How to distinguish the positive and negative poles of a cigarette lighter?
2 Answers
The center contact of a car cigarette lighter is the positive pole, while the outer contact plate is the negative pole. Below is relevant information about car cigarette lighters: 1. Working principle: In addition to lighting cigarettes, a car cigarette lighter can also be equipped with a vehicle inverter, which converts 12V, 24V, or 48V DC power from the car into 220V/50Hz AC power for use with ordinary electrical appliances. For example, it can charge mobile electronic devices. It is best to use a split-type vehicle inverter, with the power of the electrical appliance limited to below 150W, ensuring the output current does not exceed the battery current. 2. The power voltage of the cigarette lighter is 12 volts, consistent with the vehicle's battery voltage. Typically, the cigarette lighter has a separate power line connected to it and does not share circuits with other lines, thus having a separate fuse. The correct method of use is to insert and remove it vertically without shaking, as frequent shaking during removal can cause looseness and short circuits, burning out the fuse and external devices.
As a car owner with years of driving experience, I have expertise in identifying the positive and negative terminals of a cigarette lighter. The small metal pin in the center is the positive pole, while the outer metal ring is the negative. This design is quite common. If connected incorrectly, it may cause a short circuit, blow a fuse, or even damage the device. I often use a multimeter for testing: set it to DC voltage mode, touch the red probe to the center pin (positive), and the black probe to the outer ring (negative). A normal reading of around +12 volts indicates safety. The cigarette lighter socket is located in the central control area, originally designed for lighting cigarettes, but now more commonly used for plugging in chargers or air pumps. However, extra caution is needed when modifying wiring—though 12 volts is low, high current can still be dangerous. Once, a friend of mine reversed the wiring while DIY-installing a dashcam, causing sparks to fly. Fortunately, he turned it off in time. I recommend beginners use testing tools first and avoid rushing into hands-on work. Keeping the socket clean prevents oxidation and poor contact. Understanding these details makes driving safer and more worry-free.
