Photometric Analyzer

Operation /Control Unit 3

 

 

 

 

 

 

 

 

 

AUTOCAL FILSOLL HOLD

CAL-HOLD-TIMER MORE

Select MORE and press ENTER one more time

ALGORITHM APPLICATION

MORE OUTPUT: 4MA

Now you will be able to select the APPLICATION and ALGO- RITHM set-up functions.

3.8.1The Set Range Screen

The Set Range screen allows reprogramming of the three analysis ranges and the calibration range (background fluid, low end of range, high end of range, and % or ppm units). Original programming is usually done at the factory according to the customer’s application. It must be done through the RS-232 port using a computer running a terminal emulation program.

Note: It is important to distinguish between this System programming subfunction and the Range button function, which is an operator control. The Set Range Screen of the System function allows the user to DEFINE the upper and lower limits of a range AND the application of the range. The Range button function only allows the user to select or define the limits, or to select the application, but not to define the application.

Normally the Model 5000BF is factory set to default to manual range selection, unless it is ordered as a single-application multiple-range unit (in which case it defaults to autoranging). In either case, autoranging or manual range selection can be programmed by the user.

In the autoranging mode, the microprocessor automatically responds to concentration changes by switching ranges for optimum readout sensitivity. If the upper limit of the operating range is reached, the instrument automati- cally shifts to the next higher range. If the concentration falls to below 85% of full scale of the next lower range, the instrument switches to the lower range. A corresponding shift in the DC concentration output, and in the range ID outputs, will be noticed.

The autoranging feature can be overridden so that analog output stays on a fixed range regardless of the contaminant concentration detected. If the concentration exceeds the upper limit of the range, the DC output will saturate at 1 V dc (20 mA at the current output).

However, the digital readout and the RS-232 output of the concentra- tion are unaffected by the fixed range. They continue to read beyond the full-

Teledyne Analytical Instruments

Part I 3-29

Page 57
Image 57
Teledyne M5000B operating instructions Set Range Screen