Digital Acquisition Unit (DAU)

The Digital Acquisition Unit (DAU) along with the Display Unit (DU) comprise a complete Integrated Avionics System (IAS). The DAU provides the interface between the aircraft sensor signals and the DU.

FEATURES

ARCHITECTURE: Two independent data acquisition channels.

CONFIGURATION: Single enclosure with four connectors.

ELECTRICAL: Interfaces with 28VDC aircraft power. EMI/RFI protection provided.

MAINTENANCE: Provides maintenance information on loss of input or processor. Built-in Test Equipment (BITE) for crew confidence testing and continuous in-flight monitoring.

ON-BOARD EXPERIENCE: Bell 412, Bell 427, Bell 430, Sikorsky S76, Canadair CL-415, CASA 212, CASA CN235, CASA C295, Zeppelin NT.

System Description

The DAU receives analog, digital (ARINC 429), and discrete signals from the various aircraft sensors and processes them in two independent channels. The DAU also provides excitation for various aircraft sensors. Each channel is comprised of a power supply, processor, and Input/Output (I/O) interfaces. Failure of either channel processor unit or its associated input circuitry will not affect the operational performance of the other channel.

The DAU provides output signals for the DUs (two to four), aircraft warnings and the aircraft Automatic Flight Control System (AFCS).

System Functions

The DAU conditions the input signals for the following aircraft system functions:

• Engine parameters
• Fuel Quantity System
• Hydraulic System
• Electrical System
• Caution and Warning messages
• OAT
• Mast Torque System (Helicopter Applications)
• Transmission System (Helicopter Applications)
• Audio and Visual Alarms
• FADEC interface capability