Getting lazy to update this blog daily..but its not compulsory anyway so no harm done. Ok lets start off with activities I did yesterday morning. Me and Mr. James went to deliver some items to two big factories in Petaling Jaya. Both factories are actually the main manufacturing plants of a famous food and body care products in the market! But we did not went into the manufacturing plant. Just at the technician's room to deliver the items. Security is tight! The security guard at the first factory is not friendly at all! He even scolded me for not wearing safety shoes! But he's just doing his job. No hard feelings.

Went back to the office after lunch and soon after I was given an inverter and asked to connect its transistor output terminal to a relay. Then he asked me to connect another relay that is used to run the inverter by connecting it to the inverter switch. The setup is shown below.

This is actually to simulate the problem we encountered in the Cheras labeling factory I went into last week. The PSU is to simulate the state of a PLC signal (on or off). Not much problem encountered and I managed to connect all the relays and the PSU and get it to work just like how Mr. James wants.

Enough for yesterday. In the morning today Mr. James went out so I got almost nothing to do in the office. Then at around 11.30am Mr. James asked me to go to a rubber factory to assist one of his technician to solve a DC drive related problem in the factory. Its the same rubber factory I went into on Day 1 of my blog. 

The DC drive is actually similar to an inverter but it outputs DC voltage to run a motor. The problem is the motor is not running when it is powered up. This is due to a fault on the rotary encoder connected to the drive. The technician opened the encoder cable casing and found that one of the wire in it has been disconnected! So I soldered the wire and then the factory technician took over and plugged in the cable casing into the encoder. The machine is powered up and the motor is running! For a minute there I thought that the problem was solved and I could go back early but to my dismay, when the factory technician turned on a switch, the motor at the end of it did not run!

Mr. James technician tried his best to solve this problem but was unable to do so because the instruction manual for the DC drive is not available. He will come revisit this problem tomorrow morning with me. Went back at 5.30pm from Shah Alam and traffic was already abnormal. Quite a stressful day today. I was standing for hours observing the technician! 

No office work today so this is going to be short. Went out almost 90% of the working hour today.

Something peculiar happened in the morning. BLACKOUT!! Even the restaurant where I had breakfast nearby was affected! According to the neighbor, the blackout started since 12.30am last night! We are helpless without electricity! No internet, no fax, no light and no air-con! Lucky the phone was working. I was lost and don't know what to do because I can't power up anything! Now I realize why big big factories suffer HUGE profit losses because of no electricity. Was at the office until 10.30am but the electricity still did not recover. I wonder what had happened at the substation..

Feeling unproductive, we went out to the Sungai Besi factory to install the photo sensor I mentioned yesterday and to solve that inverter dilemma once and for all. Mr. Alex was there when we arrived at the factory. His task is to install the two sets of photo sensor and I was asked to concentrate on the inverter problem. Recall that the inverter is unable to deactivate when the switch at the inverter is in "OFF" state. The proposed solution was to bypass a relay that connects the switch with another brand new relay to isolate the signals coming from the PLC.

Mr. Alex had taught me how to connect the relay and in fact I have tested his teachings on Day 28 of my blog. Diligently wired the relays inside that dust-infested control panel. Fortunately for me, there was no cockroach in there or otherwise I would freak out and embarrass myself in front of the workers! Occasionally doubted my understanding but Mr. James came and enlightened me with the answers. Did a tiny mistake but later Mr. Alex came and fixed it.

Turned on the big machine to test the new solution. I was very anxious worrying that it might not work. About one minute after the machine runs, its time for the inverter of interest to run and test the new solution. Amazingly it worked! The motor runs and stops when it is supposed to! Problem solved! What a relief! I can sleep well now..

Went to Old Town Kopitiam in Puchong for a drink. This time Mr. James INSISTED that I order a meal. Wow, Thanks Mr. James!!

Still waiting for the visiting lecturer to visit me. Mr. James say that he still did not receive any calls from UNITEN. I just hope that this is not going to be a surprise visit because like I said before, me and Mr. James are like, "macam biskut chipsmore, kejap-kejap ada kejap-kejap tinggal habuk je.." On the other hand, its almost three weeks since my collie left the company. Still waiting for a new collie to assist me in my fieldwork and to fill that loneliness void in me. There's nothing I can do but to wait for both events to occur. The wait is sometimes mentally painful.

Week number SEVEN! Here we go! Hey, wake up! Its 6.30am! Go and iron your clothes NOW! That tiny voice inside my head won't stop bothering me until I get off that bed! Half awaken, went to the cupboard and took a set of attire and went to the ironing board. Sometimes life feels like a big computer program. The 5 senses act like an input device while the hands and legs outputs the preprogrammed tasks. The brain is obviously the central processing unit. Can somebody come and program my brain to be like Mr. Einstein?

Alright, enough with the nonsense. Today has got nothing to do with inverters, AGAIN! No fieldwork today, just another day in the office. But tomorrow I will definitely go out, according to Mr. James. In the morning I did some filing work, then Mr. James gave me a set of gadgets consists of a switching PSU, weird-looking rotary encoder and its best friend, the counter. Whenever you see a rotary encoder, there's definitely a counter connected to it. Supposedly, when the rotary encoder rotates one unit, the counter will count one unit and resets when it reaches a certain preset value. I may have discussed this on the early days of my blog post. The setup is shown below:

What a funny looking encoder! At first glimpse one may think this is the code-manipulator-thingy of a safe! In fact, it looks just like one! But beware, your eyes can fool you! Ok back to the story. The reason why the switching PSU is needed is because the encoder can only accept 5VDC as input unlike its best friend which can consume the household 230VAC like a hungry beast! In short, when everything is connected properly, the counter will reset when the encoder completes one revolution. 

After lunch Mr. James asked me to play around with the Panasonic PLC. He asked me to program the PLC to control some input device and outputs to a relay. Before he went out, he asked me to connect the photoelectric switch and the relay to the PLC. With the help and guidance of Mr. James I managed to connect them and start work on the programming. The setup is shown below:

Initially I only used a single switch and relay to simplify my program and to start learning slowly. Mr. James went out at 2.30pm so I have until 5.30pm to experiment with the ladder diagram and the PLC. Again I would like to stress out that PLC programming is totally different than PIC18 programming. There's no "code" for a specific task, only "symbols" that can be either ON of OFF. Not to mention the limited types of symbols a ladder diagram can have (sometimes less than 10 symbols) unlike the 77 instructions of a PIC18. For beginners, its tougher than the MicroP subject! But I slowly learn and managed to do a simple input-output program that works.

Went back at 5.25pm today. Traffic was amazing! The journey back took a record-breaking 35 minutes! Normally the drive back took about 50 to 75 minutes. Maybe because coincidentally most of the traffic lights are green along Persiaran Kewajipan. If only life is that easy.. 

Yesterday and Monday was the most tiring and stressful days of my internship so far. But the "rain" has to stop eventually and up comes the sunshine. 

There's NO fieldwork today so not much movement and thinking is involved. But still, I have plenty of work to do in the office like soldering the potentiometer, test the customer's voltage regulator device, reorganize the toolbox and ponder about yesterday's Sungai Besi factory problem. Initially we plan to revisit the factory for the third time today but since there's some conveyor problem at the factory, we cannot go there until next week.

In the morning...aaarrggghhh!! I can't recall what I did this morning!! Should have written it down! Lucky I took a picture of a machine. The machine is actually a motor and an inverter bundled together in one package. It was sent to us because the inverter was damaged by some fluid that has entered into the inverter and short-circuited the circuitry inside. The motor is fine so only the inverter is replaced with the exact same model. Below is the picture of the whole machine.

Wired the power cables, motor cables and mounted the inverter onto the base of the motor. After everything is tight, I powered up the motor and inverter for a short test run with the supervision of Mr. James. We only change one program code of the inverter according to the instructions in the motor manual. Everything is running fine so I switched off the machine and prep the machine so that it is ready to be collected by the customer.

After lunch me and Mr. James pondered about the Sungai Besi factory problem. Recall that the problem is that the inverter controlling a motor is unable to deactivate itself after all of the switches on it is turned off. The off signal is coming from an array of relays and a PLC module. Mr. James gave me a similar inverter to simulate the problem. He thinks that the problem lies somewhere in the wiring or relay of the control panel back at the factory so he suggests that I isolate the switch signals with a relay. Great, how do I connect them? I took the challenge and Mr. James gave me some time for me to figure out the terminal connections.

After a few tries, I managed to find the correct terminal connections. And I learn how a relay works too! Now the signal from the control box has to go through the relay before reaching the switch terminals on the inverter. If the switch is on, it will activate the relay and the relay contact will then pass the signal to the inverter thus activating it. This is how the terminal connection looks like:

The "rain" of work have finally ceased, for now. Not sure what's in store for me tomorrow but I better prepare myself and get sufficient rest while I can. The rain can re-start at any moment and the next one can be worst than the previous one

This post was supposed to be published yesterday. I was unable to get it done because I was too tired to articulate any words. No fieldwork yesterday. Mr. James asked us to explore the use of some special function terminals of the INVT inverter and connect them in parallel with a pilot lamp and a relay. The setup is shown below:

The output of the special function output terminal (HDO Terminal) is supposed to output a 24V DC when it is activated. However, when we measure it, the voltage is less then 20V and it is unable to activate the relay. By the way, that relay is activated or energized when it receives a 24V DC voltage. Can hear a "clip" sound when it's on. After a while troubleshooting the problem, we abandoned the problem and went for lunch.

Around 3.30pm, a customer walked in. He brought with him an inverter and a very speedy motor. The rated speed of the motor is 24000rpm! That's more than twice faster than the fastest hard drive available on the market! Very speedy indeed. And very scary to work on too. Even at half the speed the sound is like the motor is going to explode any minute! 

The motor is cylindrical. Its about the length of an A4 paper and its very heavy. I can barely carry it with my arms! And another interesting feature of the motor is that it has an internal watercooling system! Unfortunately we were unable to simulate the watercooling feature. Sorry I couldn't snap any picture of the motor because the customer was there. I hope I have described enough.

Obviously the customer did not simply walk into the office to show-off his powerful motor. He came with a problem in mind and we, have the solution (Yeah, right!). He wants us to setup the inverter to control the motor and teach him how to setup and program the inverter. Piece of cake! Not until we stumbled on a big problem. During acceleration, the current shoots up too high and the inverter trips when we set the acceleration time to be less than 1.5 minute! But the customer wants it running at full speed in 20 seconds!  That's impossible! After explaining to the customer the situation he finally agreed on the issue.

Unsolvable problem that was. Can't blame the inverter because its one of the high-end inverter and it is Made in Japan. 

I don't know why I was so tired yesterday eventhough there was no fieldwork. Slept early at 10.30pm yesterday.

   

Yes, thank you Captain Obvious! Of course two brains are better than one lonely brain! Today my collie didn't show up for work! I was quite lonely today..huhu..well not for long. Today is full of meaningful activities. Started off the day by learning a new component. The "Pilot Lamp". The pilot lamp is normally used to indicate if there's any fault in the machine. Its like an LED on steroids because it uses either 24VDC or 240VAC to power it. In my case it is used to see the state of the output of the SSR. I connected them to the output of the solid-state relay (SSR). Remember I mentioned about SSR last week? Below is how the SSR looks like. At the end of this assignment I learnt how to connect the pilot lamp. The connection is shown below. Its not clearly visible though.

Today Mr. James brought me around Shah Alam and Petaling Jaya to deliver some stuffs to the customer. Then we went to Giant Hypermarket near UNITAR. Guess what? Mr. James "belanja" me KFC at the hypermarket! Wow what a great employer! Thanks a lot Mr. James!!

Then we revisited the food factory in Shah Alam again to look at the counter. Its the same machine that I described on Day 8. Apparently the relay mechanism under the table that controls the motor and the relays are not synchronized with the other two relay mechanism. I managed to set the counter such that the open-close-open-close rate of the clamper is synchronized with the other two clampers but somehow the relays that controls the motor and something else under the table had a different on-off pattern than the rest. Quite a stressful moment I would say because I was given a time limit by Mr. James and I fail to solve the problem. But its all part of the challenge of being an engineer. Feels great to have experienced such a situation.

Then we went to an LED and semiconductor manufacturing factory to inspect their UPS system. Too bad the UPS system is outside of the factory, away from the manufacturing plant. I wish to see the doping process of a semiconductor and how to fabricate the LED. Ok back to the story. The UPS is used to control the factory's compressors. There are so many compressors around all the size of a car! I wonder why they need such a big compressor. At the control panel I saw BIG and THICK wires! Its the thickness of the rope used in "tarik tali" competitions. It is used to carry a whopping 1200 Amps of current! Those amps not only kill, it will fry the unlucky fellow in moments!

The compressors are located in an isolated room outside of the manufacturing plant. Its very noisy and hot inside the room with all that compressors heating up and the high level of noise they generate. Truly an uncomfortable place to work at. Lucky I was in the room for a short period of time. Once the UPS is wired, the compressor (the one controlled by the UPS) is powered up. The sound of the compressor powering up is melodious. Its like a Lamborghini engine being powered up but the noise is a lot louder and lasts longer. Very nice melody.

Today I saw two UNITEN students on the road! One in LDP near the big Western Digital Factory. I can't recall the guy's name but he's driving a black saga aeroback plate number WHP3090. He looks quite stressed maybe because the highway was jam-packed at that time. The other one on my way back home at Kewajipan intersection. I don't know this guy but I always see his car in UNITEN. He's driving a green satria plate number MAM 11. I know this car because of the plate number. Very unique.

The week's over! Time to rest. But I feel like going out tomorrow. Maybe to OneUtama or The Curve just to look around and buy some stuffs. Its been a while since the last time I went shopping.. Yes you read correctly. Shopping. Women are not the only ones holding many shopping bags in the Megamall you know!

Thursday already? I still felt like Tuesday! Still have that "Monday Blues" kind of feeling. What makes me nervous in this internship is that I don't know what to expect whether there will be any fieldwork today, what kind of assignments Mr. James will give me today, what to eat for lunch..everything is unpredictable. Its not a routine. Totally different from lecture week. The timetable is fixed, lunch hour is fixed, even sleep time is fixed. Its quite a challenge to change this routine-based mindset. But its a good thing actually as engineers have to work on odd hours and often given weird assignments.

In the morning I did some troubleshooting to the inverter. But today I learnt something new about RELAYS. This type of relay has four "contacts". I think I have discussed this somewhere in my blog. But this time I learnt how to use them to access specific functions of the inverter. Each relay has two types of contacts, the "normally close" and "normally open" contacts. To access a specific function in an inverter when the inverter is powered on, connect the "normally open" contact so that when the relay receives power, the contact moves to the "normally close" contact and turns on the feature that is accessed by the relay. You may not understand this but nevermind. I'm just recalling what I learnt this morning. The relay that I used looks very close to this:

In the process of learning that, I discovered that I have made many silly mistakes before. Remember the drawing I did yesterday? There's a mistake in one of the measurements. Then I discovered I copied something wrongly, and did not learn some important things from my collie. When asked a simple question from Mr. James, I answered wrongly. 

Mistakes, humans are prone to it. I realized that when you have made a mistake and say to your boss "But Sir, everyone make mistakes...", you can get fired! Yes we all make mistakes but the question is, "How often you make them?". Mistakes can be costly to the company. It can humiliate you as well. I seriously hope that I will not damage any inverters or other expensive components due to improper or incorrect wiring. 

After lunch Mr. James brought us "jalan-jalan" around Puchong, Bukit Jalil and the outskirts of Shah Alam to deliver some stuffs to the customer. Before the trip ends, we revisited the rubber manufacturing factory in Shah Alam to inspect a faulty inverter and a set of proximity sensor. I have visited this factory before on Day 1 of my diary. There I saw a motor about the size of a Perodua Kancil. Its huge! I wonder how much power is needed to run it! There's also a gear system attached to it.

That's it for today. Went back at 6pm and it was raining. The statement "asal hujan je KL mesti jam" in Day 7 of my blog is true! The trip back took longer than usual, about 1 hour 10 minutes!

There, I said it! I am still so far away from being even the basic engineer. Me and my collie spent most of the day installing an inverter in a furniture factory in Kepong but this time, WE are the technicians. Today's visit gives me the REAL experience of being an enginner.

As soon as we arrived at the factory, I was asked to read the circuit diagram of a relay. This relay has 14 pins and 4 relays built into a package with three pins each. The two other pins are supposed to be connected to a power supply. It is then mounted to a connector box to ease the wiring process. The relay and connector box looks something like this:

Then Mr. James asked me to connect the power supply input and one of the relay input. Oops..which wire to connect and where to connect them? Feels kind of embarrassed not to know such a basic thing. My collie is way ahead doing some soldering work. Mr. James then guided me on what to do. Ooo so that's how it is! 

Next we move on to installing the inverter to a machine to upgrade the motor speed control. The inverter used this time is different than yesterday. The programming method is different. Did some drilling work and lots of wire stripping work. By the time I was done it was 1.30pm and we went for lunch nearby. Again Mr. James was paying for my nasi campur. (Thanks a lot Mr. James!)

What a great lunch! Ok now get back to work! I wanted to connect my stripped wire to the inverter terminals but Mr. James stopped me from doing that. I'm suppose to clamp the wire first. I never knew such procedure existed. Here's the brief conversation between me and Mr. James:

Such a basic thing and I never knew about it! There's a lot that I don't know! Thank you Mr. James for patiently teaching me! There's some other tasks that Mr. James told me to do but I don't know where to start. Somehow I feel that I'm not being very helpful today. As an engineer, we must know exactly what our superior wants and MUST be able to know what and how to do it flawlessly. This is what I learnt today. 

Went back a bit late today. Still a long way to become a competent engineer. I hope I can keep up.