Measurement Computing PointScan 100 Series rev.1.0 - Manual (Page 27)

PointScan/100 User’s Manual 8-28-01 Analog Input Modules 7-1
Analog Input Modules 7
This section documents the following modules:
PointScan/102, PointScan/104
Note: It is not necessary to recalibrate analog I/O if a logic module is replaced.
Analog logic modules may be hot swapped and will not require recalibration. User calibration data is stored
in system memory outside of the analog module. Factory calibration data is stored in memory in the plug-in
logic module. Since all logic modules are calibrated to the same factory standards, recalibration is not
necessary if logic modules are moved or replaced.
PointScan/102
High Density 4-20 mA Analog Input Module
Overview
Sixteen 4-20 mA inputs provide 14 bit high resolution analog measurements. More information can be
found in the on-line help supplied with the IO Toolkit program.
Number of Channels 16 (14 bit resolution)
Input Range 4 - 20 mA
Input Impedance 100 ohms Note: input voltage drop = 2 volts at 20 mA
Wiring
A single input terminal is provided for each measurement channel. Care must be taken to externally provide
a suitable instrumentation ground for these single ended input circuits.
Current Shunts
Precision 100 ohm current shunts, beneath the hinged access door in the wiring base, pass current and
maintain loop integrity even if the module is unplugged. A spare shunt is provided and may be simply
inserted in place of any shunt that open-circuits as a result of a current overload.
I/O Registers
Function IOtech Registers Modbus Registers
Analog
Inputs AX0 – AX15 30001 – 30016