Buck 1011C, Руководство по эксплуатации

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the aircraft skin usually works well. To achieve a different balance between inside and
outside temperatures, insulation and/or heat sinking can be applied as appropriate.
CAUTION--Make sure the sensor has adequate heat sinking when operating in hot
environments. Do not operate in environments over 60 °C (140 °F).
3.4 LEAK CHECK
(A)
If the optional aspirating kit is available, attach the aspirating fixture in place of the
sensor inlet fitting and temporarily seal the inlet holes. Take special care that the gasket is
properly oriented to allow free flow through the sensor body. Lower the pressure inside
the sensor as much as possible and check for leaks. The flowmeter ball should not move.
(B)
If the optional aspirating kit is not available, seal all ports of the inlet fitting, and
attach a pump and flowmeter to the pressure tap on the sensor body. Check for leaks as
above. (NOTE: To ensure a good seal, use Teflon pipe tape when replacing pressure port
plug.)
(C)
If a flowmeter is unavailable, the following alternate method can be used: Connect
the pump to the sensor by one of the above arrangements, along with a shutoff valve and a
pressure gauge. After pumping down the sensor, close the valve to seal it off, and observe
its recovery to ambient pressure. If recovery takes 10 seconds or longer, the sensor is
adequately sealed from leaks.
If a leak is apparent, locate is using positive pressure and a soap solution or equivalent.
3.5 PRESSURE WITHIN A SENSOR
The 1011C sensor should not be exposed to a pressure differential greater than 1.5
atmosphere across the sensor, as pressure in excess of this can destroy the seals. The
sensor is designed to be leak tight when the lower pressure is in the sensor chamber, i.e.,
pressurized cabin with the sensor chamber at atmosphere pressure.
3.6 CABLING
When cables are supplied with the 1011C and it is desired to use cables of different length
than the 3 foot (1m) lengths originally supplied, factory-made cables of different lengths
are available from Buck Research Instruments, LLC, on a special-order basis only.
Normally, only the connectors are supplied for the 1011C and it is the responsibility of the
end user to make cables. This is done because many agencies will not certify cables from
outside vendors, such as Buck Research Instruments, LLC, for use aboard their particular
aircraft.
Cable length can generally be varied without problem. However, the shielding and
grounding arrangement is critical, and the cable used should be identical to that originally
supplied or specified in Section 3.3 of the manual and in the wiring diagrams. If you have