By the start of the 1980s Victorian Railways passenger numbers had fallen to around 3 million per year, due to ageing rolling stock, stagnant timetables and competition from other forms of transport. The Lonie Report of 1980 recommended cuts to the network, with the general public responding by calling for the State Government to maintain a viable rail network. The government response in February 1981 was the New Deal for Country Passengers, a $115 million commitment to recast country rail passenger services in Victoria.
As part of the New Deal all B class locomotives were to be re-built as the A class for use on passenger services and ten new locomotives ordered. Tenders closed in 1983 for the first 10 units, with Clyde Engineering being awarded the contract. By mid-1985 the rising cost of the A class conversions saw the project abandoned after 11 locomotives were completed, and the N class order increased to 25 using the parts intended for the A class conversions.
As part of the New Deal all B class locomotives were to be re-built as the A class for use on passenger services and ten new locomotives ordered. Tenders closed in 1983 for the first 10 units, with Clyde Engineering being awarded the contract. By mid-1985 the rising cost of the A class conversions saw the project abandoned after 11 locomotives were completed, and the N class order increased to 25 using the parts intended for the A class conversions.
The class entered service on the 1,600 mm (5 ft 3 in) and operated on main lines all over the state, with the exception of the Gippsland line beyond Traralgon, a restriction that was later lifted. The class also saw regular use on The Overland Melbourne to Adelaideovernight service until it was withdrawn for conversion to 1,435 mm (4 ft 8 in 1⁄2) standard gauge in March 1995. As well as being operated by V/Line, class members were hired to the Warrnambool line operator West Coast Railway from 1993 until its own locomotives became available in 1995, and to Shepparton line operator Hoys Roadlines between 1993 and 2004.
In preparation for privatisation the operations of V/Line Freight and V/Line Passenger were split in 1995, with the N class allocated to the passenger operator and included in the sale to National Express in 1999. Before this time the class had also been employed on freight services with a maximum speed of 90 km/h (56 mph).
During the Regional Fast Rail project, a number of shutdowns were carried out to normal passenger services, with the N class being used to haul ballast trains on the Geelong line in 2003/04, as well as being hired to Freight Australia in January 2004 to haul log and grain services. Since 2007 class members have also been hired to heritage operator Seymour Railway Heritage Centre for use on its trains, as the provision of TPWSequipment permits running at full line speed over the Regional Fast Rail network.
Today with the VLocity diesel multiple units having entered service, the N class play a lesser role, their main use being peak hour commuter services and InterCity services beyond the Regional Fast Rail network to Bairnsdale, Swan Hill and Warrnambool on the broad gauge and Albury on the standard gauge. The class are authorised to operate at 115 km/h (71 mph), but some units have been upgraded with D77/78 traction motors and have a maximum speed of 130 km/h (81 mph). As of 5th September 2017, all engines bar 452, 456, 461, 462 and 466 had been fitted with the upgraded traction motors.
In preparation for privatisation the operations of V/Line Freight and V/Line Passenger were split in 1995, with the N class allocated to the passenger operator and included in the sale to National Express in 1999. Before this time the class had also been employed on freight services with a maximum speed of 90 km/h (56 mph).
During the Regional Fast Rail project, a number of shutdowns were carried out to normal passenger services, with the N class being used to haul ballast trains on the Geelong line in 2003/04, as well as being hired to Freight Australia in January 2004 to haul log and grain services. Since 2007 class members have also been hired to heritage operator Seymour Railway Heritage Centre for use on its trains, as the provision of TPWSequipment permits running at full line speed over the Regional Fast Rail network.
Today with the VLocity diesel multiple units having entered service, the N class play a lesser role, their main use being peak hour commuter services and InterCity services beyond the Regional Fast Rail network to Bairnsdale, Swan Hill and Warrnambool on the broad gauge and Albury on the standard gauge. The class are authorised to operate at 115 km/h (71 mph), but some units have been upgraded with D77/78 traction motors and have a maximum speed of 130 km/h (81 mph). As of 5th September 2017, all engines bar 452, 456, 461, 462 and 466 had been fitted with the upgraded traction motors.
The N class feature a frame and body locally designed, but with imported Electro-Motive Division technology in the prime mover, generator and control unit, along with locally produced components such as the bogie frames by Bradford Kendall. The class was the first in the world to use the EMD D43 traction motor, similar to but smaller than that used in the C and G classes. Head end power is provided by a separate engine unit in a special compartment located at the number 1 end of the locomotive behind the electrical cabinet. The 240 kW generator provides 415V 3-phase AC power for train lighting, air conditioning and other carriage requirements.
Fitted with 6,800 litre fuel tanks the class were capable of running from Melbourne to Adelaide without refuelling. Electrical and electronic components are modular to minimise delays after failures, and a reactive muffler system reduces the exhaust noise level. While most of them have only been used on broad gauge, three of them have been converted to 1,435 mm (4 ft 8
Fitted with 6,800 litre fuel tanks the class were capable of running from Melbourne to Adelaide without refuelling. Electrical and electronic components are modular to minimise delays after failures, and a reactive muffler system reduces the exhaust noise level. While most of them have only been used on broad gauge, three of them have been converted to 1,435 mm (4 ft 8
- 1⁄2 in) standard gauge by exchanging the wheelsets and repositioning the braking equipment.