Detection of electrical micro-breaks

Detection of electrical micro-breaks in the highly constrained circuits

Electrical circuits found in machine tools and in vehicles are subjected to significant vibration stresses that can affect the reliability and smooth operation in a circuit. Indeed, repeated movements can create discontinuities in the circuit. This phenomenon, called electrical micro-break, can cause serious malfunctions on complex circuits. It can erase memories or send wrong information to its receiver, and also cause electric arcs, oxidation and corrosion.

It is not uncommon to observe the effects of electrical micro-break on automotive multiplexed systems because they are particularly sensitive, or on rotating machines generating vibrations. The weak point is usually at the connector (plugs, sockets, slots, etc.) or at the slip rings (rotating electrical connectors).
The test methodology used, to highlight this type of fault, is to vibrate the subject at issue on an electrodynamic shaker, to electrically power the subject and to measure signals at very high frequency or the continuity of electrical connections.
This exercise is particularly difficult for the following reasons:

• The electrodynamic shaker generates an electromagnetic field that can disturb the measuring devices and cables.
• The vibration can damage the measuring means (sensors, etc.).
• It is sometimes necessary to perform measurements in extreme temperature
• The operation of the devices studied can be complex and requires sophisticated equipment to replicate the operating environment
• The frequency of acquisition and analysis are very high
• The detection limits are very low and require apparatuses with high acuity
• There are various signals to be measured (voltage, current, contact resistance, logic signal, etc.).
  

Today, we are able offer the industry a platform of reliable and versatile tests and characterizations of the electrical micro-breaks, and this is done by recording the smooth running of events and monitoring the contact resistance with a precision of detection to microsecond.

Industrial needs

Nowadays, electrical equipment manufacturers must guarantee the quality of their products in difficult vibration environments. Therefore, manufacturers are seeking for expertise in the accurate detection of electrical micro-breaks in conjunction with the know-how of vibrations.

They can describe their products and check their behavior in a perfectly controlled electrical environment. This is a step forward for the reliability of embedded and multiplexed systems.

It can also fulfill the need to understand and model the link between a dynamic excitation and an electrical continuity.
In addition, we can also provide means capable of reproducing defects found in an installation.