Trimmer Potentiometers:

How do you adjust a trimmer potentiometer?

A trimmer resistor is a resistor that can be adjusted or “trimmed” to an exact resistance by turning a screw. This type of resistor is often used in circuits because it allows for adjustments in circuit performance. The adjustment is made by using a tool, such as a screwdriver, to turn the dial or knob on the device.

Trimmers are normally manufactured as single-turn or multi-turn components and may be top-adjusted or side-adjusted. Multi-turn trimmers can be used with automated test equipment (ATE) and are also available with anti-rotation features that prevent the adjustment from being changed accidentally.

Trimmer resistors are usually used in applications where adjustments need to be made during production, or where the effect of manufacturing tolerances needs to be compensated for during the operational life of a product.

Types of trimmer resistors

Single-turn Trimmer Resistors have a screw that turns about 300 degrees in either direction to adjust the resistance value. This type of resistor has a resistance range of 10Ω - 10MΩ and can be adjusted in increments as fine as 0.01Ω. It can handle up to 2.75W of power.

Multiturn Trimmer Resistors work like single-turn trimmers, except they have multiple turns—usually five and an adjustment range of 10Ω -5 MΩ. They can also be adjusted in fine increments, but they can only handle 1W of power, making them less powerful than single-turn trimmers.