Introduction • On Precision Pots • General Product Definitions • Construction Details • Multiturn Precision Pots • Resistive Elements • Terminals • Shaft-Rotor Assembly • Mechanical Rotation • Mounting Methods • 3540 Family • 3590 Family • Knobpot 3600 Family • Single-Turn Precision Pots • 6537/6637 Family • 6539/6639 Family • 3680 Pushbutton Family • Special Precision Pots • Shafts • Mounting Styles • Bearings • Torque • Linearity • Wiper Load • Low Current Applications • High Rotational Speed • Angles • Additional Taps • Sealed Units • Multicup Assemblies • Envelopes • Environmental • Competition • Useful Terms

Sealed Units

Bourns precision potentiometers can be sealed to military specifications for Underwater Dip Test at 70 °C. Combinations of shaft, body or panel seal are available. A variety of custom seal approaches are available, including oil-filled units.

Shaft seal, which is normally achieved by the use of o-rings, will increase the torque of the specific product. The increased torque will not necessarily reduce the rotational life of the potentiometer. However, the seal integrity degrades with repeated adjustment of the shaft and may not meet the life expectancy of the product.