Scale Dials

Part Number	Description / PDF	Quantity
P0400-27 Wickmann / Littelfuse	FACE PLATE 0-10 DIAL REV A	0
P0400-12 Wickmann / Littelfuse	FACE PLATE 0.05-1 SEC REV. B	29
P0400-83 Wickmann / Littelfuse	FACE PLATE 1-60 SEC. REV. H	58
P0400-86 Wickmann / Littelfuse	FACE PLATE 0.1 TO 10 MIN.REV.G	164
P0400-82 Wickmann / Littelfuse	FACE PLATE 0.1-10 SEC. REV. H	1
P0400-17 Wickmann / Littelfuse	FACE PLATE 1-30 SEC. REV. E	0

Scale Dials

Potentiometers and variable resistors are three-terminal resistors with a sliding contact that forms an adjustable voltage divider. Scale dials are precision components enabling manual adjustment of electrical resistance, critical for controlling signal levels, calibration, and system optimization in electronics.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Rotary Potentiometers	360 rotational adjustment with logarithmic or linear taper	Audio volume controls, industrial machinery
Slide Potentiometers	Linear sliding contact for precise position control	Graphic equalizers, medical equipment
Digital Potentiometers	IC-based resistance adjustment via digital signals	Automotive systems, IoT devices
Precision Trimmer Potentiometers	Miniature size with screwdriver adjustment	Circuit calibration, aerospace sensors

3. Structure and Components

Typical construction includes:

Resistive element (carbon film, wirewound, or conductive plastic)
Movable wiper contact assembly
Mechanical shaft with scale dial (10-300 rotation range)
Calibration markings (linear/logarithmic scales)
Enclosure (metal/plastic housing for environmental protection)

4. Key Technical Specifications

Parameter	Description	Importance
Resistance Range	10 to 10M	Determines adjustment resolution
Taper Type	Linear/Audio/Custom	Defines resistance vs. rotation relationship
Resolution	0.1-5% precision	Critical for measurement accuracy
Power Rating	0.1-5W	Prevents thermal overload
Mechanical Life	10,000-100,000 cycles	Long-term reliability indicator

5. Application Fields

Key industries include:

Consumer electronics (audio/video equipment)
Industrial automation (PLC systems)
Medical devices (diagnostic equipment)
Automotive (HVAC controls, sensors)
Aerospace (flight control systems)

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Features
Bourns Inc.	PTR0X000XGLC	10-turn precision trimmer
Vishay Precision Group	3006P Series	High-stability foil technology
ALPS Alpine	RK09K Series	Sealed rotary design
TT Electronics	Precision Trimmer	Medical-grade reliability

7. Selection Guidelines

Key considerations:

Electrical requirements (resistance range and tolerance)
Mechanical specifications (shaft size/duty cycle)
Environmental factors (temperature/humidity resistance)
Cost vs. precision trade-offs
Case Study: Audio mixer using Bourns PTR08 requires 1% resolution

8. Industry Trends

Current developments include:

Miniaturization (SMD-compatible designs)
Integration with digital interfaces (IoT compatibility)
Advanced materials (graphene-enhanced resistors)
Increased reliability for harsh environments
Smart sensor applications growth (2023-2028 CAGR: 6.2%)