ABB IMASI13, Instructions Manual

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Automatic Adjustments and Corrections
into the 1 to 5 VDC needed to input to the analog input
module. The system power supply is protected from short cir-
cuits by fuses on the NTAI06 termination unit.
Function Codes
NOTE:
Refer to Appendix B for function code specification changes required
when replacing an IMASI03 module with an IMASI13 module.
FCs 215 and 216 in the controller configure the ASI module
and identify the active analog inputs. One FC 215 is required
for each ASI module. One FC 216 is required for each input
channel used on the ASI module. These function codes specify
the I/O expander bus address of the ASI module and the chan-
nel number on the module connected to a specific analog input
signal.
The type of the input and the zero and span in engineering
units must also be specified to ensure proper scaling and cor-
rections for calibration, cold junction compensation, and non-
linearity correction.
Add FC 215 and 216 to the controller to configure the ASI
module. Set FC 217 in the controller to calibrate the ASI mod-
ule or to set the user gain and offset values. Refer to the
Func- Func- Func- Func-
tion Code Application Manual
tion Code Application Manual tion Code Application Manual
tion Code Application Manual for more information.
Automatic Adjustments and Corrections
Input processing, calibration, point value calculations, lead
wire resistance adjustment, cold junction compensation, gain
and offset adjustment, and engineering units conversion are
all automatically performed by the ASI module.
Input Processing
Each A/D converter samples the input signal continuously
without need for a
start convert start convert start convert start convert command. The A/D output
register is updated at a rate determined by the internal filter
and can be ready at any time. The ASI module scans all A/D
converter output registers at a rate of about 180 milliseconds
including calibration and open circuit tests.
In addition to the input channels, the built-in cold junction
reference is read during normal input scanning.