MI 79

MI 79 (Class Z 8100)
MI 79 train at Laplace station on the RER B line.
In service	1981–present
Manufacturer	Alsthom and Société Franco-Belge
Constructed	1980–1985
Entered service	1980
Refurbished	2010–2015
Number built	120 trainsets (480 cars)
Number in service	116 trainsets (464 cars)
Number scrapped	4 trainsets (16 cars)
Formation	4 cars per trainset
Fleet numbers	Z 8101–Z 8340
Operators	RATP
Depots	Massy Mitry-Mory
Lines served
Specifications
Car body construction	Aluminium
Train length	104.16 m (341 ft 9 in)
Car length	26 m (85 ft 4 in)
Width	2.8 m (9 ft 2 in)
Height	4.18 m (13 ft 9 in)
Doors	4 pairs per side, per car
Maximum speed	140 km/h (87 mph)
Weight	205,600 kg (453,300 lb)
Traction system	TCO[1] chopper/thyristor (analogic control)
Traction motors	8 x CEM/Oerlikon EHO 3262 A (750 V DC self ventilated)
Power output	2,824–2,480 kW (3,787–3,326 hp)
Transmission	Hollow shaft and cardan shaft ratio :4.047
Acceleration	1 m/s2 (3.3 ft/s2)
Deceleration	1.1 m/s2 (3.6 ft/s2) (emergency brake) 1.15 m/s2 (3.8 ft/s2)
Electric system(s)	Overhead line:     25 kV 50 Hz AC     1,500 V DC
Current collector(s)	Pantograph (type AM 62 BU)
Bogies	H-shape frame by ANF Industrie
Braking system(s)	Disc, regenerative, eddy current
Safety system(s)	EAS, KCVP, SACEM[2]
Coupling system	Scharfenberg
Multiple working	MI 79 or MI 84 maximum 3 trainsets
Track gauge	1,435 mm (4 ft 8+1⁄2 in) standard gauge

The MI 79 (French: Matériel d'Interconnexion de 1979, English: interconnection rolling stock of 1979), also known as the Class Z 8100 is a dual-voltage electric multiple unit trainset that is operated on line B of the Réseau Express Régional (RER), a hybrid suburban commuter and rapid transit system serving Paris and its suburbs. The MI 79, designed in the 1970s for the RER B which needed dual-voltage (interconnection) trainsets. They were followed by a derivative version, the MI 84, designed in the 1980s to meet the needs of the RER A line, before reassigned to the RER B in the 2010s.