An investment into calibration equipment and systems must be financially justified, just like any other business investment. But does a cheaper cost of purchase always mean a higher return on investment? Not necessarily. When building a business case for calibration calibration system investment, what may seem at the outset to be cheaper may not necessarily be so, if the evaluation is made from total or life cycle cost perspective instead of evaluating cost of purchase only.
We are sometimes asked if it is better to calibrate process instruments in the field, or in a calibration workshop. It is obviously impossible for us to give a correct generic answer for that question. The right answer for each application depends on various things. In this post I have listed a few common arguments for both field calibration and workshop calibration.
A HART transmitter is the most common smart transmitter type used in the process industry. What should be taken into account when calibrating and trimming a HART transmitter? Let’s take a look at the most important things to take into consideration. And also, let’s set straight the most common misconceptions regarding HART communicators.
Seismic velocity measurements provide ideal resolution at typical rotating equipment running speeds. Vibration is always transmitted through the bearings used on rotating equipment. It has been proven time and time again that measuring vibration on rotating equipment is the most universally effective predictive maintenance practice for critical pumps, motors, compressors, fans, cooling towers and rollers.
For example, over time, industrial motor bearings wear out and begin to wobble. Eventually these bearings will need to be replaced, or the machine will fail. But how do you measure the bearing performance to be sure you aren’t changing them out too soon, or in an even worse case, waiting until the machine breaks down and it’s too late? There is a whole world of 4-20 mA loop vibration sensors, like the Seismic Velocity 4-20 mA transmitter from Metrix or IMI Sensors, and they are gaining in popularity.
One of the questions we get asked frequently is how often a customer should calibrate his instruments. Unfortunately there is no straight answer to this, at least not one that would always be correct.
Instead there is a list of variables that should be taken into account when deciding the calibration period for any measurement device. Let’s take a quick look at these variables.
We quite often receive questions regarding the calibration of a square rooting pressure transmitter. That is why I want to discuss this matter shortly in this blog post. Most often the concern is that the calibration fails too easily at the zero point. There is a reason for that, so let’s find out what that is.
As many as every fourth company in the process industry is at the moment considering to make some kind of update to its calibration process and systems. I admit, the number sounds quite high, but it is based on a specific study we recently made with the International Society of Automation (www.isa.org) concerning calibration process changes.