Dynamic Cut Through

One of the most common means for damage to a wire/cable on an aircraft is when the wire/cable is crushed. This may happen by a misaligned LRU, accidental contact by maintenance, or any other way that a wire/cable may be pinched when in-service. A wire/cable’s ability to withstand compression damage, particularly at elevated temperatures, will […] Read more

Dielectric Withstand Voltage

The dielectric withstand voltage (DWV), sometimes referred to as the “Voltage Proof Test” or “Wet Dielectric Test”, is perhaps one of the most referenced tests when examining wires. The reason is that the test performs the most important part in wire insulation assessment: it determines if the wire insulation is free of breaches (or has […] Read more

Forced Hydrolysis

The forced hydrolysis test places the wire/cable specimen in a high-temperature water bath for an extended duration to evaluate the durability of a wire insulation in high-humidity conditions. Depending on the particular wire specification needs, the test may be required to run for thousands of hours. After the prolonged exposure, the sample is then examined […] Read more

Blocking

This test evaluates if a finished wire/cable specimen will block (stick to itself) when subjected to the specimen’s rated temperature. While on an aircraft, wires may be exposed to high temperatures and it is important to check if the finished wire specimens are prone to blocking (in other words, the test examines whether the wire […] Read more

Overload Resistance – Smoke Resistance

In short circuit conditions, a circuit may run over the designated current for an extended duration before the circuit protection is activated. During this time, a wire/cable may become very hot and potentially exceed its designated thermal rating. Well designed wires/cables will not release any smoke during this fault condition. The overload resistance test, also […] Read more

Capacitance per Unit Length

Sometimes referred to as the Dielectric Constant, the capacitance of a wire/cable is of particular interest for data applications (limited importance for power applications). Those wires/cables with high capacitance values can significantly impact signal quality, particularly high speed data applications. This test, which can be performed on a wire or cable, measures the specimen’s capacitance […] Read more

Conductor Diameter

Also referred to as the wire size test, this evaluation measures the sample’s conductor diameter after the insulation has been removed. This test method is important for identifying the proper amount of conductor used for a particular gauge. Verifying that the supplied wire has not been misrepresented. The test report includes the measured conductor diameter […] Read more

Conductor Resistance

This test determines a conductor’s direct current (DC) resistance at a specified reference temperature (typically set at ambient temperature). There are two methods used to conduct this test known as the Kelvin Bridge Method and the Wheatstone Bridge Method, which are used to obtain the resistance of the specimen. Both methods will give similar results, […] Read more

Cable to Cable Abrasion

This test is used to determine the ability of a sample’s insulation to withstand the rubbing on a similar sample in a vibrational environment. Wires/cables in close contact with one another can rub against each other causing progressive deterioration of the insulation. The impact of how quickly the insulation degrades in a wire-to-wire scenario is […] Read more

Scrape Abrasion

One of the most common means for wire failure is through insulation chafing. In operating conditions, wires/cables are exposed to various sharp edges on aircraft that can quickly deteriorate the insulation integrity. This test assesses the wire/cable’s insulation durability to sharp edges at ambient temperature. The sample is abraded until failure. The failure is identified […] Read more

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