Donaldson AFS-BH430-IBF-ICA, Instructions Manual

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AFS-BH430-IBF-ICA Aerospace Filtration Systems, Inc.
Revision: B Proprietary Information
Use or disclosure of this material is subject
39
AFS Bell 230 and 430 IBF
to the restrictions on the title page Instructions for Continued Airworthiness
d.
If the Cockpit Indicator does not illuminate, pull IBF circuit breaker. Run the altimeter test set
up to top of the range, check for continuity across the terminals of the Differential Pressure
Switch. If continuity is present, the Differential Pressure Switch function is acceptable and the
rest of the circuit is suspect. Upon completion of testing, ensure that aircraft electrical power is
OFF. Refer to Table 3.
WARNING
Applying a vacuum greater than 221 in-H
2
O (8 psi) may result in damaging the DP switch.
e.
This will functionally check both the differential pressure switch and the IBF “FILTER”
Cockpit Indicator.
Figure 4: Test Equipment Setup
Test Station Elevation (ft)
Test Method 0 2000 4000 6000 8000 10000
Low Pressure Calibrator
(inches of H
2
O)
11.0 ± 1.1
Altimeter Test Set
(ft above test station elevation)
760 ±80 ft 800 ±80 ft 850 ±90 ft 910 ±90 ft 970 ±100 ft 1030 ±100 ft
Altimeter or
Manometer
DP Switch
or FMA
Reservoir
Handheld
Vacuum
Pump