The VL80S (ru: ВЛ80с) is simply a VL80T which has been modified for use in MU operations. The 'S' in its name derives from the first letter of the Russian term for multiple-unit train control: Система Многих Единиц (literally: Multiple Unit System) and commonly shortened to СМЕ.
The first VL80Ss to roll off the production line were designed to work with only two or four coupled units (or sections). In 1982, unit numbers 550, 551, and 552 were built to work with sets of two, three, or four sections. All VL80Ss built since 1983 (ВЛ80с-697 being the first of these) have this capability. The only restriction is that the consist cannot be a third trailer section equipped with dynamic brakes.
As a result of several modifications being made to the locomotive's construction, enabling it to pull additional units, the new certified weight became 192 tonnes.
A total of 2,746 examples rolled out of the NEVZ works between 1979 and 1994.
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