Many environments are not ideal for precision servo electronics and automation components. Industries such as: Automotive, wood working, plastic plants, water treatment or water associated facilities, and many more, contain small particles of grease, oil, dust, moisture, and all other particulates in the air and surrounding areas. These particles are contaminates and will find their way into your drive.
Most cooling systems are broad systems within the drives. A fan(s) will be blowing the hot air off of the driver circuits and boards in a broad fashion. As the fans blow, the contaminants are blown across all the critical areas of the drive.
Many contaminants become conductive over time, some corrosive enough to eat through the boards protective/conformal coating, and the boards themselves. Some cooling systems are a little better at keeping contaminants away from the boards and electronics. By directing the air through a shroud to the heat sink it keeps contaminants from building up on the boards themselves, extending the life of the drive. Over time the heat sink does get build up, preventing the dissipation of heat from the high current components. Extensive heat build up without relief, will lead to a shorter lifespan of the drive. Fan bearings will also deteriorate due to contaminants in the air, essentially leading to drive failure.
Anything mechanical with moving parts will eventually go bad, add contaminates to the air and it greatly reduces the lifespan. To extend the life of the drive, we recommend cleaning the drives on an annual basis, if not sooner, replacing fans, and keeping heat sink passages clear of contamination or any kind of debris. We also recommend you have adequate cabinet cooling systems, are regularly replacing the filters, and keeping up on any maintenance issues as they arise. This type of maintenance is essential in prolonging the life of your drive, ignoring them will typically lead to much more expensive repairs in the long run.
What is the technique for finding bad components on a drive board?
A variety of techniques are used to determine if a component is bad. We have a wide range of test equipment including our DMM’s (Digital Multi-Meter’s), Huntrons, Test fixtures (typically designed in house to test certain components and circuits, Drive/Manufacturer Specific), capacitor and coil checkers, and of course the most useful tool of all, our eyes.
Multi-meters determine if components are out of tolerance, such as resistor values or capacitor values changing.
Huntrons check for individual components, groupings of components, a full circuit, to see if we have a good signature of the component that corresponds to a known good signature in our data base from a good working board, and checks the response making sure it doesn’t break down when the voltage and frequency are applied.
There are many fixtures for testing driver boards, before powering up, to ensure safety and to avoid causing catastrophic damage to the boards, if the IGBT’s don’t fire correctly.