Last week’s blog spoke about reducing waste and downtime by implementing LEAN manufacturing procedures. This involves taking a proactive approach to improving efficiencies. This post will focus on selecting the right part for the job to reduce failure rates that lead to avoidable machine downtime and increased costs.
Hardly a day passes by where we are not contacted by a desperate end-user or equipment manufacturer seeking assistance with a situation of sensors failing at an unacceptably high rate. Once we get down to the root cause of the failures, in most cases it’s a situation where the sensors are being applied in a manner which all but guarantees premature failure.
Not all sensors are created equal. Some are intentionally designed for light-duty applications where the emphasis is more on economic cost rather than the ability to survive in rough service conditions. Other sensors are specifically designed to meet the challenges of specific application environments, and as a result may carry a higher initial price.
Some things to think about when choosing a sensor for a new application:
- What kind of environmental conditions will the sensor be exposed to? For example:
- Very low or very high temperatures
- Constant exposure to or immersion in liquid
- Continuous vibration
- Extreme shock
- Disruptive electrical noise (hand-held radios, welding fields, etc.)
- Chemical contamination
- Physical abuse or impact
- High pressure washdown procedures
- Exposure to outdoor conditions of UV sunlight, rain, ice, temperature swings, and condensing humidity
- Is it possible to relocate the sensor to move it away from the difficult condition?
- Is the sensor technology the best choice given the kind of application environment that it must operate in?
- Is there a way to protect the sensor from exposure to the worst of the damaging effects?
When you reach for a catalog or jump on the internet to look for a sensor, it’s a good practice to just stop a moment first and make a list of the environmental challenges that the sensor could face. Then you will be prepared to make an appropriate selection that best meets your expected application conditions.
Heavy metal parts being loaded into a welding cell can damage specialty nut detection sensors designed to stick through a hole in a part. Plunger probes are a better solution.
Unprotected and non-bunkered sensors in damage prone areas result in premature sensor failure.