Tire pressure monitoring system is abbreviated as "TPMS", which is the abbreviation of "tire pressure monitoring system". This technology can automatically monitor various conditions of tires in real time by recording tire speed or electronic sensors installed in tires, which can provide effective safety guarantee for driving.
The tire pressure monitoring system can be divided into two types: one is the indirect tire pressure monitoring system, which judges whether the tire is abnormal by the difference in the rotation speed of the tire; the other is the direct tire pressure monitoring system, which is installed in the tire. A tire pressure monitoring sensor can automatically monitor tire pressure and temperature in real time when the car is stationary or driving, and provide timely alarms for tire high pressure, low pressure, and high temperature to avoid traffic accidents caused by tire failure to ensure driving safety.
Indirect tire pressure monitoring system
The indirect tire pressure monitoring system is also called WSBTPMS. WSBTPMS needs to compare the speed difference between tires through the wheel speed sensor of the car's ABS anti-lock braking system to achieve the purpose of monitoring tire pressure. ABS uses the wheel speed sensor to determine whether the wheels are locked, thereby deciding whether to activate the anti-lock braking system. When the tire pressure decreases, the weight of the vehicle will make the tire diameter smaller, and the vehicle speed will change. Changes in vehicle speed will trigger the WSB's alarm system to remind car owners to pay attention to insufficient tire pressure. Therefore, indirect TPMS is a passive TPMS.
Direct tire pressure monitoring system
The direct tire pressure monitoring system is also called PSBTPMS. PSBTPMS is a system that uses pressure sensors installed on the tires to measure the tire pressure and temperature, and uses wireless transmitters to send pressure information from the tires to the central receiver module. Display tire pressure data. When the tires appear high pressure, low pressure, high temperature, the system will give an alarm to remind the owner. And the car owner can set the tire pressure alarm value range and temperature alarm value by himself based on the car model, car usage habits, and geographic location. Therefore, direct TPMS belongs to active TPMS.
The direct system can provide more advanced functions. It can measure the actual instantaneous pressure inside each tire at any time, making it easy to determine the faulty tire. The cost of the indirect system is relatively low, and cars that have been equipped with 4-wheel ABS (each tire is equipped with a wheel speed sensor) only need to upgrade the software. However, the indirect system is not as accurate as the direct system. It cannot determine the faulty tire at all, and the system calibration is extremely complicated. In some cases, the system will not work normally, such as when the pressure of two tires on the same axle is low.
There is also a composite TPMS, which has the advantages of the above two systems. It is equipped with direct sensors in two diagonal tires and a 4-wheel indirect system. Compared with all direct systems, this composite system can reduce costs and overcome the shortcomings of indirect systems that cannot detect that multiple tires have low air pressure at the same time. However, it still cannot provide real-time data of the actual pressure in all four tires like a direct system.