Output Calibration

 

Accurate retransmission of the selected parameters can only be obtained through calibrating both of the analog outputs. This is done at the factory prior to shipment, however it is a relatively simple procedure that can be performed in the field if desired.

 

To perform a calibration, a multimeter with a current input is required. Please keep in mind that the accuracy of the instrument used to calibrate the outputs is directly related to the accuracy of the outputs after calibration, so a meter calibrated against NIST (National Institute of Standards and Technology) standards is preferred. Before performing any calibrations, all other devices must be disconnected from the analog outputs. Multiple devices on the outputs will cause inaccurate measurement of current.

 

SSi suggests that this device should be calibrated on a routine basis, such as once a year or as prescribed by the user’s quality system requirements.

 

Zero Calibration

To calibrate the zero/span range for an output:

1. Attach a measuring device to the selected output.

2. Select “Zero output 1 or 2” depending on the output being calibrated

3. Press the “Prep for Cal” button.

4. Let the unit output what it has set for the zero measurement, and note the reading on your attached multimeter.

5. Touch the value being displayed next to the “Enter measured value” enter the reading from your multimeter.

6. Push the “Calibrate” button.

This will offset the mA output of the instrument in an amount that results in an exact output of 4.000 mA. When the calibration is complete, the multimeter should be reading 4.000 mA (+/- .005). The zero calibration is complete.

 

Span Calibration

To calibrate the span:

1. Verify that the multimeter is still be attached to the selected output.

2. Select “Span output 1 or 2” depending on the output being calibrated

3. Press the “Prep for Cal” button.

4. Let the unit output what it has set for the span measurement, and note the reading on your attached multimeter.

5. Touch the value being displayed next to the “Enter measured value” enter the reading from your multimeter.

6. Push the “Calibrate” button.

This will offset the mA output of the instrument in an amount that results in an exact output of 20.000 mA. When the calibration is complete, the multimeter should be reading 20.000 mA (+/- .005). The span calibration is complete.

The multimeter will display the actual output from the instrument, and if it is not within the desired tolerance it can be calibrated using the same procedure as above.