Nidec Copal J Series Single-turn Wirewound Potentiometer

Precision wire winding technology has been used to achieve low noise and long life. Wirewound types include the single turn J series for use in servo drives and the multiturn M series for use in setting.


Potentiometers are displacement sensors that produce electrical output (voltage) in proportion to the mechanical displacement. They are basically composed of a resistor and a wiper (brush), with the mechanical displacement of the resistor relative to the wiper being accurately converted into electrical voltage output. A voltage is applied to both ends of the resistor, and the wiper is moved. The displacement is measured by the voltage between one terminal of the resistor and the wiper. Looking at the component structurally, we can see the following: (Fig. 1) Further, the following formulas apply to the voltage output



Nidec Potentiometer

Model of potentiometer

Wirewound Type

Precision wire winding technology has been used to achieve low noise and long life. Wirewound types include the single turn J series for use in servo drives and the multiturn M series for use in setting.

Conductive Plastic Type

Special film resistors and original contact construction provide long life, with degradation that is theoretically infinitely small. Conductive plastic types include single turn types and linear types, both for use in servo drives.

Cerment Type

The use of cermet resistors allows low price. The degradation is theoretically infinitely small. Cermet tyeps are single turn for use in servo drives and for setting.

Optical Contactless Type

Contactless configuration offers much longer life and lower noise compared with the conventional contact method.



Nidec Copal

Nidec Copal

NIDEC COPAL ELECTRONICS was established in April 1967 in Japan as a specialty manufacturer of electronics components. The company’s philosophy remains unchanged – to be a supplier of high quality products while offering competitive prices. NIDEC COPAL ELECTRONICS began by developing a wirewound trimmer. This product was enthusiastically received by many sectors in the industry. The initial success of the trimmers laid the groundwork for future development of a wide selection of manufactured products that combined electronics at the start of the electronics revolution.

Later, robust sales of cermet trimmers led to the company’s remarkable expansion. Further development efforts led to the release of a succession of new product lines. These included a wide range of motors, encoders, switches and pressure sensors.


  • High linearity through precision wire winding
  • Long life
  • High following characteristics
  • Low noise
  • RoHS compliant


Item J40S J45S J50S
Resistance torelance ± 5%
Effective electrical angle 350° ± 1.5° 353° ± 1.5° 355° ± 1.5°
Mechanical angle 360° continuous
Power rating (at 40 °C) 1W 1.3W 1.5W
Dielectric strength 1000    1 min  Vrms
Insulation resistance 1000 (at DC500 V) MΩ minimum
Rotational torque 0.59 {6}mN·m {gf·cm} maximum 0.69 {7}mN·m {gf·cm} maximum
Peak noise 10 (4 min-1) Ω maximum
Temp. coefficient of resistance ± 50 ppm/°C
Operating temp. range − 55 ~ 85 °C
Maximum rotational speed 100 min-1 200 min-1
Net weight Approx. 58g Approx. 60g Approx. 73g
Connecting accuracy ± 1° (Based on No. 1 terminal)
Protection grade IP40

Resistance Values, Resolution, Independent Linearity, Rotational Life

Nominal resistance
Resolution(%) Independent linearity(%) Rotational life (million cycles)
J40S J45S J50S J40S J45S J50S J40S J45S J50S
500 0.13 0.12 0.1 ±0.15 ±0.1 ±0.1 5 10 10
1 k 0.1 0.1 0.08
2 k 0.08 0.07 0.06
5 k 0.07 0.08 0.07
10 k 0.07 0.05 ±0.15 ±0.15 1 1
20 k 0.05 1
50 k 0.04 0.03


Part Number Designation

J 50 S 500
Series name




Nominal resistance value(Ω)

500, 1 k, 2 k, 5 k, 10 k, 20 k, 50 k

List of Part Numbers

Part number Size Nominal resistance value
J40S 500 φ 40 mm 500 Ω
J40S 1 k 1 kΩ
J40S 2 k 2 kΩ
J40S 5 k 5 kΩ
J40S 10 k 10 kΩ
J45S 500 φ 44.45 mm 500 Ω
J45S 1 k 1 kΩ
J45S 2 k 2 kΩ
J45S 5 k 5 kΩ
J45S 10 k 10 kΩ
J45S 20 k 20 kΩ
J45S 50 k 50 kΩ
J50S 500 φ 50.8 mm 500 Ω
J50S 1 k 1 kΩ
J50S 2 k 2 kΩ
J50S 5 k 5 kΩ
J50S 10 k 10 kΩ
J50S 20 k 20 kΩ
J50S 50 k 50 kΩ

Additional Information

Rated Power Derating Curve