PPCM Precision Pressure Controller-Monitor

The Precision Pressure Controller-Monitor (PPCM) is a calibration standard commonly used as a secondary or transfer pressure standard. The PPCM provides accurate testing of air data instrumentation. The operating software provides fast, error-free control of the operating pressures and it monitors internal functions to prevent damage to the unit under test. Vent and relief valves are also included within the unit to further protect the unit being tested.

With measurement technology similar to the TTU-205, the PPCM provides a stable, repeatable and reliable standard for pressure calibration with ease of use and remote control capability. This capability is provided through the IEEE-488 interface port located on the rear panel of the instrument. The PPCM can also be used to measure externally generated pressures. The PPCM operates in one of five modes:

Modes of Operation

• Dual Control – both channels control in respective units and are preselected by the user
• Altitude Control – only the Altitude channel is controlling, the Airspeed channel is disabled
• Airspeed Control – with the Altitude channel output ports uncapped, the Altitude Channel monitors local ambient pressure when Vc, Qc, or M is utilized as the reference for computation of Pt
• Then the Airspeed channel is controlled in terms of Pt, local ambient is utilized to prevent negative Qc conditions.
• Dual Monitor – both channels display the pressure at their respective ports.
• Reset – both channels are vented to ambient pressure. Should a failure occur the unit automatically reverts to this mode and vents the unit under test at a controlled rate.