E993 series

The E993 series, branded the AC Train, was a Japanese experimental articulated electric multiple unit operated by the East Japan Railway Company from February 2002 to July 2006.
==History==
This five-car articulated set was introduced in 2002 to test and evaluate technologies and features to be used in future train designs, such as externally-mounted sliding doors and double-skin body construction. It was branded the AC Train (stylized ac@train), which stood for "Advanced Commuter Train."
The set was tested on the Kawagoe Line from 2002 to 2006 and it even carried commuters during its test run. The set was withdrawn on 14 July 2006 and was hauled to Kōriyama Works for scrapping; no cars from the set have been preserved.
The E993 series' legacy lived on in the also-experimental E331 series set introduced on the Keiyō line in March 2007.
==Design==
This five-car set consisted of five cars mounted on shared bogies between the diaphragms, for a total of six bogies.
==Specifications==
Cars 1 and 2 were constructed of aluminum while the remaining cars were constructed of double-skinned stainless steel. Cars 1 and 5 were 16.05 meters long, while the remaining cars were 13 meters long.
The set's traction system was very unique. The set used Toshiba insulated gate bipolar transistors as the traction system. However, instead of utilizing normal Cardan drive shaft traction motors, the E993 series used direct-drive motors, also manufactured by Toshiba. The use of direct-drive motors in the set gave it a very unique cadence when it accelerated from idle; once the set reached a certain speed, the traction motors made no discernible noise. Direct-drive motors were chosen to apparently reduce the sound from the set as it accelerated.
This direct-drive technology was also tested briefly on car MoHa 103-502 of Keiyō Line 103 series set KeYo304 from May 2002, with revenue service with the car inserted into the set commencing on 15 May 2003; the set was scrapped in December 2003 after just 7 months of service.
The E993 series set also had its direct-drive motors swapped out for Cardan drive shaft traction motors, in addition to using a different insulated gate bipolar transistor variable frequency drive traction system manufactured by Tōyō Denki Seizō which had a very distinctive, high-pitched cadence. When fitted with Cardan drive shaft motors, the E993 series sounded very much like most IGBT-fitted commuter trains, such as the E231 series.
Inside the train was an AIMS navigation system, an evolution of the older TIMS navigation system as used on various older sets, such as the E231 series. The E993 series also came with full-color front LED destination signage.
==References==
*Wikipedia.org
Category:Experimental locomotives
Category:Unique locomotives
Category:Electric trainsets
Category:JR Group trains
Category:Kawasaki locomotives
Category:Tokyu Car locomotives
Category:Scrapped locomotives
Category:Built in 2002