Potentiometers

The possibilities of using a potentiometer are manifold. How and in which case depends on your application.

Guide for Potentiometers

Potentiometers

Conductive Plastic Potentiometers, Wirewound Potentiometers, Multiturn Potentiometers and Multiganged / Tandem Potentiometers

Not all potentiomerers are alike! Our portfolio contains only potentiometers with much more precise electrical and mechanical tolerances, significantly increased lifespan, higher reliability and component quality than conventional low-cost potentiometers: Namely precision potentiometers; and this for over 60 years.

Our considerable range of potentiometers is based on the most varied application possibilities. And yet it is not sufficient for all applications. In many cases, demanding applications require technical adaptation, which we implement even for relatively small quantities.

Within the scope of our consultation, we define together with you the optimal product for your "design in". Our claim is to provide each customer individually with the best functional and economical result. With high delivery reliability and assured quality products, we focus on long-term partnerships and accompany you throughout the entire life of your application.


54 results found
Conductive Plastic Potentiometer-MP20
Conductive Plastic Potentiometer MP20/21
Compact precision potentiometer with a long lifespan and many options
  • Long lifespan and high accuracy
  • With or without mechanical end stop (320° / 360°)
  • Compact sensor with low installation depth of 12 mm
Conductive Plastic Potentiometer-MP22_23
Conductive Plastic Potentiometer Series MP22/23
Conductive Plastic Potentiometer with high durability in Ø22 mm metal housing and low installation depth with axial connections
  • Long life and accuracy
  • With or without mechanical end stop
  • Compact sensor with low installation depth 12 mm
  • A potentiometer with many options
Conductive Plastic Potentiometer-MPA20_21
Conductive Plastic Potentiometer MPA20/21
Highly durable precision potentiometer in 22 mm housing
  • Highly accurate with a long lifespan and durability
  • With or without a mechanical end stop (320° / 360°)
Conductive Plastic Potentiometer-MPAS20_21
Conductive Plastic Potentiometer MPAS20
Highly durable servo flange-precision potentiometer in 22 mm housing
  • Highly durable and high accuracy
  • Servo flange for precise installation
  • 2 precision ball bearings
Conductive Plastic Potentiometer-MPS20_21
Conductive plastic potentiometer MPS20
Compact servo flange precision potentiometer with high durability and accuracy in 22 mm housing with precision ball bearings and radial connections
  • Long lifespan and accuracy
  • Servo flange with radial connections
  • Compact sensor
Conductive Plastic Hollow Shaft Potentiomter-MHP32
Conductive Plastic Potentiometer with hollow shaft MHP32
Conductive plastic hollow-shaft potentiometer with backlash-free coupling for convenient installation
  • High quality conductive plastic element and multi-finger slider    
  • Compact, space-saving housing design (ø32 x 8 mm)
  • Fast and easy installation
  • Easy, back-lash free coupling
Conductive Plastic Hollow Shaft Potentiometer MHP24
Hollow-shaft conductive plastic potentiometer MHP24
Very compact hollow-shaft potentiometer with a precious metal wiper suitable for very confined spaces
  • Space-saving flat housing (Ø24 x 7.1 mm)
  • Simple mounting on flatted hollow shaft hub and anti rotation pin
  • Conductive plastic and high-quality multi finger wiper (precious metals) gives a reliable signal output
Conductive Plastic potentiometer-MCP05
Conductive Plastic Potentiometer MCP05
Precisely mountable miniature potentiometer with servo flange, ball bearing and long lifetime in 13 mm housing
  • Miniature housing with Ø13 mm
  • Ideal for confined spaces
  • Servo flange for exact assembly
  • 2 precision ball bearings
  • Optional back shaft
Conductive Plastic potentiometer-MCP22
Conductive Plastic Potentiometer MCP22
High-resolution precision potentiometer in 22 mm housing with servo flange, good linearity and excellent lifetime
  • Very long life span
  • Very precise sensor
  • Servo flange for precise mounting
  • 2 Precision ball bearings
  • Robust metal housing
Conductive Plastic potentiometer-MCP30
Conductive Plastic Potentiometer MCP30
High-resolution precision potentiometer with servo flange, good linearity and excellent lifetime
  • Very long life
  • Very precise sensor
  • Servo flange for precise mounting
  • 2 Precision ball bearings
  • Robust metal housing
Conductive Plastic potentiometer MCP40
Conductive Plastic Potentiometer MCP40
High-resolution precision potentiometer with servo flange, excellent linearity and lifetime and high resistance value
  • Very long life
  • Extremely precise sensor
  • Servo flange for precise mounting
  • 2 Precision ball bearings
  • Robust steel housing
  • Energy saving in applications
Conductive Plastic Potentiometer-MCP50
Conductive Plastic Potentiometer MCP50
High resolution precision potentiometer with excellent linearity and lifetime, very high resistance value and high electrically effective rotation angle
  • Very long life
  • Extremely precise sensor
  • Servo flange for precise mounting
  • 2 Precision ball bearings
  • Robust metal housing
  • High max. resistance
  • Very energy saving in applications
  • Very high electrically effective rotation angle 350° ±5°
Conductive Plastic Potentiometer-MFP500
Conductive Plastic Potentiometer MFP500
Servo flange potentiometers in rugged IP65 industrial design and very long life span
  • Very long life span
  • Extremely precise sensor
  • 2 x ball bearings
  • Servo flange for precise installation
  • Robust metal housing
  • Very high electrically effective angle of rotation 355° ±2 °
Conductive Plastic Potentiometer-MP10_11
Conductive Plastic Potentiometer MP10/11
Durable miniature precision potentiometer in Ø13 mm metal housing with optional rear shaft
  • Miniature housing with Ø13 mm
  • Ideal for confined spaces
  • With or without mechanical end stop (310° / 360°)
  • Lifespan 5 million movements
  • Robust metal housing
  • Optional back facing shaft
Conductive Plastic Potentiometer-SFCP22
Conductive plastic potentiometer SFCP22
Robust servo flange potentiometer in 22 mm metal housing with very long lifespan
  • Very long lifespan 20 mio. rotations
  • High accuracy
  • Compact sensor
  • 2 x ball bearings
  • Optional rear shaft, center tap
Wirewound Potentiometer-RP19_20
Wirewound potentiometer RP19/20
Compact precision potentiometer with good accuracy and high electrically effective rotation angle in 22 mm housing
  • Accurate wirewound potentiometer
  • With or without mechanical end stop (320° / 360°)
  • Very high electrically effective angle of rotation 355° ±5°
  • Compact sensor with 12 mm installation depth
  • With many options
Wirewound potentiometer-RP22_23
Wirewound potentiometer RP22/23
Compact and very accurate potentiometer in 22 mm rugged metal housing. RP22 with high electrically effective rotation angle. RP23 with end stop
  • Accurate wirewound potentiometer
  • With or without mechanical end stop (320° / 360°)
  • Very high electrically effective angle of rotation 355° ±5°
  • Compact sensor with 12 mm installation depth
  • With many options
Wirewound Potentiometer MUP
Wirewound potentiometer MUP
Compact, economical and universal wirewound potentiometer in 22 mm housing
  • Economical and universal potentiometer
  • Compact with only 8.6 mm housing depth
  • With mechanical end stop (320° / 270°)
  • A potentiometer with many options
Wirewound potentiometer-RPS45
Singleturn-Wirewound Potentiometer RPS45
Precise wirewound potentiometer with high angular resolution in Ø41 mm servo flange housing and many options
  • Accurate wirewound potentiometer
  • Very high electrically effective angle of rotation 355° ±3°
  • On request with mech. end stop (330°)
  • Multi-ganged up to 7 gangs
  • With many options
Wirewound potentiometer-RPS50
Singleturn wirewound potentiometer RPS50
Very accurate wirewound potentiometer with high angular resolution in Ø50 mm servo flange housing and many options
  • Very accurate wirewound potentiometer
  • Very high electrically effective angle of rotation 355° ±3°
  • On request with mech. end stop (330°)
  • Multi-ganged up to 7 gangs
  • With many options
  • On request with spring return (automatically returning to the zero position)
Wirewound potentiometer-S11
Singleturn Wirewound Potentiometer S11
Wirewound potentiometer with high electrically effective angle of rotation in Ø22 mm servo flange housing
  • High electrically effective angle of rotation 355° ±3°
  • On request with mechanical end stop (330°)
  • Multigang-capable up to 5 gangs
Wirewound potentiometer-S12
Singleturn Wirewound Potentiometer S12
Wirewound potentiometer with high electrically effective angle of rotation in Ø27 mm servo flange housing
  • High electrically effective angle of rotation 355° ±5°
  • On request with mechanical end stop (330°)
  • Multigang-capable up to 5 gangs
Multiturn Rotary Potentiometer-AL9
Miniature rotary potentiometer AL9
Miniaturized, economical and precise multi-turn rotary potentiometer for moderate operations
  • Miniaturized and economical manual adjuster
  • Precise 10-turn rotary potentiometer
  • With axial or radial connections
  • Versions for direct PCB mounting
Multiturn Wirewound Potentiometer-AL17_19
Multiturn Wirewound Potentiometer AL17/19
Economical multiturn potentiometer with high precision in 22 mm housing and many options
  • Economical and precise multiturn potentiometer
  • Version with integrated connector
  • Version ALR17/19 with integrated slipping clutch
  • Potentiometer with many options
Multiturn Wirewound Potentiometer ALIR17_19
Multiturn Wirewound Potentiometer ALI17/19
Robust multiturn potentiometer for increased radial shaft loads in 22 mm housing
  • Multiturn potentiometer
  • Robust design for radial shaft load up to 4N
  • With optional integrated slipping clutch
  • Connector version simplifies the mounting
Wirewound Mutliturn Potentiometer AC
Multiturn-Wirewound Potentiometer AC
Robust multi-turn potentiometer with high precision in 20 mm housing and many options
  • Economical and precise multiturn sensor with numerous options
  • Completely encapsulated housing with 2 x sleeve bearings
  • With many options
Multiturn-Wirewound potentiometer-Series-21
Multiturn-Wirewound Potentiometer Series 21
Precise multiturn wirewound potentiometer in 20 mm servo flange housing and 2 x ball bearings
  • Servo flange for precise installation
  • 2 precision ball bearings
  • On request with limit switch 
Wirewound Potentiometer-Multiturn SMT
Multiturn-Wirewound Potentiometer SMT
The Smallest 10-turn potentiometer in the world
  • The Smallest 10-turn potentiometer in the world
  • Only Ø10.5 mm
  • 5 or 10 turn versions
Miniature-Wirewound-Multiturn-Potentiometer-AL10
Miniature wirewound multiturn potentiometer AL10
Miniaturized and precise multiturn potentiometer in Ø13 mm housing optionally for PCB mounting
  • Miniaturized and precise 10-turn potentiometer
  • Versions for direct PCB mounting
  • ≥ 2 million revolutions
Potentiometer-Wirewound Multiturn-HS17
Multiturn Wirewound Potentiometer HS17
Economical and high precision multiturn potentiometer in 22 mm servo flange housing and many options
  • Optional version HS17xxR with integrated slipping clutch
  • With many options
Multiturn-Wirewound potentiometer AL13
Multiturn Wirewound Potentiometer AL13
Very compact multiturn wirewound potentiometer in Ø13 mm servo flange housing
  • Miniaturized and precise 10-turn potentiometer
  • 2 x ball bearings
  • ≥ 2 million revolutions
Wirewound potentiometer-Multiturn-46
Multiturn-Wirewound Potentiometer Series 46
Potentiometer with up to 30 turns and power rating up to 10 W in 46 mm housing
  • Multiturn 3…30 turns
  • Optional limit switch (CW, CCW)
  • Optional back shaft
  • Power rating up to 10 W
  • Optional tandem version
Multiturn-Wirewound-Potentiometer-S46HDS
Multiturn-Wirewound Potentiometer 46HDS
Servo flange potentiometer with up to 20 turns and power rating up to 10 W in 46 mm housing
  • Multiturn 3…20 turns
  • Optional limit switch (CW, CCW)
  • Optional back shaft
  • Power rating up to 10 W
  • Optional tandem version
Wirewound Multiturn Potentiometer-AL20
Multiturn-Wirewound Potentiometer AL20
Robust multi-turn potentiometer with high precision in 20 mm housing without pilot ring
  • Economical and precise multiturn sensor with numerous options
  • Completely encapsulated housing with 2 x sleeve bearings
  • Without pilot ring
Multiturn Wirewound Potentiometer-AL25
Multiturn-Wirewound Potentiometer AL25
Potentiometers with outstanding linearity and resolution for measuring ranges from 3 to 20 revolutions in 25 mm housing
  • Multiturn 3…20 turns
  • Optional limit switch (CW, CCW)
  • Optional rear shaft
  • Optional tandem version
Multiturn-Wirewound-Potentiometer-AL25S
Multiturn wirewound potentiometer ALS25
Potentiometers with outstanding linearity and resolution for measuring ranges from 3 to 20 revolutions in Ø25 mm servo flange housing
  • Multiturn 3…20 turns
  • On request limit switch (CW, CCW)
  • Optional rear shaft
  • Optional tandem version
Rotary Potentiometer with knob-MD22 black
Multiturn Rotary Potentiometer with Knob MD22
Completely pre-assembled set, with 3-digits, button in two colors - ready for installation on the front panel
  • Completely pre-assembled set
  • 000...999 good readability of the digits
  • Knob in grey or black
  • Versions with IP65 over the front panel
  • Soldering lugs or clamp connection
  • With many options
Rotary Potentiometer with knob-MD32
Multiturn Rotary Potentiometer with Knob MD32
Completely pre-assembled set, with locking mechanism, 3-digits, button in two colors - ready for installation on the front panel
  • Completely pre-assembled set
  • 000...999 good readability of the numbers
  • Knob in grey or black with locking mechanism
  • Soldering lugs or clamp connection
  • With many options
Rotary Potentiometer with Knob MCD17
Multiturn Rotary Potentiometer with Knob MCD17
Completely pre-assembled set, with locking mechanism, 3-digits - ready for installation on the front panel
  • Completely pre-assembled set
  • 000...999 good readability of the numbers
  • Knob with locking mechanism
  • Soldering lugs or clamp connection
  • With many options
Miniature-Wirewound-Multiturn-Potentiometer-AL10
Miniature multiturn hybrid potentiometer AL11
Miniaturized and precise multiturn potentiometer in 13 mm housing with long life and low signal noise
  • Miniaturized and precise 10-turn potentiometer
  • Versions for direct PCB mounting
  • ≥ 10 million revolutions and low signal noise (hybrid technology)
Hybrid potentiometer AL14
Multiturn-Hybrid-Potentiometer AL14
Very compact and accurate multiturn potentiometer with long life span in 13 mm housing
  • Very precise potentiometer
  • Long lifespan
  • Compact construction
Multiturn-Wirewound Potentiometer-AL24
Hybrid potentiometer AL24
High-resolution and long-lasting multi-turn potentiometer with very low signal noise in 20 mm housing
  • Very high-resolution and long-lasting due to hybrid technology
  • Very clean signal - no winding jumps thanks to hybrid technology
Multiturn Wirewound Potentiometer-AL17_19
Multiturn Hybrid Potentiometer HH17/19
High-resolution and long-lasting multiturn potentiometer with very low signal noise in 22 mm housing
  • Very high-resolution and long-lasting due to hybrid technology
  • Very clean signal - no winding jumps thanks to hybrid technology
  • Simplified installation due to connector version
  • Version HHR17/19 with integrated slipping clutch
Multiturn Wirewound Potentiometer ALIR17_19
Multiturn Hybrid Potentiometer HHI17/19
High-resolution and long-lasting potentiometer in 22 mm housing, optimized for radial shaft load
  • Very high-resolution, long-lasting and clean signal
  • Robust due to reinforced bearing - up to 4 N
  • Simplified mounting due to connector
  • Version HHIR17/19 with slipping clutch
  • With many options
Potentiometer-Hybrid-HHS17
Multiturn hybrid potentiometer HHS17
High-resolution and long-lasting multiturn potentiometer with very low signal noise in 22 mm servo flange housing
  • Very high-resolution, long-lasting and clean signal
  • No winding jumps due to hybrid technology
  • Optional version HHS17xxR with slipping clutch
  • With many options
Hybrid-Potentiometer-HH21
Mulitturn-Hybrid Potentiometer HH21
High-resolution and long-lasting multi-turn potentiometer with very low signal noise in 20 mm servo flange housing and 2 x ball bearings
  • Very high-resolution and long-lasting due to hybrid technology
  • Very clean signal - no winding jumps thanks to hybrid technology
  • 2 x ball bearings
Wirewound potentiometer-oilfilled-OF30
Singleturn wirewound oil-filled potentiometer OF30
Oil-filled wirewound potentiometer in Ø32 mm housing with or without mechanical stop
  • Oil-filled potentiometer
  • Optional center tap
  • Optional with mech. stop @300°
Multiturn-Wirewound potentiometer-oilfilled-OF50
Multiturn wirewound oil-filled potentiometer OF50
Oil-filled and multigangable wirewound potentiometer in Ø62 mm housing with optional limit switch, rear shaft and mech. stop
  • Oil-filled potentiometer
  • Optional tandem version
  • Optional rear shaft
  • On request with limit switch
Wirewound potentiometer oilfilled OF5001
Singleturn wirewound oil-filled potentiometer OF5001
Oil-filled wirewound potentiometer in Ø62 mm housing with or without mechanical stop
  • Oil-filled potentiometer
  • Optional center tap
  • Optional without mech. stop
  • Optional tandem version
  • Optional rear shaft
Hybrid potentiometer-oilfilled-OFH
Multiturn hybrid potentiometer oil-filled OFH
Oil-filled and precise hybrid potentiometer OFH with long life span in Ø32 mm housing
  • Oil-filled potentiometer
  • Long lifespan
  • Optional center tap
Conductive Plastic potentiometer-oilfilled-OMCP
Oil-filled Conductiv Plastic Potentiometer OMCP
Oil-filled conductive plastic potentiometer in Ø32 mm housing with high durability
  • Oil-filled conductive plastic potentiometer
  • Very high lifespan
  • Optional center tap
Conductive Plastic Potentiometer-SCX22
SIN-COS Potentiometer SCX22
Compact non-linear potentiometer in Ø22 mm metal housing with very long lifespan and opt. rear shaft
  • Precise sinus cosines potentiometer in 22 mm housing
  • Very long lifespan
  • 2 x ball bearings
  • Effective electrically angle of rotation 360°
Conductive Plastic Potentiometer-SCX30
SIN-COS Potentiometer SCX30
Precise non-linear potentiometer in Ø27 mm metal housing with very long lifespan and opt. rear shaft
  • Very precise sinus cosines potentiometer
  • High resistance versions
  • Very long lifespan
  • 2 x ball bearings
  • Electrically effective angle of rotation 360°
Conductive Plastic Potentiometer-SCX50
SIN-COS Potentiometer SCX50
Very precise non-linear potentiometer in Ø51 mm metal housing with very long lifespan and opt. rear shaft
  • Very precise sinus cosines potentiometer
  • Power rating up to 1,25 W
  • Very high resistance versions
  • Very long lifespan
  • 2 x ball bearings
  • Electrically effective angle of rotation 360 °
Guide for Potentiometers
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Potentiometers field of application

Potentiometers are long-established sensors. They are popular because of their easy integration into the application, their power consumption is low, and the signal is immediately available without computing time. Above all,  they have proven themselves over a long period of time, and their mode of operation is well known. Basically, potentiometers are used wherever angles or positions need to be measured. The large number of potentiometer types and their variants cover a very broad application landscape. Even within one particular potentiometer technology the variety of properties and options is broad. It therefore always depends on the respective application whether the potentiometer is suitable for the intended task.

As a general rule, potentiometers

  • are not suitable for high mechanical shock loads 
  • nor for high adjustment speeds >400 rpm, but are considered
  • insensitive to EMC influences and
  • insensitive to ESD influences

because they are passive components.


What is a potentiometer?

The potentiometer was invented by Johann Christian Poggendorf in 1841. It has been used as an input element and sensor since the beginning of the commercial use in electrical engineering. In principle, the design and function of all "potentiometers" are the same. They have a so-called resistance element with a movable wiper contact, which taps a voltage potential on a resistance track. Potentiometers are therefore variable voltage dividers. The resistive element of rotary potentiometers is circular. For connection to the application, rotary potentiometers have a mechanical connection (usually a shaft) and electrical connections (usually three).


Electrical connection and signal output of potentiometers

Potentiometers usually have three connections: Two for the resistance element and one for the wiper (signal output). If one follows a usual connection diagram for a potentiometer and applies 0 V to the defined connection "one", 5 V to the connection "three" and turns the shaft of the potentiometer, a voltage signal of 0 to 5 V is "output" via connection "two" (on the wiper). An absolute analogue signal is immediately available without any switch-on delay and computing times.

The value of the signal output depends on the applied voltage in relation to the position of the wiper on the resistance track. By changing the position by means of a rotational movement and direction of rotation, a voltage difference between position A and position B can be detected and thus the position can be determined in angular degrees.
    
Our potentiometers provide almost exclusively a linear output signal. Exceptions are our sine/cosine potentiometers.

The angular position of rotary potentiometers can be easily determined using the formula below:

\(θ = \frac {Vout} {Vin} * \text{electrically effective angle of rotation}\)

Example: \(θ = \frac {4} {5} * 320° \approx272°\)

If approx. 4 V is measured at the wiper with a total angle of 0° to 340° and a voltage range of 0 to 5 V, this would correspond to an angle of approx. 272°. However, this is a theoretical value, since potentiometers have different values for hysteresis and linearity tolerance depending on their design.


Potentiometer technologies

Our precision potentiometers are available in three different resistance elements (technologies). The respective resistance element is largely responsible for the quality and function of the application.

Wirewound Potentiometer

  • In principle, they can also be used as variable resistors (in a so-called rheostat circuit). However, we recommend the voltage divider circuit, as the components are designed for this purpose.
  • Available in so-called single-turn (<360°) and multi-turn (>7200°) versions.
  • They have a limited lifespan due to wear and tear and due to the winding jumps of the wire windings "steps" in the output signal, which manifest themselves as noise when the wiper moves.

Conductive plastic and hybrid potentiometer

  • Both technologies must never be used as variable resistors (rheostat circuit), but only in the voltage divider circuit
  • Conductive plastic is only available as single-turn and hybrid only as multiturn variants
  • Hybrid potentiometers make it possible to use the advantages of conductive plastic potentiometers also for multiturn potentiometers
  • They have a significantly longer lifespan because the resistance track is very smooth, they have a theoretically infinite resolution, a particularly smooth output signal, outstanding linearity and allow higher adjustment speeds

Resistance elements in comparison

Resistive elementConductive PlasticWirewoundHybrid
Lifespan++0+
Signal quality / resolution+++++++
Linearity++++++++
Electrical travelmax. 360°10800°max. 3600°
Operational speed++-+
Max. wiper current--+--
Shock / Vibration-----

Legend: +++ best | ++ very good | + good | 0 OK | - low | -- unfavourable | --- not appropriate


Multiganged / Tandem Potentiometer

If redundancy of the sensor technology is required in applications, so-called multiganged potentiometers or tandem potentiometers in double version are often used. The overview of all multiganged potentiometers can be found here.
The field of application ranges from mechanical engineering to aviation. To ensure that the tight linearity tolerances of the potentiometers maintain their quality, it is important to ensure that the heat generated during operation does not have a negative effect on the properties of the potentiometer due to the adjacent design. It is therefore necessary to reduce the nominal load according to the table.

These specifications/measured values apply under standard conditions (+15 °C to +35 °C). If the potentiometers are used at higher temperatures, the load must be reduced.

Multiganged Potentiometer AL17/19

*This graph does not apply to the oil-filled potentiometers.


Oil-filled potentiometers

Oil-filled potentiometers are usually employed in special application environments where, for example, aggressive gases, harmful salts or moisture can be a problem. These potentiometers are also characterized by the fact that the wiper contact resistance is particularly stable over the entire lifespan, as the oil filling suppresses corrosion at or near the wiper.
Some applications of these potentiometers are e.g. control systems in areas such as shipbuilding, electrical installations on the coast, pits and mines, ironworks, chemical plants, unmanned underground installations and machine tools.  However, some applications may require additional approvals, such as explosion protection, which must be obtained separately for each application.
The overview of all oil-filled potentiometers can be found here.

OF50 - oil-filled


Measuring amplifier / signal converter for potentiometer

As passive components, potentiometers do not offer standardized output levels such as 0..10 V, 4..20 mA. Please note that the output signal of the potentiometers should be tapped by means of a voltage divider circuit and thus virtually no current flows via the output. Using the signal itself as a voltage or current source for a converter is therefore not necessary. In order to generate standardized signals in a simple design, we offer measuring amplifiers that allow standardized signals to be obtained by means of an external power supply.


Circuit types

Voltage divider circuit

Operate the potentiometer in the voltage divider circuit and limit the wiper current to a minimum. Only in this way will the potentiometer retain its optimum lifetime characteristics and optimum signal quality.

  • The tolerance of the total resistance is not relevant
  • The temperature influences are almost completely suppressed

The voltage divider circuit offers the advantage of high robustness against parasitic resistances between resistor element and wiper. Only in the voltage divider circuit can you take full advantage of the special design features of each potentiometer type depending on the application.

Rheostat circuit

Do not operate the potentiometer in two-wire technology, as a variable resistor or rheostat. This type of circuitry has considerable disadvantages with regard to signal quality and lifespan of the potentiometer and is only possible for wirewound potentiometers (at low load). Conductive plastic and hybrid potentiometers are damaged in this type of circuit!


Total resistance

A high total resistance is advantageous in applications where low power is required. A low total resistance is advantageous in applications requiring "optimum" signal quality.

  • 500k potentiometer - for very low power applications
  • 100k potentiometer - often for battery powered applications
  • 10k potentiometer - standard applications

Center Tap

With this option you have the possibility to use an additional tap on the resistor track, which is realized as center tap at half resistance value corresponding to 50% of the electrical angle of rotation. This makes it possible, for example, to operate the potentiometer bipolar, i.e. to apply positive and negative voltage to the terminals of the resistance element (terminals 1 and 3), while the center tap is connected to ground. The center tap is for applications which ensure that the voltage value remains the same in the center position of the potentiometer throughout the life of the potentiometer, or if the output value is to be divided into two ranges. Please note that there are two possible implementations of this tap:

Voltage tap and current tap

Voltage tap

The voltage tap cannot take a load. Therefore, no current should flow over the center tap, otherwise the component is destroyed.

The following applies to the circuitry of the voltage tap: If the center tap is connected to ground and the end taps are both at negative and positive potential, currents should be prevented from flowing via the center tap by connecting an operational amplifier.
If only voltage of one polarity is applied from one end to the tap connected to ground, a too large current will flow at the intermediate tap. In this case, the voltage applied between terminals 1 and 3 must in any case be reduced below 50% of the rated voltage (less than 10% is recommended).

Current tap

The current tap influences the linearity of the component to a certain extent. Please contact us directly for more information about the sensor's characteristics regarding this special connection.
Joysticks are an example application for current taps: For a voltage range of 0 to 5 V within the travel range, the Center Tap is 2.5 V, which corresponds to non-actuation. Even when certain areas of the resistor track are worn out, the value at center tap always remains 2.5 V and no "wrong" output signals are generated. Here current taps are used throughout, because a certain current flow over the center tap can be expected.


Environmental influences

Vibration and shock effects
In general, it is recommended to avoid the effects of vibrations and shocks on potentiometers. Depending on the strength and frequency of these influences, the wiper can "lift off" from the resistor track, resulting in signal loss at these moments. In addition, these influences lead to increased wear on the resistor track, which results in losses in signal quality and decreased lifespan. Wirewound potentiometers are somewhat more robust and more suitable for low frequency applications than conductive plastic potentiometers.

Temperature influences
Our potentiometers are specified under standard conditions at room temperature (+15 °C to +35 °C). Lower or higher temperatures can influence the signal quality, for example by freezing humidity in the air or by evaporating grease and laying on the resistor track. Furthermore, the temperature influences the operating torque.
The use of appropriate seals or special greases can help. We would be pleased to support you with the appropriate requirements for your application.

EMC/ESD compatibility
Potentiometers are analogue, "passive" components that do not contain any electronics that could restrict the EMC or ESD properties. Potentiometers are therefore considered insensitive to electromagnetic interference, which is a great advantage in critical applications.


IP protection class

Nearly all our potentiometers are specified with protection class IP40 and nearly all of them can be increased to protection class IP65 with a shaft sealing ring on the shaft side. If a higher degree of protection is required, e.g. for the housing, the MFP500 and AL17IP (OFH, OF5001, OF30, OF50) fulfil this requirement. For many potentiometer series there are options available which allow a sealed housing.

First Digit: Solid particle protection
IP Degree of protection
0 Non-protected
1 ≥ 50 mm
2 ≥ 12.5 mm
3 ≥ 2.5 mm
4 ≥ 1 mm
5 Dust
6 Dust-tight
Second Digit: Liquid ingress protection
IP Degree of protection
0 Non-protected
1 dripping waters
2 dripping water when tilted at 15°
3 spraying water
4 splashing of water
5 water jets
6 powerful water jets
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Shaft torque

Our potentiometers are offered with precision ball bearings or sleeve bearings. In general, potentiometers with precision ball bearings have a lower torque than potentiometers with sleeve bearings. Servo flanged potentiometers are in principle always equipped with ball bearings. For almost all potentiometers it is possible to change the operating torque (e.g. 2 to 3 Ncm @ room temperature). In addition to the pleasant haptic properties, an increased rotational resistance prevents unintentional adjustment due to machine vibrations. A wide range of pre-assembled sets and adjustment knobs are available for your application. See rotary potentiometers


Mechanical stops & slipping clutch

Mechanical stops
In most cases the mechanical end stop is used for applications for manual setpoint setting. Please note the maximum permissible end stop torque and that all multiturn potentiometers have a mechanical end stop.
For potentiometers without a mechanical stop, a voltage fluctuation occurs when the ends are over-turned. Do not use the output signals of this end range as useful signals.

Slipping clutch
Slipping clutches are used with our multiturn potentiometers. The main purpose of the slipping clutch is to protect the mechanical stop from damage. However, if the clutch is permanently stressed, it can wear out more quickly and its lifespan is shortened. Please consider this effect.


Operating notes

Applications with very rare actuations
According to the motto "resting is rusting", the slider behaves in relation to the resistance track. Oxide/sulphide deposits can form. Please contact us to take suitable countermeasures in advance. For example, an increased contact pressure for the slider or appropriate seals promise to help.

Applications with very short continuous actuations
Please note that if the actuation travel is always the same and at the same time very short, the resistance element will experience increased wear at this point and the lifespan will be reduced. At the same time, microscopically small abrasion mounds are formed on the resistance element at the actuation ends, which influences the signal quality. Periodically passing over these points can clean the resistor track.


Shaft load & tightening torques

Tightening torques for threads and screws
Please take note of the tightening torques as well as dimensions for threads and screws to avoid damaging the potentiometer. Especially for potentiometers with a bushing, the torque of the shaft can be increased if mounted improperly. For mounting the servo flange potentiometers, corresponding synchro clamps are included in the delivery.

Mechanical coupling
Do not subject the shaft to excessive axial and radial loads in the long term. Normally, values of < 1 N do not pose a problem. Some potentiometers have a reinforced shaft bearing and allow values with < 4 N (e.g. ALI17/19). Use a shaft coupling to minimize existing shear loads (axial and radial loads).
When installing additional components such as shaft coupling, gear wheels or similar, please ensure that the shaft is not permanently loaded with more than 10 N. Short-term loads of this magnitude are no problem.


Adjustment, mounting types and soldering instructions

Zero point adjustment
The zero point adjustment can be conveniently made with a screwdriver slot on the shaft. The possibility of integrating a screwdriver slot on the shaft exists for all series with shaft and is already implemented as standard for some of them. For potentiometers with servo flange, zero adjustment is possible by simply turning the potentiometer housing. For this purpose, the synchro clamps must be loosened first.

Soldering note
Use a soldering iron with max. 60 W (<350 °C) for soldering the connections and do not contact with them more than three seconds.

Installation types
For panel mounting, the potentiometer with shaft must be mounted in a precisely machined hole without play. For potentiometers with a fixing pin, the so-called anti-rotation pin, please include a corresponding drill hole.
With hollow shaft potentiometers, a rigid fixing of the housing must be avoided. This is because the hollow shaft is not suitable to take over the bearing function of the actuating shaft.

The specifications in the data sheet for housing depth and housing diameter do not take into account the dimensions of the electrical connections. If the installation space is limited, please take into account above all the alignment of the connections and the additional space required for these.


Frequency Effect

Use in high frequency technology
Due to the mechanical construction, especially of multiturn potentiometers (wire winding), potentiometers have different values for inductance and capacitance, which must be taken into account in circuits of high frequency technology. These properties lead to phase shifts between current and voltage as well as to damping effects. However, in wirewound potentiometers (also hybrid potentiometers) these effects typically only occur at frequencies above 20 kHz. With conductive plastic potentiometers, these effects are negligible up to about 200 kHz, as there is no winding.


Product customizations

For over 60 years MEGATRON has been a reliable partner for your design-in. In addition to the wide range of options available for our sensors, we offer specific designs which exactly meet your application requirements, even in small quantities. Whether it is a prototype project or a series production - we are happy to support you.

Adjustment and option overview for potentiometers - a selection!

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