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Phenolic Trimming Potentiometers Features

(Single Turn/ Phenolic/ Industrial)
(4 Terminal S tyles)

Phenolic Trimming Potentiometers Electrical Characteristics

Standard Resistance Range 100Ω - 2MΩ
Resistance Tolerance ±10%, ±20%, ±30%
Residual Resistance Max 5% of Nominnal Resistance, But under 30Ω
Pesistance Taper Linear (B)
Rated Power 0.1W
Operating Voltage 50V Max
Potational Life Max ±5% change in resistance after 100 unloaded rotations
Load Life Max ±5% change in resistance after 3 hours loaded

Phenolic Trimming Potentiometers Pictures

Related Articles:

Circularity Trimming Potentiometers

7 Terminal Square Trimming Potentiometers

Single-turn Trimming Potentiometers

Multi-turn Trimming Potentiometers

Circularity Trimming Potentiometer Features

(Single Turn/ Cermet/ Industrial/ Sealed)
(5 Terminal S tyles)

Circularity Trimming Potentiometers Electrical Characteristics

Standard Resistance Range 50Ω - 2MΩ
Resistance Tolerance ±5%, ±10%
Absolute Minimum Resistance ≤1% R or 2Ω
Contact Resistance Variation CRV≤3%or 3Ω
Insulation Resistance R1≥1GΩ(100Vac)
Withstand Voltage 500Vac
Effective Travel 280°

Circularity Trimming Potentiometer Pictures

Ceramic capacitors are constructed with materials such as titanium acid barium used as the dielectric. Internally, these capacitors are not constructed as a coil, so they can be used in high frequency applications. Typically, they are used in circuits which bypass high frequency signals to ground.

These capacitors have the shape of a disk. Their capacitance is comparatively small.

• The capacitor on the left is a 100pF capacitor with a diameter of about 3 mm.
• The capacitor on the right side is printed with 103, so 10 x 103pF becomes 0.01 µF. The diameter of the disk is about 6 mm.
• Ceramic capacitors have no polarity.
• Ceramic capacitors should not be used for analog circuits, because they can distort the signal.

The multilayer ceramic capacitor has a many-layered dielectric. These capacitors are small in size, and have good temperature and frequency characteristics.

Square wave signals used in digital circuits can have a comparatively high frequency component included.

This capacitor is used to bypass the high frequency to ground.

• In the photograph, the capacitance of the component on the left is displayed as 104. So, the capacitance is 10 x 104 pF = 0.1 µF. The thickness is 2 mm, the height is 3 mm, the width is 4 mm.
• The capacitor to the right has a capacitance of 103 (10 x 103 pF = 0.01 µF). The height is 4 mm, the diameter of the round part is 2 mm.
• These capacitors are not polarized. That is, they have no polarity.

In these devices, polystyrene film is used as the dielectric. This type of capacitor is not for use in high frequency circuits, because they are constructed like a coil inside. They are used well in filter circuits or timing circuits which run at several hundred KHz or less.

The component shown on the left has a red color due to the copper leaf used for the electrode. The silver color is due to the use of aluminum foil as the electrode.

• The device on the left has a height of 10 mm, is 5 mm thick, and is rated 100pF.
• The device in the middle has a height of 10 mm, 5.7 mm thickness, and is rated 1000pF.
• The device on the right has a height of 24 mm, is 10 mm thick, and is rated 10000pF.
• These devices have no polarity.

The invention of the capacitor varies somewhat depending on who you ask. There are records that indicate a German scientist named Ewald Georg von Kleist invented the capacitor in November 1745. Several months later Pieter van Musschenbroek, a Dutch professor at the University of Leyden came up with a very similar device in the form of the Leyden jar, which is typically credited as the first capacitor. Since Kleist didn't have detailed records and notes, nor the notoriety of his Dutch counterpart, he's often overlooked as a contributor to the capacitor's evolution. However, over the years, both have been given equal credit as it was established that their research was independent of each other and merely a scientific coincidence.

The Leyden jar was a very simple device. It consisted of a glass jar, half filled with water and lined inside and out with metal foil. The glass acted as the dielectric, although it was thought for a time that water was the key ingredient. There was usually a metal wire or chain driven through a cork in the top of the jar. The chain was then hooked to something that would deliver a charge, most likely a hand-cranked static generator. Once delivered, the jar would hold two equal but opposite charges in equilibrium until they were connected with a wire, producing a slight spark or shock.

Benjamin Franklin worked with the Leyden jar in his experiments with electricity and soon found that a flat piece of glass worked as well as the jar model, prompting him to develop the flat capacitor, or Franklin square. Years later, English chemist Michael Faraday would pioneer the first practical applications for the capacitor in trying to store unused electrons from his experiments. This led to the first usable capacitor, made from large oil barrels. Faraday's progress with capacitors is what eventually enabled us to deliver electric power over great distances. As a result of Faraday's achievements in the field of electricity, the unit of measurement for capacitors, or capacitance, became known as the farad.

For more information on capacitors and related topics, check out the links on the next page.

Electrolytic capacitors are polarised and they must be connected the correct way round, at least one of their leads will be marked + or -. They are not damaged by heat when soldering.

There are two designs of electrolytic capacitors; axial where the leads are attached to each end (220µF in picture) and radial where both leads are at the same end (10µF in picture). Radial capacitors tend to be a little smaller and they stand upright on the circuit board.

It is easy to find the value of electrolytic capacitors because they are clearly printed with their capacitance and voltage rating. The voltage rating can be quite low (6V for example) and it should always be checked when selecting an electrolytic capacitor. If the project parts list does not specify a voltage, choose a capacitor with a rating which is greater than the project's power supply voltage. 25V is a sensible minimum for most battery circuits.

Trimmer capacitors (trimmers) are miniature variable capacitors. They are designed to be mounted directly onto the circuit board and adjusted only when the circuit is built.

A small screwdriver or similar tool is required to adjust trimmers. The process of adjusting them requires patience because the presence of your hand and the tool will slightly change the capacitance of the circuit in the region of the trimmer!

Trimmer capacitors are only available with very small capacitances, normally less than 100pF. It is impossible to reduce their capacitance to zero, so they are usually specified by their minimum and maximum values, for example 2-10pF.

Trimmers are the capacitor equivalent of presets which are miniature variable resistors.

Trimming potentiometers perform a variety of circuit adjustments in all types of electronic equipment. The variety of physical configurations available and the ability to withstand today's manufacturing environment offers the designer flexibility in selecting the best trimmer for the application. Around the world, trimmers are used in virtually every electronic market.

Typical applications include measuring linear distance, angles or rotations in production equipment, industrial test and measurement equipment, and medical equipment.