12. Optional Span Calibration
While the XT requires no calibration for its lifetime of 24 months there may be an occasion when
it is deemed necessary to carry out a calibration, for instance, if a self-test fails. To carry out the
span calibration the user requires the following additional equipment which can be purchased
from Honeywell Analytics.
•
Gas cylinder containing a known concentration calibration gas as follows:
•
A gas regulator supplying the gas at 300ml/min flow rate
•
Tubing for use between the regulator and the test adaptor (supplied)
Carry out the zero calibration procedure as described in Section 11. Only if the zero calibration
is successful can a span calibration be performed. At the end of the zero calibration procedure,
the test button must be pressed continuously for 5 seconds while the ( ) symbol is still flashing.
Connect the gas cylinder and test adaptor and apply the gas at 300 ml/min. The instrument will
display a 'C' (for calibration), and count down from '60' to '0'.
If the span calibration is successful the unit will give 2 beeps, 2 flashes and displays the Test Pass
icon ( ). If it fails the instrument gives a long beep, long flash and displays the Fail icon ( ) (the
calibration remains as it was before the span calibration was attempted).
XT Series Personal Gas Detector
(CO AND H
Toxic Gas
Calibration Concentration
H
S
2
CO
Span Calibration - Pass
S Versions Only)
2
25 ppm in air
100 ppm in air
Span Calibration – Fail
15