The traffic countdown timer is independent of the road traffic lights and synchronously displays the remaining time of the traffic lights. The working principle is the remaining time display when the traffic signal is green or red. Fixed range display is the remaining time before the end of the green or red traffic signal.
The appearance requirements of traffic countdown timer are as follows:
1. The inner and outer surface of traffic countdown timer housing should be clean and smooth, shall be no dent, scratch, crack, deformation burr and other defects;
2. The housing surface of traffic countdown timer should be provided with firm anti rust and anti-corrosion plating (coating);
3. The rotating parts of traffic countdown timer should be flexible and the fastening parts shall not be loose;
4. The display unit and traffic countdown timer housing should be connected tightly without looseness. The display unit shall be sealed and the sealing surface shall be flat;
5. The door of traffic countdown timer cabinet should be easy to open, and the opening angle shall be greater than 80 °.
The requirements of traffic countdown timer for signs are as follows:
1. All signs, words, figures and symbols should be clear and eye-catching;
2. Each terminal on the terminal group should be identified according to the signal category, and the detailed meaning of the identification shall be explained in the user's manual. AC power line and grounding wire should be marked with standard symbols or words;
3. For electricity parts exceeding safety extra low voltage (AC peak value not exceeding 42.4v, DC voltage not exceeding 60V), eye-catching warning signs should be set at their prominent positions.