Multiple units of India#SSEMU

Most MUs are powered either by traction motors, receiving their power through a third rail or overhead wire (EMU), or by a diesel engine driving a generator producing electricity to drive traction motors (DMU).

A MU has the same power and traction components as a locomotive, but instead of the components being concentrated in one car, they are spread throughout the cars that make up the unit. In many cases, these cars can only propel themselves when they are part of the unit, so they are semi-permanently coupled. For example, in a DMU one car might carry the prime mover and traction motors, and another the engine for head-end power generation; an EMU might have one car carry the pantograph and transformer, and another car carry the traction motors. MU cars can be a motor or trailer car, it is not necessary for every one to be motorized.

=== Rapid transit ===

File:DelhiMetroBlueLineBombardier.jpg]]

There are currently 16 operational rapid transit (popularly known as 'metro') systems in fifteen cities across India. With Delhi Metro being the largest metro system which connects too few other nearby cities in the National Capital Region.{{cite web|url=https://www.livemint.com/Politics/ylEObaYWxcC7lGO2E2e4wJ/The-rise-of-metro-rail-network-in-India.html|title=How metro rail networks are spreading across India|first=Jyotika|last=Sood|date=26 July 2017|website=livemint.com}} As of October 2022, India has {{Cvt|810|km|4=0}} of operational metro lines and 631 15 systems.{{cite news|url=https://timesofindia.indiatimes.com/city/gurgaon/metro-lines-cover-only-3-of-gurugram/articleshow/70905439.cms|title=Metro lines cover only 3% of Gurugram | Gurgaon News - Times of India|website=The Times of India|date=30 August 2019 }} A further 568.15 km of lines is under construction.

Metro trains are all electric multiple units (EMUs). Different metro systems have different configuration of trains. Earlier metro lines tended to use the mainline {{Track gauge|indian|allk=on}} while most of the more recent systems instead opt for {{Track gauge|standard|allk=on}} for economies of scale with international systems. Power is varyingly supplied by either 750 V DC third rails as is typical on older metros in areas such as North America, Europe, the Middle East, Southeast Asia, and the former Soviet Union, or 25 kV AC 50 hz overhead catenary, which is very rare on metros outside of India. Delhi Metro uses Hyundai ROTEM EMUs and Bombardier MOVIA EMUs. Mumbai Metro uses CRRC, BEML EMUs.{{cite web | url=https://www.livemint.com/news/india/mumbai-gets-first-make-in-india-metro-coach-where-you-can-even-carry-bicycles-see-pictures-1568097462016.html | title=Mumbai gets first Make-in-India metro coach where you can even carry bicycles | date=10 September 2019 }}

=== Suburban ===

File:AC-EMU-Mumbai.jpg]]

Suburban rail is a rail service between a central business district and the suburbs, a conurbation or other locations that draw large numbers of people daily. The trains are called suburban trains. These trains are also referred to as "local trains" or "locals".

Suburban trains that handle commuter traffic are all electric multiple units (EMUs). They usually have nine or twelve coaches, sometimes even fifteen, to handle rush hour traffic. One unit of an EMU train consists of one power car and two general coaches. Thus, a nine coach EMU is made up of three units having one power car at each end and one at the middle. The rakes in the suburban rails run on 25 kV AC.{{cite web|url=http://www.irfca.org/faq/faq-elec.html#volt|title=[IRFCA] Indian Railways FAQ: Electric Traction — I|website=[IRFCA] The Indian Railways Fan Club|access-date=14 September 2017}} The suburban railways of Mumbai, Kolkata and Chennai occupy no more than 7.1% of the Indian Railways network, but account for 53.2% of all railway passengers.{{cite web|url=https://www.newslaundry.com/2015/09/07/why-indias-metro-and-suburban-railways-should-merge|title=Why India's Metro and suburban railways should merge|last=Chaturvedi|first=Sumit|date=7 September 2015|website=Newslaundry|access-date=14 September 2017}} In some cities of India, the opening of rapid transit systems has led to a decline in the use of the suburban rail system.{{cite news |last= Varma|first= Vishnu|date= 11 March 2016|title= Ring Railway left behind as Delhi swells beyond boundaries|url=https://indianexpress.com/article/cities/delhi/ring-railway-in-an-ever-expanding-delhi-a-ghost-railway-service-lingers/ |work= The Indian Express|location= New Delhi|access-date=4 December 2021}}

File:BEML SSEMU Photo 1.jpg]]

SSEMU is an acronym for Stainless steel EMU. Most modern SSEMUs are produced by BEML, it's manufacturing procedure and internals are different from MEMUs. It is specifically developed for coastal cities like Kolkata, Mumbai, Chennai etc. It is basically used of stainless steel for reducing corrosion and reducing the maintenance cost of MEMUs. Indian Railways has already deployed SSEMU in coastal regions of West Bengal and Tamil Nadu.{{cite web | url=https://www.slideshare.net/engineeringwatch/beml-limited-27234945 | title=Beml limited }}{{cite web | url=https://www.newindianexpress.com/cities/chennai/2019/may/30/southern-railways-gets-energy-efficient-emu-rakes-1983551.html | title=Southern Railways gets energy-efficient EMU rakes }}

File:DEMU_Local_at_Sitaphalmandi_railway_station.jpg

The DEMUs and MEMUs are diesel multiple units (DMUs) and electric multiple units (EMUs) that serve short and medium-distance routes in India, as compared to normal EMU trains that connect urban and suburban areas. The acronyms stand for "Diesel-Electric Multiple Unit" and "Mainline Electric Multiple Unit".{{Cite web|last=TTI|title=MEMU Trains in India|url=http://www.totaltraininfo.com/memu.php|access-date=8 February 2021|website=Total Train Info}}

These have two-sided cabs for changing and reversing the route, which is a bigger advantage over the attachment-detachment process of rakes and locomotives. Indian Railways (IR) is progressively replacing all locomotive-hauled slow and fast passenger and intercity trains with various EMUs. After replacing with EMUs, passenger trains would be re-branded as either MEMU or DEMU.

=== Vande Bharat Express ===

The Vande Bharat Express, previously known as Train 18,{{cite web|url=https://www.ndtv.com/india-news/train-18-indias-fastest-named-vande-bharat-express-piyush-goyal-1983965|title=India's fastest to be called Vande Bharat Express|work=Indian Express|access-date=28 January 2019}} is a semi-high-speed, electric multiple unit train,{{citation|title=Train 18, India's first engine-less train, set to hit tracks on October 29|date=24 October 2018|url=https://indianexpress.com/article/india/train-18-indias-first-engine-less-train-set-to-hit-tracks-on-october-29-5415892/|work=The Indian Express}} operated by the IR on few routes. It is a seater train which serves medium to long distance routes.

The Vande Bharat Express's exterior appearance consists of aerodynamic design, narrowing at each end of the train which is designed to combat air resistance.{{cite news|url=https://economictimes.indiatimes.com/industry/transportation/railways/train-18-countrys-first-engine-less-train-rolled-out-train-20-next/articleshow/66419774.cms|title=Train 18: Country's first engine-less train rolled out; Train 20 next|date=29 October 2018|work=The Economic Times|access-date=5 November 2018}} It has a driver cabin at each end, allowing for faster turnaround at terminating stations.{{cite news|url=http://www.uniindia.com/news/india/self-propelled-train-18-debuts-for-trial-run/1391824.html|title=Self-propelled Train 18 debuts for trial run|date=29 October 2018|work=United News of India|access-date=4 November 2018}} The train has 16 passenger cars, with a seating capacity of 1,128 passengers.{{cite news|url=https://www.business-standard.com/article/indian-railways/the-crown-jewel-of-indian-railways-is-a-billion-rupee-made-in-india-train-118102900370_1.html|title=Train 18, India's first engine-less train, is also the country's fastest|last1=Shine|first1=Jacob|date=29 October 2018|work=Business Standard|access-date=4 November 2018|location=New Delhi, India}} The chassis of a coach is 23 meters long, and the frame of the train is made entirely of stainless steel.{{Cite web |last=Gupta |first=Moushumi Das |date=23 October 2022 |title=Hi-tech machines, 9,000+ workforce — inside Integral Coach Factory making Vande Bharat trains |url=https://theprint.in/india/hi-tech-machines-9000-workforce-inside-integral-coach-factory-making-vande-bharat-trains/1175653/ |access-date=24 October 2022 |website=ThePrint |language=en-US}}

Alternate coaches are motorised to ensure even distribution of power and to help in quicker acceleration and deceleration. The gangways are interconnected and fully sealed to allow better mobility between coaches and to reduce noise respectively. The train features GPIS-based passenger information system, bio-vacuum toilets, and rotational seats which can be aligned in the direction of travel (only in executive class).{{cite web|url=https://www.thehindu.com/news/national/train-18-top-features-and-facilities-of-the-countrys-fastest-train/article25652410.ece|title=Train 18: Top features and facilities of the country's 'fastest train'|work=The Hindu|date=3 December 2018}}

=== Tram ===

File:Kolkata transport.jpg

The double-coach trams in Kolkata are also multiple-units. The pantograph which draws power is in one coach and another coach is a trailer coach. Cabs are there at both ends.

{{further|Multiple unit#Comparison to locomotive-hauled trains}}

• Locomotives of India
• Rail transport in India
• Indian Railways

{{reflist}}

{{commons category|Multiple units, motor coaches and railcars of India}}

{{Indian Railways}}