A complete six-car trainset consists of an identical twin set of one driving motor car (DM1), one trailer car (T) and one intermediate motor car (M2) permanently coupled together.

The configuration of a C301 trainset in revenue service is DM1–T–M2–M2–T–DM1.

Each car is assigned its own four-digit serial number, which ranges from x101 to x172.

The first digit (the 'x' above) indicates the position of the car.
Hence, DM1 cars use the number x=1, T cars x=2, and M2 cars x=3
The other three digits are the identification number of the train the car is part of.
A full-length train of six cars consists of two identification numbers, one for the first three cars, and another for the second three.
The bigger number is always equal to the smaller number plus one, and the smaller number is always an odd number.
For example, a train of six cars would have serial numbers 1101, 2101, 3101, 3102, 2102, and 1102, respectively.

Trainset number 117/118 was temporarily withdrawn from service following the 2014 Taipei Metro attack and underwent disinfection and change of seats.
It was then renumbered 175/176 (173/174 was avoided as the number "一七三, 一七四" sounded like "一起殺、一起死", which literally means "kill together, die together") and returned to service in 2015.
A complete six-car trainset consists of an identical twin set of one driving motor car (DM1), one trailer car (T) and one intermediate motor car (M2) permanently coupled together.
The configuration of a C301 trainset in revenue service is DM1–T–M2–M2–T–DM1.
Each car is assigned its own four-digit serial number, which ranges from x101 to x172.
The first digit (the 'x' above) indicates the position of the car. Hence, DM1 cars use the number x=1, T cars x=2, and M2 cars x=3
The other three digits are the identification number of the train the car is part of. A full-length train of six cars consists of two identification numbers, one for the first three cars, and another for the second three. The bigger number is always equal to the smaller number plus one, and the smaller number is always an odd number. For example, a train of six cars would have serial numbers 1101, 2101, 3101, 3102, 2102, and 1102, respectively.
Trainset number 117/118 was temporarily withdrawn from service following the 2014 Taipei Metro attack and underwent disinfection and change of seats. It was then renumbered 175/176 (173/174 was avoided as the number "一七三, 一七四" sounded like "一起殺、一起死", which literally means "kill together, die together") and returned to service in 2015.
Taipei Metro C321