What component is typically NOT present on both cars of a married pair?

In a married pair of train cars, a storage battery is typically not present on both cars. A married pair consists of two cars that are permanently coupled together to operate as a single unit. Generally, these cars share many systems to streamline operations and reduce redundancy. For instance, communication devices are often installed on both cars to maintain seamless communication between crew members on either car. Electrical circuits are usually designed to function across both cars as they often share electrical systems.

The brake handle, being part of the braking system, is also present on both cars to ensure that the train can be controlled effectively from either car. However, a storage battery, which serves as a power source for various electrical components, is not necessarily duplicated in a married pair. Instead, one of the cars may be equipped with the storage battery while the other relies on the first for power, thus eliminating the need for a second battery. This helps conserve space and reduce weight, optimizing the efficiency of the train car system.