Measurement Computing PointScan 100 Series rev.1.0 - Manual (Page 10)

1-4 General Information 9-12-01 PointScan/100 User’s Manual
Isolation
Every PointScan/100 Series I/O module is isolated from ground and other modules for fault-free operation.
Additional levels of isolation (e.g. 500V channel to channel isolation) are provided with some modules.
Refer to the product specifications in the IO Toolkit online help system for more information.
Local Diagnostics
Local diagnostics can be performed through any available port while the gateway is responding to
messages from the other port. Diagnostic software, such as IO Toolkit, can be used to display the status of
the I/O registers.
Hot Swap Feature
I/O modules may be unplugged from their bases, even in live systems. PointScan/100 Series I/O modules
automatically self-configure from system memory. Analog I/O logic modules will automatically upload
and self-adjust to user calibration settings (if any are present) from the module base.
Calibration
All PointScan/100 Series analog I/O logic modules are factory calibrated over all supported ranges using a
regularly maintained set of standards. Factory calibration data is stored in permanent memory in the logic
module, and cannot be altered. User recalibration may be performed, but is necessary only if inaccuracy in
your field device is observed, or if any of the 100 ohm input shunts are replaced with low tolerance
resistors.
Each analog channel has span and offset calibration settings. Span is the "range" or "gain" of the channel.
Offset is the "zero" setting. Each reported analog I/O value is the product of the factory calibration value
times the user calibration value. The user calibration value is defined as:
(user span value * raw value) + user offset
The user span is a unity value (1) by default. The user offset is zero by default.
Note: All factory and user calibrations are performed in software. There are no adjustment
potentiometers inside the logic modules.
User calibrations are performed using the IO Toolkit utility. Refer to the IO Toolkit on-line help system for
information on calibrating PointScan/100 Series analog I/O.