What is Interlocking in Railways? | Bandel Station largest Railways interlocking system in the world.

What is Interlocking in Railways? | Bandel Station largest Railways interlocking system in the world.1002 new routes are being added to Bandel railway station. According to railway sources, the new electronic interlocking system will be launched on May 30.

What is Interlocking in Railways?

You must have seen all kinds of railway yards, big or small while traveling by train. There are many lines in these yards. There are ‘points’ (POINTS) to connect them together. A motor is installed at each point to move the points. Then come the signals. You must have read one of my answers about signals. The signal allows the loco pilot to enter the railway station yard with his train.

What is Interlocking in Railways?
What is Interlocking in Railways?

A brief discussion of Interlocking in Railways

Locking is done between points and signals in such a way that after the points are set, the signal of the line whose route has been set comes. This locking is called signal interlocking. To explain this thing better, I am giving a picture of a four-line railway station below.

Look at the signal number S11 on the right-hand side in the above picture, there will be two yellow-colored V arms above the main signal unit. These are called junction-type route indicators. This route indicator tells the loco pilot on which line his train is being taken. This whole signal is called a home signal.

Read More: Bandel Junction New Technology 2022 | Electronic interlocking system

Now suppose the train is to be taken on the left side loop line then there are two points falling till home signal and next stop signal S13, first facing points have to be kept in normal position and second in reverse position, thus loop line set Will to happen.

Now when the signal of the loop line is given, big yellow light and five lunar white bulbs will light up in the left arm. This position will signal to the Loco Pilot to proceed that he has to go to the loop line. He will reduce his speed and enter the loop line at a speed of 30 kmph and stand on the platform before the next signal S13.

Read More : ব্যান্ডেল স্পেশাল ট্রেনের তালিকা 2022 (পিডিএফ ডাউনলোড করুন) | সময় (27 থেকে 30 মে)

Here the interlocking is that if the loop line is set then the mainline signal will not come and if the mainline is set then the loop line signal will not come. Another interlocking is that no other train should stand on the line on which the train is to be taken. This is achieved through track circuiting. A track circuit is made on each line.

If the train is standing on that line, then the relay of that track circuit will be down and it will not allow the signal of that line. Each such point has two relays, one for the normal setting and the other for the reverse setting. Electrical interlocking is done by these relays. The interlocking done by the relay is called relay interlocking.


In the picture, you can see that each of the points, track circuit, and the signal is connected by a cable to the relay room. They have relays in the relay room. An electrical circuit is made to clear the signal from the pickup and drop contacts of the relay. When the circuit is complete, the signal whose relay is pickup becomes clear.

This is just interlocking. There is a panel with the station master to operate all these. This panel is connected to the relay room. There are push buttons on this panel from which the station master can operate the points and signals in the desired position.

Interlocking Meaning In Bengali

পরস্পর আলিঙ্গনাবদ্ধ করা, একত্র সম্বদ্ধ করা, একত্র সম্বদ্ধ হত্তয়া, পরস্পর আলিঙ্গনাবদ্ধ হত্তয়া,

Syed Mosharaf Hossain
Syed Mosharaf Hossain
Hi, I am Syed Mosharaf Hossain, popularly known as Deep in my friends’ circle. I am a writer, author ,educationist and an researcher . I enjoy writing things that are on popular science, applied mathematics, environment, history, invention news , modern technology culture and society in Bengali in order to popularize science among readers in the regional language. Gold medalist, at Govt. of West Bengal district and state level Student-Youth science research competition 2015 & Inventor of women safety Shoe, Study- Engineering student

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