3 Phase Direct On Line Starter/ Explain with Circuit Diagram, DOL Direct online starter

Different starting methods are used to start 3 phase induction motor like star delta starter, autotransformer starter, variable frequency drive,soft starter,dol starter(direct online starter) because the Induction motor draws a large current at starting.

Direct On-Line is the simplest and cheapest method used for starting three-phase motor. Dol is used for up to 5 HP motor. dol starter is more popular due to the low price.

DOL starter connects the motor directly to supply without a reduction in supply voltage and applies full line voltage to 3 phase motor. this is the main disadvantage of dol starter.

A small HP motor can be started simply by plugging into the power supply. But large HP motor required a special unit called a motor starter.

Direct online starter for 3-phase induction motor contain parts like miniature circuit breaker (MCB) for motor protection purpose, overload relay, power contactor, fuse unit, start button, stop button.

Small size dol starter is operated manually but for larger HP motor, dol motor starter are operated using electromechanical contactor (relay) to switch motor ON and OFF.

DOL Motor Starter can be used, if a high starting current cannot cause an excessive voltage drop in the motor circuit.

The demerits of dol starter is that gives the highest possible current to motor. Which is 6 to 7 time of rated current of the motor.

Besides the DOL starter draws the starting current there also exists a current peak that can rise up to 14 times the rated current since the motor is not energized from the first moment when starting.

DOL starter control circuit diagram consist components like Main power contactor, start button, stop push button and overload relay is connected in series this circuit is called control circuit of dol motor starter. All controlling of starter are controlled by this circuit.

DOL starter power circuit diagram :
Direct Online starter power diagram has fuse unit, Main power contactor (K1), overload relay. Also, we can connect MCB for protection purpose in a direct On-Line motor starter.

[bradwendica]

When I was working before in the textile co. I was wondering how the motor can be controlled in more than three stations, I was a machine operator and know nothing about electricity but due to my interest, I leave the job, I apply for helper job and I was lucky to work in power plant and everything go in my desire and know the job and become an electrician, even motor rewinding.thanks for the video, a guide to someone who purshue an electrical job.

[eliaseve]

I love this, I did this last year had difficulty wiring in Lab. Am much better and would like to see more easy wiring. Definitely I will watch this video many times.

[danielteyehuago]

My biggest difficulty is understanding the circuit diagram, but you bringing it side by side with the wiring diagram makes sense to me.

[danielteyehuago]

Wow! This is video very informative and the best tutorial on the topic for me so far. I really appreciate it. Thanks for sharing it with us. Your ability to add the circuit diagram to your work makes you a top notch...

[andrewburn]

Best electrical channel Iv found in a very long time. 😊

[martinkoch]

You are making very useful vidoes, with nice explanations, thank you a lot!

[priyadharsanandharsanan]

Animation class wise very super and easily to

[stllim]

You provide a very good explanation.But a bit too fast.Please slow down the speed and movement of diagrams.Tq.

[siindian]

Sir, I have watched your videos is excellent and I want more Learn so please make a video for DG set deeply explain and open circuits fault also short circuits fault resolution single phase & three phase.👍

[essauchewe]

Thanks very much.Can you also do star delta control circuit

[muftahibrahimsahoub]

Thanks so much Eng.Gensis good information

[GodolfredoBellidoTurpo]

What program do you use to animate the circuit? Dear friend, thank you for the response.

[elohorolokpa]

I hope this can be used for heavy duty machines too.

[StreetArtistsOfTheWorld]

Make a video explaining the auxiliary contacts please, that is confusing to me and I still don't understant that concept well :(

[incredibleone]

plz make a vedio for control a three phase motor with forward and backward with dol method

[indu]

I want videos on ht induction motor along with panel
How circuit complete from transformer to panel to motor
How many components are there in between
What is working of each components.

[MushtaqAhmad-vwkc]

Sir very nice explanation..
Can you tell me which software you use here for circuit animations?

[SurajsinhKarande]

Please make video on digital Timer and connector wiring. Explain timer machanism as per connection

[documentales]

For what purpose is the auxiliary contact connected?

[lacoste]

Had to watch quite a few times where is the black neutral going ? I’m so confused