5
Chapter 3
Operation
Keypad Functions
ON/OFF Key
Press to turn the Model 7515 on and off. During
the power up sequence the display will show the
following: Model Number, Serial Number,
Software Revision, and Last Date Calibrated.
Sample Key
Press and release to start the sample, then press the
END
key to stop the sample.
Stats Key
Press to view the minimum, maximum and
average of the last sample taken.
CAL Key
Press to begin the field-calibration process. To re-
calibrate in the field, first connect zero gas to the
instrument and open the regulator. Then use the
ST
and ENTER keys to select ZERO. The
instrument will automatically make zero itself after
one minute.
After zeroing the sensor, connect span gas to the
instrument and open the regulator. Then use the
ST
and ENTER keys to select SPAN. The
instrument will take one minute to make a reading.
Then use the
ST
and ENTER keys to adjust the
concentration displayed on the instrument to
match the concentration on the gas cylinder.
