What is wiring testing?

Concept of Testing & Inspection

It is commonly referred to as "continuity testing," "open-short testing," or "miswiring testing. They are synonymous with wiring harness and cable testing. Both types of testing involve testing for shorts, disconnections, miswires, and surplus circuits.


In general, the judgment of continuity of cables and wire harnesses is conducted in accordance with the item "4.5 Continuity" of JIS-C3005 "Testing Methods for Rubber and Plastic Insulated Wires".


"Apply a current to the conductor with a power source of 50 V or less and check the disconnection by a bell, buzzer, or other means."


Only the voltage of 50V or less is defined as an electrical specification. Resistance and current values to determine continuity are not specified.
The test methods for cables and wire harnesses are based on these and expanded to digital and analog circuits.


Resistance of conductors is specified in JIS-C3005, "4.4 Conductor Resistance.In the case of following it, the conductor resistance of the wire is tested by converting it to 1 km at 20°C (68°F).
It is not practical to apply this rule to mass production testing at cable and wire harness manufacturing.
This is because cables and wire harnesses often have different lengths of wires used in a single product and contain multiple types of wires.

It is also complicated how to subtract conductor resistance from testing jigs, and how to evaluate connector contact resistance.

Cable and wire harnesses are manufactured with wires and connectors guaranteed by their manufacturers. Therefore, there are cases where testing is applied for the purpose of testing the processed parts.



Conductor resistance is tested/measured according to the client's requirements.

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