As part of my orientation, when I first started on a new job, one of the other maintenance technicians was assigned to show me around the plant. He shared an experience with me that I have never forgotten.

He showed me a float switch similar to the one in the picture above.

He said that one day he had to replace one those switches. He removed the old switch and installed the new one. He checked it out and it looked like it was sending the on and off signal to the PLC as it should. He went to leave but got a call on his radio from the control room saying that it was showing that the water level was high. He had checked and the water level wasn’t high. He pulled the switch out and checked the operation again. It looked like it was operating properly, and he put it back in. He did this several times before he discovered the problem. The float ball could be mounted 2 ways on the shaft and it was not mounted properly for the application that he was working on. If it was turned one way the float switch would be a normally open switch. When the float ball was removed from the shaft and re-installed the other way, it would be a normally closed switch. That float switch had markings on it indicating “NC” (normally closed) and “NO” (normally open) but they were very faint and not nearly as easy to see as those in the above illustration. He wasn’t familiar with that float switch and did not know that the float ball could be rotated to change the switch operation. That is why it took him a lot of time to figure out the problem.

I am confident that, because of that experience, he never made that mistake again. And, because he shared that experience with me, I never made that mistake.

This story was not important by itself.

To me, the most important part of this story was the realization that when we share experiences like this, it can be almost as effective as if we had the experience ourselves. And we can have the equivalent of many times our own experience.

That is what this blog is all about.