Flue Gas Analysis System

General Information

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.2Recessed Secondary Controls

NOTE: The recessed potentiometric controls are provided for calibration purposes. They should not be changed once calibration is estab- lished.

The SPAN control adjusts for manufacturing variations in sensitivity between elements and for various gases.

The ZERO control adjusts for zero meter reading with zero gas (air) flowing through the sample cell.

The ALARM control allows the point at which the unit goes into alarm to be adjusted anywhere between 0% and 5% combustibles as shown by the meter reading.

(Optional) The CAUTION control allows the point at which the unit goes into alarm to be adjusted anywhere within the range of the instrument as shown by the meter indication.

4.3Meter Trim

The small potentiometer (P5) located on the main circuit board below the meter is used to trim the meter to full scale deflection at the rated output. The potentiometric control is set at the factory.

4.4Analog Output

An analog (voltage or current) signal is provided for remote monitor- ing or recording. The type of signal is a customer option.

Voltage Output

0–1 Volt full scale or less.

NOTE: The remote meter or recorder should have an input impedance greater than 1K-Ohm.

Current Output

One of the following milliampere outputs may be provided:

TELEDYNE BROWN ENGINEERING

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Analytical Instruments

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Teledyne 9700 instruction manual Recessed Secondary Controls, Meter Trim, Analog Output