MRK-D-0048 V4
Aeroqual Dust Sentry / AQS User Guide
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Check and adjust module flow rates
Table
Details to record
6
Monitor, customer, and calibration technician details
NOTE: It is important to have a high quality flow meter to perform these flow checks. See Figure 9 2.
Flow checks in this section are performed separately for each module. One or more modules can fail
the flow check, but others can pass. Calibration can continue on those modules which pass, modules
which fail can be removed and checked without affecting the calibration on the remaining modules.
6.1. Check all of the individual gas connections for any obvious leaks.
If a leak is found then correct it, go back to Step 5.9.
6.2
Perform a leak check on the sampling manifold.
If a leak is found then correct it, go back to Step 5.9.
6.3
Measure the individual flow rates, then add up the flows to equal total module flow. Record
the sum of the flows in the last column.
For each module, if the flow rate measured now equals the previously measured flow
rate (± 20 % LPM) then pass for that module, otherwise fail for that module.
If no specific module is causing a problem and all module flow rates are low then go
to 6.4 otherwise go to 6.6.
6.4
Adjust the flow rate using the bypass valve, circle yes if valve adjusted
6.5
Re-measure and record module flow rates for each module.
If the flow rate measured now equals the previously measured flow rate then pass.
Go to zero calibration.
For those modules which do not have the correct flow rate and cannot be corrected
with the bypass valve then perform a leak check or check for blockages.
If the problem can be corrected then correct it, otherwise replace the module. Go to
zero calibration.
If the problem cannot be resolved then remove the module and cap off the gas
connections. Record fail in the calibration report. Go to zero calibration.
NOTE: The total flow rate will be reduced because of the module which has been removed.
Zero Calibration
Table
Details to record
7
Zero calibration results
Zero calibration is performed simultaneously on all gas modules. One or more gas modules may fail a
criterion for calibration and others can pass completely. It is acceptable to fail a module but continue
with the zero calibration on the remaining modules, and to continue with a span calibration on those
modules which passed their zero calibration.
It is recommended to leave any failed modules running in the monitor throughout the zero and span
calibration process. After the calibration is complete on the remaining modules, then the door to the
monitor can be opened and the failed modules can be removed for inspection.
The order in which modules should be zero calibrated is:
1)
Ox,
2)
O3,
3)
PID NO2 does not have a zero or gain adjustment applied.
Use the AirCal 1000 to deliver zero air, connect the monitor to the AirCal 1000 with the tee open as
shown in Figure 5-6.
7.1.1.
Record the current offsets in Table 7, column 7.1.1. Start the zero air flowing. Make sure there is
excess flow out from the tee at the monitor inlet as shown in Figure 5-6 with the tee open.
7.2.2
Wait for the module to stabilise. This means the standard deviation is within the acceptable
range listed in Table 7. Column 7.2.3 (c).
If the values have not stabilised then write
fail
in the last column in Table 7 column 7.2.7 for
this module. Move on to next module and
go back to Step 7.2.1.
7.2.3
Record the stabilised reading in Table 7, column 7.2.3 from the 10 minute average.