User's Manual

975
Users Manual
20
Calibration
Calibration due dates are tracked using the Meter’s clock
and stored in non-volatile memory. Due dates can be
configured by the user from one to 365 days. When the
Meter reaches its calibration due date, it alerts the user
but will continue to operate.
The Meter’s CO and CO
2
sensors can be calibrated by
the user or returned to Fluke for service. See “Contacting
Fluke”. The recommended calibration interval is 1 month
for CO and 1 year for CO
2
.
Gas Canister and Regulator can be purchased from any
Calibration Gas Supplier allowing the users to calibrate
the CO and CO
2
sensors.
Install the calibration cap and attach the hose to the
correct gas canister; mixed CO and CO
2
for calibration
gas, Nitrogen for zeroing gas when calibrating CO
2
. See
Figure 4.
Note
Calibration gas is applied at the rate of ½
liter/minute for 2 minutes.
Regulator requirement: 0.5 liters/minute flow
rate.
For gas used for calibration, see Table 5.
Table 5. Gas for Calibration
Nominal ppm Min ppm Max ppm
CO 200 150 250
CO2 5000 4500 5000
Calibrating the CO and CO2 Sensors
Calibrate the CO and CO
2
sensors together, or
separately.
To simultaneously calibrate both sensors,
1. If not already in calibration mode, press , ,
and  simultaneously for 3 seconds to enter
calibration mode.
2. Press  [Yes] to initiate the calibration procedure.
3. Press  [BOTH].
The Meter display reads:
Calibration Procedure
Apply Nitrogen…
4. Apply ½ litre/minute of nitrogen for 2 minutes. Press
 [Cancel] to exit calibration.