Traffic Light Installation and Its Quantity Requirements and Control

It is believed that we are familiar with traffic light, its existence makes the passing vehicles more orderly, which guarantees our traffic safety, and its installation has certain guidelines. The following describes its installation quantity and orientation rules:

Ⅰ. Requirements for the number of traffic signals

1. When the distance between the entry parking line and the opposite traffic signal light is greater than 50 meters, at least one group should be added at the entrance; when the distance between the entry parking line and the opposite signal is greater than 70 meters, the opposite light-emitting unit should be selected. The smooth surface size is φ400mm.

2. A certain group of traffic signal lights installed at the exit indicates more lanes, and when the indicated lane is not within the following three ranges from the parking line to the parking line, one or more groups should be added accordingly.

Ⅱ. Requirements for orientation of traffic signals

1. The orientation of the vehicle traffic signal lamp should be such that the reference axis is parallel to the ground, and the vertical plane of the reference axis passes through the center point 60 meters behind the parking line of the controlled motor vehicle lane.

2. The position of the non-motor vehicle signal lamp should be such that the reference axis is parallel to the ground, and the vertical plane of the reference axis passes through the center point of the parking line of the controlled non-motor vehicle lane.

3. The installation orientation of the pedestrian light controlled crossing should be such that the reference axis is parallel to the ground, and the vertical plane of the reference axis passes through the midpoint of the boundary line of the controlled crosswalk.

Ⅲ. How to complete the control of traffic signals

1. Punctual control

Intersection wireless traffic signal controllers all operate according to the timing plan set in advance, also called fixed-period control. Only one timing plan a day is called single-stage punctual control; a day that selects several timing plans according to the traffic volume at different times of the day is called multi-stage punctual control. The most fundamental control method is punctual control of a single intersection. Line control and surface control can also be used in punctual control, also called static line control system and static surface control system.

2. Inductive control

Inductive control is a control method in which a vehicle detector system is installed at the entrance of an intersection. The traffic signal timing plan is calculated by a computer or an intelligent signal controller, and can be changed at any time according to the traffic information detected by the detector. The fundamental method of induction control is induction control at a single intersection, referred to as single-point control induction control. Single-point sensing control can be divided into semi-sensing control and full sensing control depending on the detector setting method.