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Always Keep an Open Mind

Overconfidence can result in mistaken assumptions

My name is Kazuo Akiyama, and I will be your "time-travelling" guide for today.

For professional people, having confidence in ones work is very important. However, confidence may also be described as a type of presumption. When you are overly confident, you tend to assume that your work (or your part of a project) contains no problems, and therefore that any issues must have been caused by others. It is all too common to well-meaningly involve all related parties when a problem arises, only to realize that you were in fact at fault and be forced to apologize. Therefore, while confidence is a necessary quality for professional people, this is a double-edged sword, as confidence can also be the cause of problems too. You need to be confident, but sometimes humility is important as well. In other words, as I will illustrate in this article, you should embark on any project with as few preconceptions as possible, that is, with an open mind.

This story concerns a client who was overly confident. Like last time, I will be taking you 30 years back in time.

A Sunday telephone call

It was my third summer with Kikusui. One Sunday, I was reading a manga in my room when the phone rang downstairs.
"It’s someone from your work", yelled my mother.

On the phone was the head of Kikusui’s quality control division, who had gone into the office on a Sunday to attend to unfinished work. He informed me that an OEM power supply we delivered a few weeks ago had malfunctioned, and that the client had asked us to fix the problem immediately as its shipping deadline was approaching. While the head of quality control initially discussed the matter with our service division, it was determined that because the power supply was from the first lot delivered, our service team would probably be unable to fix the issue, and that someone from product development should go instead. I had drawn the short straw.

I was told to fly to Oita prefecture, in Kyushu, the following day (I lived miles away in Kawasaki, Kanagawa), and that a member of our sales team would be waiting at the airport. My colleague then hung up.

We fast forward to my arrival on the client site the next day.

Power supply detective to the rescue

I was taken to a room containing an impressive looking rack onto which our power supply had been mounted. The power supply, which I had designed, was on the bottom of the rack, the middle of the rack contained a computer, and the top of the rack contained measuring equipment. According to the client, while the power supply worked sometimes, the supply of power would cut out intermittently. The client told me that he had tested all of the other components in the system and found them to be working normally, and therefore determined that the problem was caused by the power supply. He said that he had had called me in to determine the cause of the problem and fix it.

While the client was very polite on the surface, I sensed an unspoken aggression, as if he was saying, "it’s your job to put this right." I felt like a famous detective called to the scene of a crime. Once I had been briefed by the client on operating the computer, I went to work.

To get into the spirit and concentrate, I used my standard routine, in which I tell myself to "calm down and concentrate. Close your eyes and slowly open them again." Within no time at all, I had discovered the cause of the problem. I performed some repairs, and when I tested the device again, it worked fine. The two other racks in the room also functioned normally. I had travelled all the way to Kyushu for a job that took just 30 minutes!

"Danglers" were to blame

The issue was caused by a sliding shelf that supported the keyboard for the computer in the middle of the rack. A bundle of signal wires, including wires that carried signals to control the power supply, was getting caught in the shelf’s slide rail when the shelf was fully extended. I located a break in the insulation around one of the wires that had exposed the conductor inside. The insulation appeared to have broken after being jammed repeatedly in the slide rail. When the drawer was pulled out, the exposed wire came into contact with the rack, causing the voltage potential of the wire to drop to common ground. This caused the signals controlling the power supply to be interrupted. In other words, the power supply would turn off. However, when the sliding shelf was pulled only part of the way out, the wire did not short on the rack, and the power supply operated normally. Hence the intermittent nature of the fault.

Famed failure expert Yotaro Hatamura once said that cables, wires, pipes and other such accessories (which he referred to as "danglers") tended to be overlooked by engineers, because they are only positioned after the organization and structure of the device has been determined. That is exactly what happened in this case.

When I explained to the client what had happened, he was very embarrassed, and both he and his boss apologized profusely to me for making me travel so far to fix a problem that was their fault.

While I am prepared to travel if necessary when work is concerned, this experience was something else. It would have been a different story if the problem was Kikusui’s fault, but ultimately it was the client that caused the issue, so all I could do was tell them not to worry about it, and try and learn from my client’s mistake.

That night the client invited me to dinner, I guess to say thank you and apologize, the client took me to an excellent steak restaurant. They say that memories are more persistent when they are associated with aromas or tastes. Even now, on the rare occasion that I enjoy a delicious steak, I am reminded of this job.

TEXT BY
Kazuo Akiyama
Solutions Development Section, Solutions Development Department (Supervisor)

[Major achievements in product development]
PAK-T, PAK-A, PAD-LET series regulated DC power supplies
PAX and PBX series high-speed programmable power supplies
PFX40W-08 battery charging and discharging tester

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