Aerospace wiring tester

Citation

(2006), "Aerospace wiring tester", Aircraft Engineering and Aerospace Technology, Vol. 78 No. 2. https://doi.org/10.1108/aeat.2006.12778bad.012

Aerospace wiring tester

Equipment

Aerospace wiring tester

Keywords: Aircraft, Test equipment, Wires

Aircraft wiring is at constant risk from damage through vibration or moisture ingress, but the complex nature of avionic wiring looms and the confined spaces in which they run often make the location of faults extremely difficult. The new Advanced Systems Tester 900AST from 3 M is said to be the first, handheld, integrated unit that has been designed to locate all types of open circuit, short circuit and intermittent faults in the wiring classes used on most military, commercial and private aircraft.

The 900AST can be used to quickly locate faults and verify repairs using its resistive fault location (RFL) and time domain reflectometer (TDR) functions. The unit also provides a wide range of other tests to categorise and locate particular problems.

TDR operates by sending a pulsed signal down the line under test. A fault on the line will result in an echo being sent back from the fault site to the test instrument. By measuring the time taken for the echo to return, the location of the fault can be determined. RFL is used with problems, such as ground faults, which are not easily located using TDR. RFL works by measuring resistance at various points in the conductors under test and using these measurements, together with data on the size and material of the conductor, to ascertain the position of the fault.

Uniquely for a handheld tester of this type, the 900AST can also conduct soak tests: extended period resistance measurements that are particularly useful in the identification and location of faults caused by moisture or corrosion.

Despite its sophistication, the 900AST is said to be particularly easy to use. The unit's large 192×192 pixel black and white display allows clear presentation of test results in a graphical, icon-based format, while the built-in infra red port allows stored data to be uploaded to a PC for further analysis. The simple, menu-based user interface includes internal help screens making operation quick and straightforward.

“Our new 900AST gives aviation mechanics a comprehensive battery of tests to help them locate faults in a timely and accurate manner”, explains Neil Stansfield, key Account Manager at 3 M. “Quicker fault finding minimises repair duration and means expensive aircraft spend less time on the ground. This system is typical of the ways 3 M is innovating to solve real industry issues.”

The 900AST is a compact unit weighing only 1.8 kg including batteries, test leads and case. It is ruggedly constructed to resist moisture ingress and can withstand a 1.5 m drop onto concrete. Six AA sized alkaline cells will power the unit for 22 h of typical use.

Details available from: 3 M UK. Tel: +44 (0)161 237 6174.