Its never too late to learn something new. Today I learn two new devices. The FP0 PLC and the DIN rail power supply. First up, the Panasonic FP0 PLC. Around 9.30am Mr. James gave me the PLC, a connector, the serial cable and a power supply and asked me to test the PLC. This is the smallest PLC I've come across so far. Its kinda cute too. Alright the picture:

The small green box is the PLC. Just in case you can't spot it. The PLC is powered by a 24V DC unlike the normal bulky PLCs that consumes the household 230V AC supply. To program it, the user needs the FPWIN GR software. The interface is shown on the laptop. Its a simple PLC meant for basic applications. The software is quite easy to use. Programming is quite easy even for a newbie like me.

Few minutes later two customers came in to purchase the PLC and the serial cable. He also brought with him his laptop to install the programming software and test the PLC. They went back as soon as they were satisfied with it.

Oh, I forgot to mention one event that happened before the PLC customers walked in. A chinese lad came to purchase a black Sanken inverter. He said that he will connect the inverter to a switch to run a motor and a potentiometer to control the speed. He wants us to demonstrate how to do that so we unpacked the inverter and connected it to the control box and the potentiometer. Then I taught him how to program the inverter. Feels good to be a teacher! 

Ok, the next new device. The DIN Rail power supply. This power supply outputs 24VDC and needs 230VAC to operate. Just like the normal switching power supply I have posted few days back. This PSU is specifically designed to be mounted inside a control box on the DIN Rail. The DIN Rail is a long metal plate that is used to mount relays, PLCs and power supplies. Imagine a cloth hanger. The DIN Rail is the hanger and all the relays, PLCs are the clothes. 

Initially the output was 24-point-something volts but I adjusted it to be precisely 24.00Volts by adjusting the potentiometer at the PSU. Here's the picture of that PSU:

That's it for today's activity. No fieldwork so we stayed at the office after lunch. Tomorrow is going to be either a great success or a complete failure. I don't know what to expect tomorrow because I'm not familiar with the device that we will install there. Mr. James asked us to be at the rendezvous point near the office and we will convoy with another group of people to the factory. Bandar Maharani, here I come!!

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.. 

Second day without a collie. So far so good. Feels great to be in control of such a big workspace. I can divide it into quadrants to ease my work. The first quadrant is for the inverter, the second to put the instruction manual, the third to put another inverter and some empty space for the customer. The dispatch boy is absent so I get to use his desk too. 

Even with that kind of planning, the workstation was a mess! I often misplaced the screwdriver and took another one but it turns out that the screwdriver is just under the inverter cover beside me. That's how the mess escalates.

No fieldwork today. But Mr. James gave me a new brand of inverter to learn and test. This time its from Toshiba. Its a single phase, 200V, 2hp inverter. Much simpler than the Mitsubishi inverter. The Mitsubishi inverter has 800+ instructions or program codes while the Toshiba has less than 80 instructions so it's quite a straight-forward inverter. But there's a flaw. The control panel is in Japanese!!! (or is it Chinese?)

Fortunately the manual is in English. There's even a picture of the control panel that is in English. Phew~ At first it is very tedious to refer to that page each time I want to change the program codes. But once I get the hang of it, its very easy as if I was able to read Japanese! Spent the whole day working on this inverter to explore its functions.

After lunch Miss Goh asked me to tune a switching power supply unit (switching PSU) to output exactly 26.4V DC. The switching PSU normally outputs 24V DC but adjustable up to 27V. Took some patience to tune it with precision because there is a small delay before the value of the output stabilizes. After a few minutes I managed to tune it to exactly 26.4V as requested.

Around 10am a guy came in. He's an alumni from UPM. Now he's working in an electronics repairing company. We start to mingle and he told me that I should pursue my studies in PLC and automation engineering because the demand for such engineer is on the rise and selling these items can make a huge business. There are hundreds of factories in the vicinity of Shah Alam alone and they ALL need these automation machines to run. Now I'm seriously reconsidering what major I will take in my final year. Would it be Computer Engineering or Control and Automation Engineering?  

Shoot! I'm two days late! This post was supposed to be published two days ago! The reason is that I was involved with an activity in UNITEN yesterday. My beloved club, Persatuan Pembimbing Rakan Sebaya (PRSUNITEN) organized the Training of Trainers to prepare the committees for "Program Pintar". I was handling an activity similar to "explorace" together with the President and a few other committees. It was a great day!

I have successfully completed one-third of my internship! Status report: no broken equipment, full attendance, no "I can't take this anymore!!" attitude..yup, I'm still in good shape. Last Friday also happens to be my collie's last day in the office! I'll be all alone next week!

Summary of Friday's activity, I learned how to connect two power supplies in series to amplify its voltage and I learned about the Panasonic PLC and its programmer.

The power supply is actually an inverter. In converts a 240V AC to 48V DC but the output voltage can be adjusted up to 56V. The customer wants a 110V DC output so we connected two of them in series and adjusted the voltage. The setup is shown below:

Then I learned about the Panasonic PLC. The technique is pretty similar to a microcontroller. The PLC is connected to the PC with a serial cable, the program can then be uploaded and modified and downloaded back to the PLC. The only major difference is the programming language. The ladder diagram can be very difficult for beginners like me. 

Now that my collie has left the company, I'll be all alone for a while. Mr. James is still looking for interns to replace him. I am not very confident but hopefully everything that I learned from my collie is enough for the days ahead. Whatever that doesn't kill you, makes you stronger.