"Relays, Diodes and learning how they work"

During the second week of instruction my instructor began to bring up relays and diodes. I remembered a lot about these things from a couple of previous electrical courses but just like everything else if I'm not using it or studying it it tends to go to the back of my brain. Needless to say I had some relearning to do. My instructor gave some really good lectures on relays and and what they are used for and also how they work. During our lab time while working on our relay test boards he also came over and began talking about diodes and what they are. He then showed me and several other students how to test a diode using a multimeter. Along with the class discussions and conversation with my peers, There were a couple of videos on you tube that helped my understand how diodes and resistors work.

 Below are pictures of me testing a diode using a multimeter and in this case on this test board there was an open diode.

Here are a couple links to some of the videos that helped my understand what was really going on inside a diode and a resistor.
www.youtube.com/watch?v=DUiNq7P...
www.youtube.com/watch?v=JBtEckh3L9Q‎

Here is another link to how light emitting diodes work.
www.youtube.com/watch?v=8quZrUcRFlw‎‎


This last week I also had the task of continuing to test switch boards, this time the boards had relays on them. What we were looking for on the boards was open circuits, high resistant voltage drops and shorts. I found this to be difficult at times and pretty straight forward others. It was another one of those things where I had to keep track of the steps I was taking and make sure I was going in the right order. When I did that things worked out fine. Below are some picture of some of the testing I was doing.

 In the pictures above I found an open circuit on the + side of the circuit. this was just one of many boards tested.

I think the thing I can reflect the most on the most over this last week was some of the discussions I had with some of my peers while working on test boards. I would here someone say "oh it's a bad relay on this one" and for some reason several times I asked different people that would say this, "well why is it bad?". This would prompt a discussion. This is when I feel that my understanding of relays and diodes and how to test them came to help me understand more about them while hopefully helping someone else with the same. It seems to me if some thing is broken I can probably fix it but I  also feel I have an obligation to try and figure out why it broke or isn't working. WHY, WHY, WHY

Week 2
Hours19ish