Indian Railway: Whenever you travel by Indian Railways, you must have noticed that P5 and P7 are written in big letters on some locomotives. But, do you know the meaning of these two words? Through this article, we will understand the meaning of both these words.
Indian Railway: Every day a large number of people travel on Indian Railways. Also, goods are transported in large quantities from one place to another by goods trains. Powerful engines of Indian Railways work to speed up these trains. Whenever you reach the railway station, you must have seen such engines in front of you, on which P5 and P7 are written. But, do you know why it is written on the railway engine and what it means? If not know, then you will get to know it through this article.
Indian Railways assigns a number code to identify the locomotives. By this, it is known which engine belongs to which category and how powerful it is in the end. The engine is employed according to its class.
The locomotives marked WAP-5 and WAP-7 are wide gauge high-speed electric locomotives used and operated by the Indian Railways. This is often a white-colored electric locomotive.
Now understand the meaning of these words
W in WAP stands for wide gauge. Wherein, A stands for Alternating Current or Electric and P stands for Passenger. Then the numbers at the end refer to the horsepower that the locomotive can generate. This means here 5 means 5000 horsepower and 7 means 7000 horsepower.
What are the features of WAP-5 and WAP-7?
The first WAP-5 locomotive engines were imported from ABB Switzerland in 1995 under a technology transfer pact. The most important feature of this engine is that it has a higher speed than any existing locomotive of Indian Railways. Let us tell you that the first 10 locomotives being imported had a speed limit of 150 km/h only. But, it was later made capable of an operational speed of 200 km/h and a maximum permissible speed of 225 km/h. In addition, the locomotive coupling system was also redesigned and an alternative drive gear assembly coupling system was added to these locomotives from Harth Coupling System for better compatibility with passenger trains of Indian Railways. In addition, these locomotives have provision for TAPS from the main loco transformer for hotel load. That is, it has the full capability to pull trains as a HOG locomotive. The WAP-5 locomotive can provide 5000 hp and 6000 hp at peak. Its main feature is regenerative braking. The braking system of this locomotive includes 160 kN (36,000 lbs) regenerative brakes, loco disc brakes, automatic train air brakes, and charged spring parking brakes.
Whereas, WAP-7 is one of the most successful locomotives of Indian Railways serving passenger trains for more than 23 years. It is a passenger version of the WAG-9 freight locomotive with modified gear ratios to haul lighter loads at higher speeds. With an output of 6,350 hp (4,740 kW), this WAP-7 engine is the most powerful passenger locomotive in the Indian Railways fleet, capable of hauling 24-coach trains at speeds of 110–140 km/h (68–87 mph). In 2019, a variant of the WAP-7, the WAP-7HS, was introduced for higher speeds. The WAP-7HS has a top speed of 180 km/h (110 mph). It is capable of pulling a 24-car train at 160 km/h (99 mph). Plans are also underway to use WAP-7HS for Shatabdi, Rajdhani, and Duronto Express trains.
