How do I calibrate my 4-20 mA outputs on the Surface Scatter 6 Analyzer?

Document ID

Document ID TE2336

Published Date

Published Date 27/05/2017
Question
How do I calibrate my 4-20 mA outputs on the Surface Scatter 6 Analyzer?
Summary
Surface Scatter 6 and 4-20 mA output calibration
Answer
The Surface Scatter 6 turbidimeter can self-calibrate the voltage or current limits to ensure a 0-100 mV output is truly 0-100 mV or a 4-20 mA output is exactly 4-20 mA. This programmed capability eliminates the need for a volt meter or multiimeter for output calibration.

Calibrating the recorder output involves a two-part
procedure. If a voltage output has been selected, the voltage limits are calibrated automatically by entering 4 DIAG. Microprocessor programming routines will measure and calibrate the output limits. This procedure sets the output to approximately ±1%. Fine tune by following the procedure in step 2, below.

If the 4-20 mA output is used, it is self-calibrated by selecting the 4-20 mA CAL output with the recorder output selector switch
a. Set the 4-20 mA switch to off (open). Because only one switch should be on at any one time, all other switches should be off (open) while the 4-20 mA CAL switch is on during self-calibration. There will be no recorder output while the 4-20 mA CAL switch is selected.
Using the keyboard, enter 3 DIAG.
1) a coarse adjustment to set the voltage or current until limit is completed.

2) a fine tuning is performed.

Using the recorder output selector switches, turn the 4-20 mA CAL
switch off, and then turn the 4-20 mA on. This will set the output to approximately ±1%. Fine tune the recorder output by following steps.

To fine tune the calibration, press 0 DIAG and observe the recorder reading.
The recorder should indicate the low end of the chart exactly. If the recorder zero reading is not correct, proceed as follows:
a. If the recorder zero reads too high, press 8 DIAG. The recorder reading will move downscale. When the recorder indicates zero, press any key.
b. If the recorder zero reads too low, press 7 DIAG. The recorder reading will move upscale.

When the recorder indicates zero, press any key.
Press 1 followed by the DIAG key and observe the recorder reading. The recorder should indicate the high end of the chart exactly. If the recorder reading is not correct, proceed as follows:
a. If the recorder full scale reads too high, press 6 DIAG. The recorder reading will move downscale. When the recorder reads full scale, press any key.
b. If the recorder full scale reads too low, press 5 DIAG. The recorder reading will move upscale. When the recorder reads full scale, press any key.