain open-circuit error
information for channels 0 through 3, respectively. Errors for the CJC
sensor are indicated in OC4. The bit is set (1) when an open-circuit
condition exists. See Open-Circuit Detection on page 4-4 for more
information on open-circuit operation.
Over-Range Flag Bits (O0 to O4)
Over-range bits for channels 0 through 3 and the CJC sensor are
contained in word 5, even-numbered bits. They apply to all input
types. When set (1), the over-range flag bit indicates an input signal
that is at the maximum of its normal operating range for the
represented channel or sensor. The module automatically resets (0)
the bit when the data value falls below the maximum for that range.
Under-Range Flag Bits (U0 to U4)
Under-range bits for channels 0 through 3 and the CJC sensor are
contained in word 5, odd-numbered bits. They apply to all input
types. When set (1), the under-range flag bit indicates an input signal
that is at the minimum of its normal operating range for the
represented channel or sensor. The module automatically resets (0)
the bit when the under-range condition is cleared and the data value
is within the normal operating range.
TIP
If the new configuration is invalid, the bit
function remains reset (0) and the module
posts a configuration error. See Configuration
Errors on page 4-5.