Teledyne 3000TA - General purpose trace oxygen analyzer User Manual

Page 44

4 Operation

Model 3000TA

4-12

Teledyne Analytical Instruments

Shut off the gas pressure before connecting it to the analyzer, and

be sure to limit the pressure to 40 psig or less when turning it back on.

Readjust the gas pressure into the analyzer until the flowrate (as read on

the analyzer’s SLPM flowmeter) settles between 0.1 and 2.4 SLPM (ap-
proximately 0.2 - 5 SCFH).

If you are using password protection, you will need to enter your

password to gain access to either of these functions. Follow the instructions
in sections 4.3.3 to enter your password. Once you have gained clearance to
proceed, you can enter the

Zero

Span

function.

4.4.1 Zero Cal

The

Zero

button on the front panel is used to enter the zero calibration

function. Zero calibration can be performed in either the automatic or manual
mode. In the automatic mode, an internal algorithm compares consecutive
readings from the sensor to determine when the output is within the accept-
able range for zero. In the manual mode, the operator determines when the
reading is within the acceptable range for zero. Make sure the zero gas is
connected to the instrument. If you get a CELL FAILURE message skip to
section 4.4.1.3.

4.4.1.1

Auto Mode Zeroing

Press

Zero

to enter the zero function mode. The screen allows you to

select whether the zero calibration is to be performed automatically or manu-
ally. Use the

Δ∇ arrow keys to toggle between AUTO and MAN zero

settling. Stop when AUTO appears, blinking, on the display.

Zero: Settling: AUTO
To Begin

Press

Enter

to begin zeroing.

#### PPM Zero
Slope=#### ppm/s

The beginning zero level is shown in the upper left corner of the dis-

play. As the zero reading settles, the screen displays and updates information
on Slope (unless the Slope starts within the acceptable zero range and does
not need to settle further).

Then, and whenever Slope is less than 0.08 for at least 3 minutes,

instead of Slope you will see a countdown: 5 Left, 4 Left, and so fourth.
These are five steps in the zeroing process that the system must complete,
AFTER settling, before it can go back to

Analyze