Two weeks ago, I just got a job from my supervisor, to fix a measurement system, which was initially designed by someone else from electronic engineering school. The system, consists of a very complicated electronic circuit, operated by the LabView, which was again programmed by another electronic engineer. National Instrument was used as the ‘agent’ that send the command from the LabView, to the electronic circuit, to bias the samples on the test plate. The samples are transistors.
The system wasn’t failed, it was “disintegrated” or disconnected. The circuit was not connected properly, and it was unused for 5 years. My mission was to setup the circuit again, based on a full-of-electronic-term-document available, and my very less understanding about electronic. Together with me, an intern from electronic engineering school, were assigned with this mission. He is more experienced in LabView programming, so I left him doing the software, and I and my supervisor to take care of the hardware part.
Understand from the most fundamental
I had totally no idea initially with what’s going to be used with the measurement system. I had to study and study over the documents, and read and refer to sources online, to find and check a lot of vocabularies and jargon, in order to understand what it is. After understanding how the system is going to be used, I started to understand how should the circuit be connected.
In Physics, I learn electronic too, the very basic one – voltmeter is connected in parallel, multimeter is connected in series. Positive to negative, plus to minus, to form a loop, in order to let the current flows. That’s all I know. I start using this most general rule from the beginning.
A schematic diagram was available in the document, and it took me 2 days to understand it by a little bit. There were more information in the document, including the mechanical structure of the PCB board, the circuit designed on the PCB board, the connection of each of the sockets, 15 pins or 62 pins, high power relay, jumping switch, etc etc…But, there was no such thing like “This connect to that port, that connect to this terminal, turn the switch on and run.”
It’s a stranger for me. I don’t know it, it doesn’t know me. I start understanding it by reading through the document, analyse the circuit flow on the PCB board (which is crazy for engineer I think).
Start to connect, but failed
When I started to connect the circuit, and ran the system, no result was given. There should be certain current, but all of them shows zero. As what I learn from Physics, circuit must be closed. Yes, I checked, and found out that it’s not closed! How to make it closed? I got no idea, and keep reading back the document again.
“Oh ya, there’s one more terminal, which was not connected back. That’s why, no current flow. That’s it, alright. Hmm..Let’s try.” That was this Wednesday, after one week and half, I told my supervisor, I would like to try the one last thing, to connect the terminal back to form a close loop. If that doesn’t work, it’s end of my brain capacity already.
Then, connect, and it works! But…
Thursday morning, we went to the lab, and tried to connect the one last thing. It worked! Finally! My mind was so surprised with the result that I saw. The current was measured! Yes, there’s reading from the system. Bingo!
But, there’s another problem again. (No point discuss here, but there was a problem). I spent another half day again, to think over and over again. I was thinking about it during my lunch, read back the document once after my lunch, again and again. Until my supervisor sat down beside me, and started discussing about it. We couldn’t find out anything from the document, until we went back to the lab again and test something very simple: Just to turn the jumping switch, then it works. What a crap…
The last thing I had done, was to turn the jumping switch to another side, then the system is up, problem solved!
What I have failed, what I have gained
Throughout the entire fixing process, I failed some things:
I failed many times for letting the program to run, and from there I learned more about LabView. I started to revise LabView and read the codes from the people.
I failed to make the current flows since the first time, and it proved many of my logics correct since beginning, when I was thinking the logic in that way and I didn’t implement it directly. I didn’t make it a closed loop. From there, I learned how to build up a circuit, and I’m more familiar with the electronic circuit now.
I burned two fuses, from which I learned that I shouldn’t short the circuit, which causes the overcurrent flows through the fuses and burn it.
Now, I am more familiar with measuring the current, measuring the voltage, grounding the terminal, providing the potential difference, closing the circuit, controlling the relays using program, and many more. It’s not easy, but it was stressed. But, whenever I completed one tiny thing, it was a fun. When I completely fix the whole system, I felt the success.
I was so time limited, as I was leaving the company as a part-timer for three weeks, and going back as a full-time staff soon. I completed this task just one day before I left. How lucky…but, I paid a lot effort, tiring yet fun.