Mi3 offers a form of field calibration via Offset and Gain parameters.
When to use
1. Adjust temperatures values to maintain factory specifications.
2. Fine adjustment when using multiple sensors in an array (cancel out "within specification" deviation).
3. Calibrating to a process, where changing the emissivity setting is not permitted (defined for the material).
How to Use
Adjustment can be performed using push buttons via the Mi3 COMM box (head menu), specific ASCII commands using a suitable terminal program, or via free supplied software DTDM v6.
Commands
DO - device offset in the range -200 to +200 deg C
DG - device gain as a factor between 0.8 and 1.2
Considerations
For a simple correction at a single process temperature - adjust offset only
For a correction over a range of process temperatures - adjust offset and then gain
General Principle - Offset Only
Offset adjustment should be performed at the the desired single process value - multiple iterations may be required
General Principle - Offset and Gain
Offset adjustment should be performed at the lowest process value in consideration as first step.
With the offset adjustment set in the sensor, the gain value should be adjusted a higher (generally the highest) process value in consideration.
Special Note
Offset and gain correction affects the temperature values as opposed to any energy value behind the final calculated temperature.
Multiple iterations may be required with a multi sensor array to achieve the desired outcome.
All values can be restored.
The basic factory calibration of the device cannot be disturbed by performing an offset and gain correction.