E8500 Instruction & Operations Manual
version 1.017
Page 34 of 49
ZERO TIME: This is the countdown time for the autozero procedure. The autozero cycle
time should set at 180 seconds.
SPAN TIME: When carrying out a span calibration, you must introduce the span gas for
an appropriate amount of time before the analyzer executes the span calibration. This
setting, which is the same for all sensors, controls this time interval. The span time is
indicated in seconds.
SPAN LOCKOUT: This controls access to the remaining span calibration menu
options. Span lockout prevents accidental or mistaken calibrations. Span lockout is
enabled and disabled by entering the 4-digit code of 1315.
SPAN XXXX: The remaining lines of the CALIBRATION MENU are used for carrying
out span calibrations of the CO, NO, NO2, SO2, H2S, VOC, NDIR and Stack Draft
sensors. For detailed use of these settings, please refer below.
A.
AUTOZEROING THE INSTRUMENT
When you turn the instrument on, wait two minutes to allow the analyzer to warm up
before carrying out the autozero countdown.
To start the autozero procedure, press the
CALIB
button and select
ZERO ALL
SENSORS
. Make sure that the analyzer pump is pulling in air.
At the end of the autozero period the E8500 Plus reads the output of all gas sensors
and sets them all to zero, with the exception of the oxygen that it sets to 20.9%.
Consequently, it is very important that at the moment of "zeroing", the environment is
clean from traces of carbon monoxide or other gases.
If no error messages appear at the end of the countdown, proceed with your
measurements.
B.
SPAN CALIBRATION
You must always span calibrate the instrument every time you replace a sensor. At a
minimum, you should perform a span calibration of the instrument once every 12
months. For greater accuracy you should check the calibration of the instrument before
and after each emissions test. The parameters that require a span calibration are:
carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, sulfur dioxide, hydrogen
sulfide, volatile organic compounds, hydrocarbons, and draft. You can carry out all span
calibrations in sequence or just one, if you wish.
TO SPAN CALIBRATE THE ANALYZER, IT IS BEST TO USE ONLY SINGLE
GAS MIXTURES WITH EITHER NITROGEN OR AIR BALANCE.
