Bacharach PCA 400 - Page 54

0024-9551 Revision 1
54
PCA
®
400 User Manual
IMPORTANT: “Measured” is the current CO reading, while “Applied” refers to the
known CO level which will be applied to the sensor for calibration purposes.
IMPORTANT: During the calibration process, open then adjust the knob on the
regulator to provide calibration gas to the target sensor. As you open the knob of
the regulator, the white ball inside of the ow meter will rise. Adjust the gas ow
so that the ball oats in the center of the ow meter (where the green and red hash
marks meet). This ensures sucient gas for calibration with minimal waste escaping
through the top of the ow meter.
Fig. 5-8: Adjusting the Flow Rate
Gas Flow Too Low
(Not enough to properly
calibrate).
Gas Flow Optimal
(Ball in ow meter is in the
“sweet spot”).
Gas Flow Too High
(Enough to calibrate but
gas is being wasted).
CAUTION: Unless instructed by the manufacturer or an authorized service provider,
DO NOT reset sensor gain ( ) during the calibration process.
1. Access the CO Calibration Menu
f To access the CO Calibration Menu: Calibration Menu  CO  CO + H
2
2. Apply 500 ppm CO to the Sensor
Attach a 500 ppm CO cylinder to the regulator. (For more information about the Gas Sensor
Calibration Equipment, see Figure 5-7.)
3. Adjust Flow Rate
Adjust the regulator to ensure that the flow rate is sufficient enough to calibrate the sensor.
(For more information about adjusting the ow rate, see Figure 5-8.)