A varistor is a resistor with a nonlinear voltage-current characteristic, made from semiconductor resistor materials. Its resistance is sensitive to voltage changes within a certain range of current and voltage.
Its role is to clamp voltage in the circuit when subjected to overvoltage, absorbing excess current to protect other components. It can also provide protection against lightning and suppress surge currents, among other functions. In English, it is called a “Voltage Dependent Resistor,” abbreviated as “VDR,” or simply “Varistor.”
Varistors are typically made as round, blue disks. In addition to the common blue color, varistors are also available in other colors such as yellow, black, green, orange, and red.
So, why do varistors come in different colors? Does the working principle and function of varistors with different colors differ?
In reality, the different colors of varistors are not indicative of differences in their working principles or functions. The color of a varistor does not signify a specific functionality or working principle difference. Instead, it primarily serves as a means to identify and differentiate various types of varistors.
In China, there are many manufacturers of varistors. To make their products stand out and highlight their uniqueness among similar-colored products, different manufacturers may choose colors other than blue to distinguish their varistors. For example, one manufacturer may opt to use blue to represent a particular varistor model, while another may choose red or green, among other colors.
This article is provided by JYH HSU Electronics (JEC), a manufacturer of capacitors and resistors.
Post time: Oct-23-2023