How to determine the positive and negative terminals of a capacitor without a multimeter?
We usually use multimeters to measure values such as voltage, current, resistance, and capacitance. So how can we determine the positive and negative poles of a capacitor without a multimeter?
Some of our common capacitors have polarity, and some capacitors do not distinguish polarity.
1. Capacitors that do not distinguish polarity
Our most common CBB capacitors, ceramic capacitors, and polyester capacitors have no polarity distinction, so you don't need to pay attention to the polarity when using them.
2. Distinguish the polarity of capacitors
Solid capacitor. Solid capacitors can be distinguished according to the marking on the capacitor shell. The black edge on the shell is the negative pole, or the short capacitor pin is the negative pole.
Aluminum electrolytic capacitors. There will be a "-" symbol marked on the capacitor's shell, and the marked side is the negative pole.
When using capacitor as an important component of the circuit, be careful to select the correct capacitor parameters according to different characteristics. The distinction between positive and negative poles is generally based on these methods.
AC capacitors do not distinguish between positive and negative polarities. For example, single-phase motor starting capacitors, washing machine starting capacitors, electric fan starting capacitors, energy-saving lamp damping buck capacitors, etc. are all AC capacitors. They do not distinguish between positive and negative polarity. The common code is: ACxx microfarads, there is no need to distinguish between positive and negative poles. TVs, Dvs, cassette players, and energy-saving lamps use DC capacitors to output DC voltage after rectification of alternating current. It is often marked DCx × microfarads. Generally, the negative electrode shell is marked with "- Peugeot, this negative corresponds to the negative pole of the capacitor, and the other leg is the positive pole. You can see it at a glance without using a multimeter.
