18 Macam Hand Tools Yang Banyak Digunakan + Fungsinya

Bicara soal perkakas, ternyata banyak jenisnya. Ada hand tools, ada power tools dan ada SST (special service tools).

Apa itu hand tools ?

Sesuai namanya, hand (tangan) tools (perkakas) adalah alat atau perkakas yang penggunaannya mengandalkan tenaga tangan manusia.

Jadi bisa dikatakan, hand tools itu sebuah alat bantu dalam melakukan service, pembongkaran, atau pemasangan sebuah engine atau mekanisme lainnya.

Ada banyak perkakas yang masuk dalam kategori hand tools, beberapa contoh hand tools yang paling umum dan banyak digunakan pada ranah otomotif akan kita bahas dibawah.

Macam Macam Hand Tools Beserta Fungsinya

Macam macam perkakas tangan dibawah kami kelompokan berdasarkan jenis alatnya, ada 5 kategori pada hand tools yakni ;

A. Kunci/Wrench

Apabila anda akan mengganti oli sepeda motor, satu alat yang dibutuhkan adalah kunci untuk melepas baut olinya. Kunci atau dalam bahasa Inggris disebut wrench berfungsi sebagai alat bantu untuk memudahkan kita dalam melepas baut atau mur.

Kunci ini memiliki banyak jenis antara lain ;

1. Kunci pas


Kunci pas adalah sebuah kunci dengan bentuk segienam (tidak penuh) yang pas atau sesuai dengan ukuran kepala baut. Kunci ini banyak digunakan untuk melepas baut atau mur yang memiliki sela yang cukup sempit.

Namun karena bentuknya tidak melingkari baut secara keseluruhan, kunci ini kurang cocok saat dipakai untuk melepas baut yang sangat keras.

2. Kunci ring


Kunci ring adalah sebuah kunci yang memiliki bentuk segi 12 yang melingkari kepala baut. Kunci ini memiliki bentuk segi yang lebih banyak sehingga bisa digunakan pada sudut yang lebih leluasa.

Berbeda dengan kunci pas, kunci ring sangat baik saat digunakan untuk melepas baut yang keras karena bentuknya yang melingkari baut tentu bisa lebih aman.

3. Kunci kombinasi (pas ring)


Merupakan kunci yang memiliki dua bentuk yang berbeda pada kedua ujungnya, yakni ujung kunci pas dan kunci ring. Kunci ini dibuat untuk memudahkan mekanik dalam melepas/memasang baut yang kadang selanya menyulitkan.

4. Kunci T


Kunci T adalah sebuah kunci berbentuk T dengan ujung bawah berupa shock atau tabung yang masuk kedalam kepala baut.

Kunci ini biasa digunakan untuk melepas baut yang posisinya didalam lubang, dimana tidak memungkinkan kita melepasnya menggunakan kunci ring atau pas.

5. Kunci shock


Kunci shock adalah kunci berbentuk tabung yang masuk kedalam kepala baut seperti kunci T pada umumnya, namun kunci shcok ini bisa dilepas antara shocknya dengan handlenya jadi kita bisa menukan shock dengan ukuran sesuai ukuran baut.

6. Hexagonal L key


Hex key adalah kunci yang berbentuk segi enam kebalikan dari baut biasa, jadi kalau baut biasa itu berbentuk segi enam yang menonjol sementara baut ini memiliki bentuk cekungan segi enam sehingga butuh kunci segi enam yang bisa masuk kedalam cekungan tersebut.

Kunci ini biasanya dibuat dengan bentuk L sehingga sering disebut juga kunci L, tapi selain berbentuk L kunci hexagonal ini juga dibuat dalam bentuk shock yang dapat dipasang pada gagang shock biasa.

7. Torx L key


Kunci ini mirip dengan kunci Hexagonal, tapi bentuknya bukan segi enam melainkan bintang. Mobil-mobil Eropa dan Amerika banyak menggunakan baut bintang sehingga kunci ini juga sering digunakan untuk menservice mobil-mobil tersebut.

Sama seperti hexagonal key, kunci torx ini juga biasa dibuat dalam bentuk L dan ada pula yang dibuat dalam bentuk shock.

8. Adjustable wrench (kunci inggris)


Mungkin tidak perlu dijelaskan lagi, kunci ini bisa digunakan pada hampir semua jenis baut/mur segi enam karena memang kunci ini bisa diset sesuai ukuran baut/mur.

B. Tang

Kategori kedua adalah tang, tang merupakan alat khusus yang memiliki banyak sekali kegunaan. Bisa untuk menjepit, memotong, ataupun mencengkram.

Beberapa jenis tang yang banyak digunakan antara lain ;

1. Tang potong

Merupakan tang untuk memotong kabel, kawat atau logam tipis. Bentuk tang ini mirip seperti gunting dengan ujung pendek namun lebih kokoh.

2. Tang lancip


Tang ini memiliki ujung lancip seperti gunting, fungsi utamanya adalah sebagai penjepit terutama untuk komponen yang memiliki pegangan kecil. Dengan ujung lancip, tang ini mampu masuk ke sela sempit.

3. Tang kombinasi


Merupakan tang multifungsi yang bisa digunakan untuk memotong, ataupun menjepit. Jenis tang ini banyak sekali anda temukan karena yang paling umum digunakan pada perkakas rumah atau bengkel.

C. Obeng


Obeng adalah hand tools yang digunakan untuk melepas atau memasang sekrup. Meski demikian, bentuk obeng yang seperti tuas juga dimanfaatkan untuk hal lainnya seperti untuk mencongkel contohnya saat menyetel rem tromol.

Obeng secara umum hanya ada dua jenis yakni obeng + dan obeng -, keduanya dibedakan dari ujung obengnya.

Selain berbentuk + dan -, obeng sekarang juga bisa kita temukan dalam bentuk Torx (kunci bintang) dan hexagonal.

D. Handle shock

Merupakan alat bantu untuk mengaplikasikan kunci shock, alasan kita memisahkan ini dari kategori lain itu karena handle shock ini juga punya banyak jenis. Dan ini bersifat bongkar pasang, jadi bisa dirangkai dengan kunci shock apapun.

1. Ratchet handle


Merupakan handle shock yang dapat mengencangkan atau mengendorkan baut dengan mudah. Dengan ratchet ini, kita tidak perlu melepas kunci shock dari baut saat sedang mengendorkan/mengencangkan cukup bolak balikan handlenya.

2. T handle


Bentuknya seperti T yang dapat digeser, sehingga selain berfungsi sebagai T handle juga bisa difungsikan sebagai gagang shock yang lebih panjang.

3. Offset handle


Ini adalah handle shock yang panjang, biasanya digunakan untuk melepas baut besar dengan momen baut yang besar pula seperti mur roda dan baut-baut blok mesin.

4. Extension

Extension atau pemanjang adalah gagang shock yang berfungsi sebagai pemanjang sehingga kita bisa melepas baut/mur yang posisinya ada didalam dengan gagang shock masih diluar.

5. Adaptor


Merupakan sambungan khusus untuk menyambungkan kunci shock kecil dengan handle yanh lebih besar ataupun sebaliknya.

E. Palu

Palu atau hammer mungkin tidak perlu dijelaskan lagi anda pasti sudah tahu, standar pada bengkel biasanya memiliki dua jenis palu yakni palu besi (ball peen hammer) dan palu karet. Khusus Palu karet biasanya digunakan untuk melepas komponen yang mudah retak atau penyok.

Transistorized Ignition System Working and Diagram

Transistorized ignition system is an ignition scheme that reduces the use of mechanical devices, the purpose of transistorized ignition system is to improve the efficiency of the ignition system performance by replacing moving parts such as breaker points.

The main principle of transistorized ignition systems is to use transistors as electronic switches instead of breaker points.

For those of you who already know about vehicle ignition systems, you should know the breaker point or platinum.

Breaker point is a device used to break the primary coil current in the ignition coil so that electromagnetic induction can occur. This breaker point works mechanically by utilizing a cam that can stretch the breaker point gap.

However, the use of breaker points is considered to be less effective, it is because the rubbing components will erode so that it can affect the overall ignition system performance. In addition, when the breaker point is stretched, frequent sparking occurs at the breaker point so that the induction power of the ignition coil is reduced.

That's why there is breaker point gap adjustment.

By utilizing transistors the two things above can be overcome. So we don't need to set the gap.

Why are transistors used instead of breaker points?

As we said at the beginning, the transistor has a function as an electronic switch. There are three legs on the transistor namely base, collector, and emitter.

Collector is input, while emitter is output. The base as a controller, if there is an electric current (low voltage) flows at the base then the current at the input (collector) will flow to the output (emitter).

However, when the electric current at the base stops, the collector is cut off again with an emitter.

So in conclusion, the transistor can be used in the ignition system because of its characteristics that can disconnect and connect lines quickly.

To control the performance of the transistor, we need one additional sensor, the pick up coil. This sensor will send a low-voltage current with pauses according to the ignition timming at the base foot. So that the transistor performance will be matched with the engine RPM.

How does the coil pick up work?

Pick up coil consists of three parts, namely rotor with cam, permanent magnet and coil.


The three components are placed as shown, it is confirmed that the permanent magnet emits a magnetic field that hits the rotor. While the rotor is made of metal which is able to be attracted by magnets.

Cam on the rotor serves to shorten the gap between the rotor with a permanent magnet.

This changing gap causes the current in the pickup coil to be zig-zag. When the cam is parallel to the permanent magnet there is an electric current, but when the cam shifts the current disappears. This drop voltage is used as timming to break the primary current in the ignition coil.

Transistorized Ignition System diagram



  • Battery
  • Ignition switch
  • Ignition coil input
  • Primary coil output
  • Secondary coil output
  • Transistor
  • Pick up coil
  • distributor
  • Spark plug


Transisorized ignition system working procedure

When the engine is started, the crankshaft will rotate the pick up coil so that the pick up coil generates a low voltage current. This will cause the transistor base to be active so that the collector is connected to the emitter.

In the ignition coil, the current from the battery will flow in both coil in the ignition coil.

As explained above, the pickup coil will generate zig-zag electric current. Current from the pick up coil is then transmitted to the base leg of the transistor.

Induction in the ignition coil occurs when the base foot does not get an electric current, but it lasts for an instant, therefore in one cycle of the 4 cylinder engine can occur four times the induction process.

The induction produces high voltage which is distributed to the distributor to be distributed to each spark plug according to the firing order.

16 Special Service Tools (SST) Yang Banyak Digunakan Di Bengkel

Sesuai namanya, special service tools adalah perkakas yang dibuat special untuk men-service satu komponen tertentu.

Bahkan kadang, SST juga dibuat secara spesifik oleh pabrikan mobil untuk melepas atau memasang komponen pada mobil mereka. Hal ini dikarenakan ada beberapa komponen pada kendaraan yang memang tidak bisa dilepas apabila tidak menggunakan alat khusus.

Contoh yang paling mudah adalah alat untuk melepas ban dari velg, kalau anda pernah ke tukang tambal ban bagaimana mereka melepas ban motor anda ? pasti menggunakan alat seperti tuas.

Itu adalah contoh SST karena dibuat khusus untuk melepas dan memasang ban pada velg.

Selain itu ada banyak sekali, bahkan kalau dihitung bisa sampai ribuan karena seperti yang saya katakan diawal kadang tiap pabrikan mobil memiliki SST mereka sendiri jadi komponen yang harusnya bisa dilepas dengan kunci biasa pada mobil tertentu harus menggunakan SST.

Tapi yang akan kita bahas adalah SST universal atau SST yang memang digunakan untuk melepas komponen tertentu pada tiap kendaraan dan ini juga yang paling sering digunakan pada bengkel.

1. Piston ring compressor


Fungsi : untuk memasang piston (yang sudah dipasangi ring piston) kedalam silinder mesin.

Cara kerja SST ini adalah dengan mengincupkan ring piston sesuai diameter piston. Jadi saat piston dimasukan ke silinder, ring piston tidak mengganjal karena ring piston memiliki diameter lebih besar daripada silinder sehingga pasti mengganjal tanpa SST ini.

2. Piston ring expander


Fungsi : untuk melepas dan memasang ring piston pada piston.

Cara kerja SST ini seperti tang yang dapat merenggangkan ring piston sehingga ring piston bisa keluar dari alur ring piston pada piston dan bisa lepas dengan mudah.

3. Valve spring compressor


Fungsi : untuk melepas dan memasang katup mesin.

Cara kerja SST ini adalah dengan menekan pegas katup sehingga kita bisa melepas lock nut katup. Saat lock nut ini sudah terlepas maka katup dan pegas katup akan terlepas.

4. Oil filter remover


Fungsi : untuk melepas filter oli berjenis external oil filter.

Pada dasarnya, ada dua jenis filter oli. Ada filter oli dengan tabung didalam (tertanam pada blok silinder) dan kita hanya mengganti elemen filternya saja, ini biasa kita sebut internal oil filter.

Ada juga filter oli yang tabung beserta elemen filternya ada diluar, sehingga kalau ganti harus satu set dengan tabungnya. Filter jenis inilah yang memerlukan SST oil filter remover.

Pada dasarnya, SST ini digunakan untuk mencengkram tabung filter sehingga bisa diputar dengan lebih mudah.

5. Oil seal puller

Fungsi : untuk melepas seal oli pada beberapa komponen

Oil seal puller bekerja dengan mencongkel oil seal dari dudukannya, meski demikian bentuk SST ini disesuaikan agar saat mencongkel seal tidak berdampak pada kerusakan komponen lainnya.

6. Bearing cup puller

Fungsi : untuk menarik bantalan yang terpasang pada sebuah lubang.

SST ini bekerja dengan metode press yang dikendalikan dari putaran ulir, jadi untuk melepas bearing kita tinggal memutar tuas bagian atas.

7. Universal puller

Fungsi : untuk melepas atau memasang bantalan/bearing secara universal.

Pada dasarnya alat ini sama seperti yang diatas tapi sifatnya lebih universal atau bisa dipakai pada segala jenis bantalan.

8. Clutch central aligning tool

Fungsi : untuk membantu memasang disc brake/plat kopling supaya posisi lubang berada pada central.

Hal ini dikarenakan saat memasang plat kopling, plat kopling tidak memiliki acuan sehingga lubang porosnya harus benar-benar dipaskan supaya sentral. Apabila melese sedikit saja, poros transmisi akan sulit saat akan dipasang.

9. Bearing puller atachment

Fungsi : untuk melepaskan bearing yang yang posisinya berada didalam poros (bukan didalam lubang)

Cara kerja alat ini adalah dengan mencongkel bagian pangkal bearing, sehingga apabila bearing sedikit bergerak maka bearing bisa lebih mudah dilepas. alat ini biasa digunakan untuk melepas bearing pada poros transmisi yang memang keras untuk dilepas.

10. Sliding hammer

Fungsi : untuk menarik komponen dengan beban yang besar

Umumnya, sliding hammer digunakan untuk melepas komponen kaki-kaki yang sudah gancet atau melekat cukup lengket meski semua baut.mur sudah dilepas.

Cara kerjanya, dengan memberikan barbel pada sebuah poros dimana poros ini dihubungkan pada komponen yang akan dilepas. beban pada barbel memiliki gaya yang besar untuk menarik komponen.

11. Disc brake piston tool

Fungsi : untuk menekan piston pada caliper rem cakram supaya kembali merenggang.

Saat kita akan mengganti kampas rem, biasanya posisi piston pada kaliper rem lebih keluar. Kalaupun langsung dipasang dengan kampas rem baru, sudah pasti tidak akan masuk karena celahnya sangat sempit sehingga piston perlu dimasukan kembali.

SST ini dipakai untuk mengepress piston agar kembali rata dengan kaliper rem sehingga kaliper rem bisa dipasang dengan mudah.

12. Coil spring compressor

Fungsi : untuk menekan coil spring agar kita bisa dengan mudah melepas upper holder shockbreaker

Tanpa SST ini, kita akan kesulitan saat melepas upper holder shockbreaker karena ada tekanan dari coil spring.

Dengan SST ini, kita bisa meniadakan tekanan dari spring sehingga bisa dengan mudah melepas upper holder shockbreaker.

13. Ball joint separator


Fungsi : untuk melepas ball joint dari steering knuckle

SST ini mirip penjepit jemuran, cara kerjanya dengan menekan baut ball joint dengan bantalannya adalah knuckle. Cara ini lebih aman daripada cara konvensional dengan memukul bagian steering knucklenya.

14. Tie rod remover


Fungsi : untuk melepas tie rod end

Alat ini cara kerjanya hampir sama dengan ball joint separator tapi dengan jangkauan lebih besar. Hal ini dikarenakan panjang ball joint pada tie rod end juga kadang lebih panjang.

15. Differential flange holder


Fungsi : menahan flange pinion agar tidak diputar saat dilepas

Flange pinion yang ada pada input differential ini harus ditahan saat akan dilepas, untuk menahannya kita menggunakan flange holder yaitu berupa tuas dengan ujung dibaut ke flange sehingga kita bisa menahan flange pinion dengan SST tersebut.

16. Obeng ketok

Fungsi : untuk melepas sekrup yang susah dilepas menggunakan obeng biasa

Obeng ketok sering sering sekali digunakan, SST ini pada dasarnya sama seperti obeng dengan mata + dan -. Namun ada mekanisme dimana saat kita ketok handlenya, maka ujung obeng akan berputar. Oleh sebab itu obeng ini diberi nama obeng ketok.

Selain 16 SST diatas tentu masih ada banyak SST yang belum dibahas, tapi kira kira yang paling banyak digunakan itu ada diatas.

Motorcycle CDI Ignition System Parts and Functions

CDI system is one type of ignition system that is widely applied to motorcycles. The CDI system uses the discharged voltage from the capacitor to induce an ignition coil.

As discussed before (CDI system working principle), the CDI system is very different from conventional ignition systems such as battery ignition or magneto ignition.

Then what are the components of the CDI system? let's discuss.

6 Parts of CDI Ignition system and function


Why only 6? that's because the design of the CDI system is simpler so it doesn't need a lot of parts.

1. Source of energy (altenator or battery)

The first component is the energy provider, there are two types of components that can be used as energy providers in the CDI system, alternator and battery.

The alternator can generate electrical energy when the engine crankshaft rotates, the electric current generated is AC. While the battery, is a component of storing electrical energy. The battery can deliver electrical energy directly without turn the engine crankshaft. The electric current generated is DC.

From the explanation above we can see that there is a striking difference between the alternator and battery, the alternator produces AC current while the battery produces DC current. That is why there are two types of schemes in the CDI system, namely the AC CDI system (using an alternator) and the DC CDI system (using batteries).

Although the types of currents are different, both types have the same process. In an AC CDI system, the AC current will be converted into DC by a diode in the CDI unit.

2. CDI unit

CDI unit is a unit that contains several electronic components to trigger the induction of the ignition coil.

So, in this system CDI unit has the same function as breaker point on conventional ignition system.

What are the components in a CDI unit?

  • Diode (AC CDI system)
  • Voltage amplifier (DC CDI system)
  • Capacitor
  • SCR


Diodes are electronic components that have function to convert AC current into DC. As explain in the first point, in the AC CDI system the source of electricity is obtained from the alternator. But the alternator produces AC current.

Therefore, the diode acts as a hardware to convert AC current into DC.

While the voltage amplifier is a special component in the DC CDI system which has function to increase the battery voltage from 12 V to 200 V. This is because the capacitor requires around 200 V voltage for charging while the battery voltage is only 12 V.

But why does the AC CDI system not have a voltage amplifier?

The answer, because the voltage generated by the alternator has reached 200 V so it does not require a voltage amplifier.

Capacitor is an electronic component that can store a voltage at a certain capacity and can release the stored voltage simultaneously. In CDI systems, the discharged voltage of the capacitor is used to induce an ignition coil.

We know before that the capacitor has been charged by the electricity provider (alternator / battery) with a voltage of around 200 V. The voltage will be released simultaneously to cause a very large induction.

While the SCR (silicon controlled rectifier) ​​is a component to determine when the capacitor charged and when the capacitor discharged.

The works of SCR is by open the gate from the power source channel directly to the ground. That will make the current from the power source flow directly to ground so that the capacitor can release voltage.

3. Pick up the coil

The pickup coil is a detector to detect ignition timming. The pickup coil consists of a coil placed near the crankshaft. On the crankshaft there is a protrusion that will hit the pickup coil, this protrusion indicates ignition timing.

When the pickup coil hits the cam, the pickup coil will send pulses or electric waves.

The pulse is sent to the SCR to determine the capacitor. So the pulse from the pick up coil becomes the guidance of the SCR to be active.

4. Ignition coil

The ignition coil on the CDI system works when there is a voltage being applied, this is different from a conventional ignition system that utilizes a drop voltage to induce an ignition coil.

So the ignition coil design is slightly different.

In general the ignition coil on the CDI system is the same as the step up transformer, where the secondary primary has a coil of 100 times more than the primary coil. This causes the secondary voltage to be 100 times greater than the primary voltage, so that when the discharged voltage from capacitor is aplied, then the voltage produced by the ignition coil reaches 20,000 V.

5. Ignition switch

Ignition switch is a device to activate and deactivate the CDI system as a whole. Ignition switches are usually controlled by an ID key, each vehicle has a different key channel.

6. Spark plug

The function of the spark plug is to convert 20,000 V electrical energy into an electric spark. the way the spark plug works is actually quite simple, just by providing a gap between the electrode (+) and ground (-).

Automatically, an electric spark will be formed because the voltage of 20,000 V is very large and is able to jump electrons.

How CDI Ignition System Works On Motorcycle? Check This Out

In the previous article we have discussed the magneto ignition system, where this system is used on small gasoline engines such as on motorcycles.

In addition, there is an ignition system on the motorcycle that is more effective than magneto.

That is CDI (capacitor discharge ignition).

Then what is CDI? How does it work ? and what's the difference with the magneto ignition system? let's discuss together.

CDI Ignition System Definition


CDI consists of two main words, namely capacitor and discharge.

So, the CDI system can be interpreted as an ignition system that utilizes discharging current on the capacitor component.

What is capacitor?

Capacitor is an electronic component that can store electric current, and can release (discharge) the stored current spontaneously.

In conventional ignition systems such as magneto or battery ignition systems, the use of capacitors is only to prevent sparking at the breaker point. But on CDI systems, capacitors have a major role.

The release of current on the capacitor serves to induce the ignition coil.

This is the first difference between conventional ignition systems and CDI. In conventional ignition systems, induction of the coil occurs when the primary current is cut off. But on CDI, induction actually occurs by releasing more current to the primary coil coil.

Please note, the discharge current of this capacitor can reach 400 volts so that the output voltage can still be increased up to 20,000 V by an ordinary step up transformer induction.

For more details, see the diagram below


Components marked above
  • Alternator, as a source of electric current
  • Ignition switch
  • CDI Unit, in which there are several components such as capacitors, series of diodes, SCR (silicon controlled rectifier)
  • Pick up coil, to find out ignition timming
  • Step up / ignition coil transformer, used to increase the secondary voltage up to 20 KV.
  • Spark plug


The alternator used in the CDI ignition system can produce AC voltages between 100 - 400 V. This current is used as the basis for the induction process.

Then how is the process going?

1. Electricity generation on the alternator

Starting when the engine crankshaft is rotated, the energy to rotate the crankshaft get from mechanical energy (kick start) or electric (motor starter).

Previously, in the alternator there were two main components, namely the rotor magnet connected to the crankshaft and the stator coil located around the magnet.

Crankshaft rotation will rotate the rotor magnet on the alternator, the result is the stator coil produces AC voltage. The voltage produced by this alternator ranges from 100 V (low RPM) to 400 V (high RPM). This electricity is then used as an energy source for the ignition system.

2. The process of charging the capacitor

In this process, electric voltage from the alternator is flowed into the CDI unit, inside the CDI unit there are several parts such as;

  • Diode, serves to change the AC current into DC
  • Capacitor, as a storage and electric discharge
  • SCR


The voltage from the alternator will be directly sent to the capacitor, but because the current is still in the form of AC (alternate current), it needs to be changed to DC (direct current).

Therefore, before the current enters the capacitor, it will pass through the diode.

After passing the diode, the current is change from AC to DC and is directly used to charge the capacitor.

3. The discharging capacitor process

The capacitor can release a voltage that was previously stored, if there is no current source that hits it.

Therefore, to make the capacitor discharge its voltage, the primary voltage circuit of the capacitor must be disconnected or at least prevent the voltage from passing through the capacitor.

But how ?

For this matter, we are not talking about breaker points anymore, in the CDI system it is strongly influenced by two components namely the pick up coil and the SCR (silicon controlled rectifier).

Pick up coil is a coil that will conduct electric waves when there is a magnetic field passed it. That means, the pickup coil must be equipped with a magnet as a triger. The pickup coil is mounted near the rotor magnet, while a small magnet is connected to the crankshaft where the angle adjusted to the engine's timming.

When the crankshat rotates, this small magnet will rotate and each rotation this magnet will induce pick up coil oncel. When this process occurs, the pickup coil will generate electrical waves which are sent to input 2 on the CDI unit.

Then the electrical wave from the pickup coil is sent to the SCR. The function of the SCR is to activate the path from the alternator directly to ground.

For this SCR to work, a triger is needed. This triger is provided by the coil pick up. When an electric wave from the pickup coil enters the SCR, it will ignite the SCR to active.

As a result, the voltage from the alternator will directly flow to the ground because the nature of the electric current is always flowing to the ground with the smallest resistance.

When the voltage flows to ground, there is no more supply to fill the capactitor and this makes the capacitor also release its voltage.

4. Induction process on ignition coil

In the circuit above, it appears that the capacitor is connected to the primary coil. When the capacitor releases the voltage, there will be massive voltage flow to the primary coil suddenly, the voltage can reach 400 V.

Through induction on the ignition coil, a primary voltage of 400 V can change to 20 KV on the secondary coil. Then the voltage from the secondary coil is connected to the spark plug.

Induction on the ignition coil will occur for a moment because all voltage in the capacitor will be released at one time. That is why, spark on the spark plug is also only for a moment.

To do the induction in the next cycle, the capacitor need to charge back. It do by turned off the SCR so that the voltage from the alternator can flow back to the capacitor and chagrge it.

The SCR will be active and periodically inactive according to the triger of the pickup coil.

As explained above, the SCR will work when there is an electric wave coming from the pick-up coil while the pick-up coil will generate electric waves when a small magnet passes through the pick-up coil. When the magnet is pulled away it will automatically eliminate electric waves and the SCR is deactivated.

How Does Magneto Ignition System Works? Check Article Below

In the previous article, we discussed anything about the battery ignition system, but there is another ignition system that is almost similar. Magneto ignition system, then what is a magneto ignition system? How does it work ?

In general, the battery and magneto ignition systems are the same as conventional because they still use a mechanical breaker point to induce the coil.

But the difference is located in the source of energy.

We know that the battery ignition system has an energy source from the battery, but what about small engines that don't have batteries? Where does the energy source come from for the ignition system?
chain saw use a magneto system

Then the magneto ignition system is the solution, the magneto ignition system does not require an energy source such as a battery because the power source will be generated by the engine itself.

A mini generator is connected to the engine crankshaft, it will produce electricity when the crankshaft rotates.

The excess does not require a battery, so the engine design can be very light, but for performance it is clearly less than a battery ignition system that has a stable voltage.

Therefore, magneto is widely applied to small gas engines such as chain saws, tractors, air pumps, ATVs, speed boats, motor cylcle.

Then How Does the Magneto Ignition System Work?

As always, we first discuss the components.

  • Magneto unit
  • Ignition switch
  • Breaker point
  • Capacitors
  • Spark plug


The most influence part is the magneto unit, this component not only as a provider of electric current but also has functions as an ignition coil, so naturally in this system we do not see ignition coil components such as the battery ignition system.

Magneto is basically a mini generator, which is there is a permanent series of magnets connected to a crankshaft and two coils around the magnets.

How magneto works is also the same as generators in general, when the permanent magnet rotates there will be intersection of the magnetic force lines so as to produce an electric current in the coil around the magnet.

However, there are two coils inside the magneto, namely the primary coil and the secondary coil. The secondary coil has 20,000 turns and is connected to the spark plug while the primary coil has 200 turns and is connected to the breaker point circuit.

The operational order is the magneto ignition system

1. Start when the engine crankshaft is rotated

The energy to turn the crabkshaft is obtained from an external non-electric source such as a crankshaft rotator or on the motorcycle is a kick starter.

When the crankshaft rotates magneto will produce electricity in both coils with a relatively small voltage.

Meanwhile, the ignition system need extremely high voltage. Therefore, there must be an induction process to produce extremely high voltages.

2. Electromagnetic induction to increase the secondary coil voltage

To increase the voltage to 20,000 V, it is necessary to do an induction process between primary and secondary coil in magneto.

The induction process is also the same as a battery ignition coil where the induction will occur when the magnetic field collapsed from the primary coil into the secondary coil.

To make the magnetic field collapse, the current in the primary coil must be cut off suddenly. In charge of deciding the primary coil current is a series of breaker points.

This circuit consists of a breaker contact and a capacitor.

Breaker contact is a connector from the primary coil to the ground, but this contact can be disconnected by a cam that is also connected to the crankshaft. This means that on certain timings (combustion timming) the cam will hit the breaker point and break the primary coil current.

While the capacitor is in charge of absorbing current from the primary coil when the breaker contact is open.

Capacitor is an electronic component that can absorb the current about it, when the breaker contact is still closed, the current from the primary coil goes directly to the ground but when the breaker contact is open, this current will be absorbed into the capacitor.

The main purpose of the capacitor is actually to prevent the spark on the breaker contact, that is because the gap on the breaker contact is so small that the current from the primary coil is still possible to jump.

What are the advantages of the magneto ignition system?

  • Does not require a battery
  • Light-design
  • Components are simpler and fewer


What is the lack of a battery ignition system?

  • Sparks on small spark plugs when engine RPM is low
  • When the engine RPM is high, the spark on the spark plug is also quite large
  • Need more effort to start the engine

How Does Ignition Coil Works? Let's Discusse

Why does the ignition system have an ignition coil? what is its function and how does it work? We have written all the explanations below.

Ignition coil is one of the main components in the ignition system. The function of the coil is to change the battery voltage from 12 V to 25 KV.

Some people assume that ignition coil is only found in traditional ignition systems such as battery ignition systems or magneto ignition systems.

In fact, ignition coil can also be found on cars manufactured today. However, the igniton coil has changed a lot.

In the past, there was only one tubular coil that worked for all spark plugs. But now, there is a single coil or dual coil pack system where an engine does not only have one coil for all but one coil for each spark plugs.

What is the ignition coil function?

Its function is only to increase the ignition voltage.

Why does the ignition voltage have to be increased?

The reason is that in order to create a fire jump on the spark plug the battery voltage must be increased thousands of times. If the voltage is only 12 V then there will not be a stepping flame on the spark plug electrode, because to make electron jumps in an air gap, a large voltage is needed.

How does the ignition coil work?

To understand the working principle of an igniton coil, you need to study the igniton coil diagram below.


Main Ignition coil component

  • Primary winding
  • Secondary winding
  • Iron core


In general, ignition coil works the same as step up transformer. Step up transformer, using the electromagnetic induction method to increase the input voltage.

The way it works, there are two coils. Primary and secondary coils, primary coils are located inside while  the secondary coils located in outer side, so the magnetic field of the primary coils will hit the secondary coils.

If the number of turns of the secondary coil is less, the output voltage will decrease but if the number of turns of the secondary coil is higher then the output voltage will increase.

That is what happens during induction.

But on ignition coil, there is a little difference. In the ignition coil, the secondary coil is located inside the primary coil as illustrated above.

Then how does induction take place?

It turns out that the induction of the ignition coil does not occur when there is a current that passes through the igniton coil but it occur when the current in the ignition coil is cut off.

Primary coil will issue a magnetic field when electrified, this magnetic field will occur in the outer area due to the position of the primary coil in the outside area. When the electric current is cut off, the magnetic field that was previously formed will move very quickly towards the inside before finally disappearing.

The fast and simultaneous movement of the magnetic field will induce secondary coils with stronger results.

As a result, the secondary voltage has increased hundreds of times from 12 V to around 25 KV.

Then what is the function of the iron core in the ignition coil?

Its function is to pull the magnetic field from the primary coil, so that the movement of the magnetic field described above will be focused in very quickly.

The good conductor like iron, will be very effective to maximize the induction in the coil. Without this iron core, it is possible that the induction results could not reach 25 KV.