GE Druck ADTS 2 Series, Руководство пользователя

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Druck ADTS 2XX User Manual 40
K0451 Issue No. 1
3.7 Manual Venting of the Aircraft Pitot and Static Systems
Instrument Status on Power Failure
On removal of power, the main output valve linking external ports Ps1, Ps2 and Pt to the internal pressure
controllers will automatically close. The aircraft pitot and static systems remain safe but with the last applied
pressures now isolated and maintained in the hoses.
Instrument Status on Restoration of Power
When power is restored to the instrument the normal self test routine for the controllers will be performed and
at the end of this the controller will exactly equalize the internal manifold pressures to match those of the
external aircraft hoses and then the output valves will be reopened. This process will at all times protect the
aircraft pitot and static systems from adverse pressure transients, differentials or excessive rates.
When the output valves are fully opened, the normal parameter measurement screens become available
from the main menu and full control is again available. The testing may then either continue from the same
point (when the power failure occurred) or the aircraft pitot and static systems may be safely controlled back
to ground pressures.
Actions if power cannot be quickly restored
Two courses of action are possible at this point:
1 Leave the ADTS 2XX connected to the aircraft pitot and static systems with pipes safely isolated but
maintaining trapped pressures until such time as power can be restored.
2 Use the manual let-down valves on the instrument front panel to safely bleed the trapped hose
pressures back to ambient ground. This must be carried out in a way that ensures the Ps1 to Pt and
Ps1 to Ps2 differential pressures remain at zero while the whole connected system is brought to
ground pressure. The order of valve opening should be A then B to equalize, then C to vent to ground.
Ps1
Pt
Ps2
Atmosphere
C
A
B
XX
Let-down valves are precision
multi-turn, operated by small
slotted adjusters