Bacharach H25-IR, Руководство по эксплуатации и техническому обслуживанию

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Calibration H25-IR
24
Instruction 3015-5286
3.3 External Calibration
External calibration uses a customer-supplied leak source that matches the gas to be monitored. Properties of
the leak source must be entered by the operator using the EXT RATE and EXT GAS TYPE functions as
described in Section
3.1.2 External Calibration Selection and Setup . The EXT RATE entry is the number
displayed as the “target” value during calibration.
IMPORTANT! The operator is responsible for ensuring that the external leak-rate value has been corrected
for daily changes in ambient temperature and pressure at the time of calibration. It is also the operator’s
responsibility to ensure that a good calibration has been performed.
1. Turn ON instrument and allow it to complete its 120 second warm-up.
2. Press the front panel CAL button to display the Calibration screen. Note that the display must be
reading a leak rate of “0.00” when the CAL button is pressed; otherwise, the message “LEAK RATE
MUST BE ZERO TO CALIBRATE” will appear. If necessary, press the ZERO button to zero the gas
display before pressing CAL .
3. Ensure that the instrument is set up for “EXT CAL” (external calibration) as indicated at the bottom-right
of the display. If “INT CAL” (internal calibration) is displayed, press the ESC key to perform the
procedure in Section
3.1 Selecting Internal or External Calibration and set the Cal Type to External .
4. Insert probe tip into the Calibration Port of the external leak source.
5. The top number of the Calibration screen shows the “target” value (leak source rate), while the bottom
number shows the current “measured” value. Keep the probe tip inserted in the Calibration Port for the
duration of the calibration process, during which time the instrument performs a calibration at both a
high and low flow rate.
6. After the calibration cycle is complete, the new calibration data is saved and the display automatically
switches back to the Data Display screen. Note, however, if the PCHK Mode is set to AUTO (refer to
Section
2.4.7 PCHK Mode ), then a pressure check is performed prior to the display of the Data Display
screen.
NOTE: After calibration the instrument is automatically placed into its Search mode.
3.4 CAL Factor
The factory default CAL Factor of 1.000 will provide the level of accuracy as stated in Section 6 Troubleshooting
for all gases.
The CAL Factor can be changed for the following two reasons:

Allow the instrument’s internal leak source to be used to calibrate the instrument,
regardless of the gas being measured

Improve the accuracy of ppm measurements
Oz/yr
R134A
SETUP
SM SRCH
Oz/yr
R134A
SETUP
EXT CAL
0.00
0.89 TARGET
O/YR
R134A
MEASURED
O/YR
0.89
0.89
Oz/yr
R134A
SETUP
EXT CAL
TARGET
OZ/YR
R134A
MEASURED
OZ/YR