CALIBRATION
IMPORTANT NOTE:
Electrochemical CO sensors slowly lose sensitivity over
time. A quick “bump test” should be performed with CO gas before each usage
to ensure proper instrument performance. It is also recommended to perform
a calibration at four month intervals to guarantee proper operation. A replace-
ment sensor should be installed if the unit can no longer be calibrated. In order
to perform a calibration, a calibration kit is required. This is available from Dwyer
Instruments, see below to order.
CALIBRATION ACCESSORIES
A-450-1 Calibration Kit with Regulator:
Includes case, Series 450 Handheld
Carbon Monoxide Monitor, regulator, tubing and A-450-2 Calibration Adapter.
For use with 17 liter gas tank. The regulator has a fixed flow rate of 0.5 L/min.
If a different Calibration Kit is used, a flow meter is required that can verify set-
ting the flow rate correctly to 0.5 L/min.
A-450-2 Calibration Adapter:
Adapter connects the regulator to the sensor
cover on the back of the CO Monitor.
A-450-3 Replacement Sensor
A-450-4 Aspirator Kit:
Includes aspirator bulb, adapter, tubing and probe.
A-450-5 Calibration Regulator Kit
: without Series 450 Carbon Monoxide
Monitor (same as A-450-1 except without Series 450 Handheld Carbon
Monoxide Monitor.
CALIBRATION PROCEDURE
1. Zeroing the Instrument: It is important that the instrument is in an area with
zero concentration of CO gas. Turn the instrument on and allow it to stabilize for
three (3) minutes. Press the key until the display reads CAL0. The upper
display should read between 0 and 12. If the upper display reads above 12, the
sensor may be bad and should be replaced – refer to SENSOR REPLACE-
MENT. Press the
and keys simultaneously. The display will momen-
tarily blink to show the value has been stored.
5
HOLD
STORE
ENTER
ON
OFF
BACKLIGHT
INDEX
HOLD
STORE
ENTER
ON
OFF
BACKLIGHT
INDEX
HOLD
STORE
ENTER
ON
OFF
BACKLIGHT
INDEX
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