Protection Device

The prototype was designed as a tool for users to monitor the utilization of the current flow rate.

The advantages of this tool:

1. It can monitor the current consumption.
2. User can set the overload current depend on requirements.
3. This tool will trip when the current overflow and can saving electrical equipment users.
4. It can help users monitor the current flow in order to save electricity.

Open to companies willing to develop a tool. I can be contacted at the email address haszirul@yahoo.com.

Electronic Device

Subject : Electronic Device

Introduction :-
This course is introduced the students concept of semiconductors, diode, zener
diode, bipolar junction transistors, field effect transistors, power electronic
switching devices , opto-electronics devices and operational amplifiers


Outcome for this course :- 
1. Identify the symbol and structure of electronic devices. 
2. Explain the characteristics and functions of electronic devices.
3. Analyze the circuit of electronic devices by using appropriate techniques.
4. Conduct experiments as well as to interpret data through the practical.
5. Demonstrate competence in communication including writing, and
    speaking/presentation skills.

Introduction to Semiconductor

   Slide 1

Diode

Slide 2

Zener Diode

Slide 3

Bipolar Junction Transistor (BJT)

Slide 4

Field Effect Transistor (FET)

Slide 5

Introduction to Power Electronic Switching Devices

Slide 6

Introduction Opto-Electronic Devices

Slide 7

Operational Amplifiers 

Slide 8

Reference  : Thomas L. Floyd(2014). Electronic Devices Electron Flow Version (9 Edition)

Basic Wirelless Handphone Charging

Introduction

Currently, wireless power is very popular due to efficient energy transfer, short charging time and ease of use. But power shortages are common when transferring over longer distances. This is because they have limited distance between transmit and receive while charging process.

Basic  Theory
Faraday's law:

 Figure 1

From the figure 1 that shows EMF is proportional to the number of turns in the coil and multiplied by the rate of change of effective magnetic flux generated by the magnetic source. We will assume that the flux source will be the charging station. Mutual coupling is ignored and the charging station is assumed to be very close to the device, which means minimum flux leakage.

The Faraday's law is shown in figure 2. The EMF will be induced when they have movement from the magnet. The voltmeter is used to show the EMF was created. 

Figure 2

From the mechanism at figure 2 we can be used to charge a battery with a voltage rating lower than the EMF. Example, for a charger rating of 5 volts, 0.7 A charging a Li-ion battery of rating 3.7 volts 1650 mAh, i.e., the battery at a voltage of 3.7 volts can output 1.65 A for about an hour (or 6.11 Wh) it will take about 1 hour 45 mins to completely charge the battery from nil. Other factors like battery age and temperature also determines charging time.

Shows in figure 3, the EMF that induced at receiver is used to charge a battery, just like an AC adapter.

 

Figure 3

Figure 4 is shows the concept of charging station, Magnetic flux will be induced inside the coil. The principle of ampere circuit law [4] is used that can determine the magnetic field associated with a current. The EMF will control by number of turn coil and flux that induce.

Figure 4

How the wireless charging work for Smartphone.

Basically, wireless charging have 2 parts. It calls transmit and receive. They have no physical contact between this part. The electrical current is then used to charge or re-charge the battery at the smartphone.

Transmit (TX): The alternating current (AC) is sent to the transmitter coil from the transmitter circuit.  The AC then induces a time varying magnetic field in the transmitter coil.

AC will flowing within the transmitter coil and  magnetic field will induces which extends to the receiving coil (within a specified distance).

The magnetic field generates current within the receiver and transmit coil of the device.  The process also referred as magnetic or resonant coupling and is achieved by both coils resonating at the same frequency.

Receive (RX): Current will flowing within the receiver coil and converted into direct current (DC) by the receiver circuit, which will be used to charge the battery in smartphone

Source :

Referance :
1. http://powerbyproxi.com/wireless-charging/. 
2. https://www.quora.com/How-do-wireless-charging-pads-work.
3. http://www.qiwireless.com/wireless-charging-htc-one-m8/ (21 Dec 2015)
4. https://en.wikipedia.org/wiki/Amp%C3%A8re's_circuital_law

Memori di POLIMAS

Pada 3 Nov 2015 saya melakukan lawatan akademik ke jabatan mekanikal di Politeknik Sultan Abdul Halim Muadzam Shah (Polimas).Hati memang amat teruja kerana dapat kembali ke Polimas setelah hampir 20 tahun.Matlamat utama lawatan adalah bertujuan sebagai penanda aras dengan program Diploma Mekatronik (DEM) di Polimas.

Apabila sampai ke pintu masuk Polimas terasa seperti 23 tahun dahulu iaitu pada Jun 1993 dimana polimas menerima pelajar baru untuk kemasukan Jun 1995.Berbeza dengan 2015 banyak berlaku perubahan di dalam Polimas.Banyak pembangunan dilakukan di dalam kawasan Polimas selari dengan penambahan jumlah pelajar.Teringat pada zaman berlajar,berhujan dan berpanas untuk ke bilik kuliah dari asrama demi untuk menuntut ilmu.

Saya berdiri di hadapan pintu masuk ke lab utama jabatan elektrik.Satu ketika tempat ini digunakan oleh pelajar Sijil Kejuruteraan Elektronik Perhubungan (SEP).Bengkel yang biasa digunakan oleh kelas kami pada masa itu adalah lab basic elektrik,elektronik,instrumentasi dan lab telekomunikasi.

Satu ketika laluan ini digunakan untuk ke kelas Autocad.Dihadapan lab ini biasa diadakan perjumpaan kompeni C batalion 504 AW pada setiap hari jumaat.

 

Gambar di atas adalah laluan utama untuk ke asrama dari blok akademik. Kawasan lapang ini biasa digunakan oleh pasukan wataniah Polimas.

                                              Cousemate 23 tahun dahulu SEP4A

Satu ketika dahulu Polimas lah yang mengenalkan pendidikan teknikal sehingga berjaya sehingga sekarang.Bersama rakan-rakan mengharungi susah senang menyiapkan tugasan yang di beri oleh pensyarah.Sahabat saya sekelas telah berjaya dalam kerjaya masing-masing dan ada diantara mereka telah menyumbangkan bakti mengajar kembali di Polimas.