Twin unit

"Married pair" redirects here. For married human couples, see Marriage.

A twinset or twin unit is a set of two railroad cars or locomotives which are permanently coupled and treated as if they were a single unit. A twinset of cars or coaches can also be called a twin car.

USA

In US passenger railroad parlance, twin units are also known as Married pairs.^[1] On passenger railroads, light rail, and monorail services, married pairs may have machinery necessary for full operation of the cars split between them. Items that are typically shared include transformers, motor controllers, dynamic braking grids, cabs and current collectors. This provides significant savings in both cost of equipment and weight, which increases performance and decreases energy consumption. The cost is slightly higher operating costs incurred when the extra car of a pair is not necessary for the level of service.

See also

• Cow-calf
• Multiple unit

References

1. ^ Klein, Jonathan (1988). The economics of single vs. married-pair transit cars. Chicago Transit Authority. http://www.archive.org/details/economicsofsingl00klei.