EMAS PSA020MS331S EMAS 20 A 3 POLES MTR CNTRL CAM SWIT (0-1) 60

Q: What is the current rating of this cam switch?

The PSA020MS331S has a rated current of 20 A.

Q: What switching function does the PSA020MS331S provide?

The switch provides a 0-1 motor start switching function for three-phase motor control applications.

Q: What is the protection rating of this cam switch?

The PSA020MS331S has an IP54 protection rating, making it suitable for industrial environments.

EMAS PSA020MS331S motor start cam switch, a 20 A three-phase 0-1 rotary switch designed for industrial motor control applications.

SKU: PSA020MS331SMPN: PSA020MS331S

List Price £22.34 ex VAT

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Manufacturer Lead Time

£22.34

Why Choose the EMAS PSA020MS331S Motor Start Cam Switch?

The EMAS PSA020MS331S is a compact and reliable motor start rotary cam switch designed for industrial electrical motor control applications. Part of the EMAS PSA Series cam switch range, it provides dependable manual starting control for three-phase motors in machinery, electrical panels and automation systems.

This motor start cam switch features a three-phase configuration with a 0-1 switching function and a 60° operating angle. Its compact 48 × 48 mm panel mounting design allows straightforward installation while providing reliable switching performance in industrial environments.

With a rated current of 20 A and an AC21A utilisation category, the PSA020MS331S is suitable for motor starting applications requiring dependable manual control, long service life and compact industrial switching capability.

Key Advantages

Compact motor start cam switch designed for industrial applications.
20 A rated current suitable for motor control circuits.
Three-phase motor start configuration for industrial machinery.
0-1 switching function for straightforward motor starting control.
60° switching operation for precise manual operation.
Durable construction designed for reliable long-term performance.

Key Features

EMAS PSA Series motor start cam switch.
20 A rated operational current.
Motor Start switching function.
Three-phase configuration.
0-1 switch position arrangement.
60° operating angle.
48 × 48 mm panel mounting design.
High precision switching mechanism for industrial use.

Reliable Motor Starting for Industrial Systems

Motor start cam switches such as the EMAS PSA020MS331S provide a practical solution for manually controlling the start and stop operation of three-phase motors. The rotary cam mechanism enables clear switching between defined positions while maintaining dependable electrical performance.

The PSA Series is designed for machine builders, panel manufacturers and automation engineers requiring compact motor control devices with reliable switching performance and long operational life.

Typical Applications

Three-phase motor starting systems.
Industrial electrical control panels.
Machine tools and manufacturing equipment.
Pumps and motor-driven equipment.
Automation machinery.
Industrial electrical installations.

Technical Specifications

Tick the specs you need, then view products that match.

Operation	2 positions
Device Type	Cam Switch
Product Series	Emas PSA Series
IP Rating	IP54
Manufacturer	EMAS
Series	PSA Series
Model	PSA020MS331S
Product type	Rotary cam switch
Application	Motor Start
Switch type	Motor Start
Switch position	0-1
Pole / phase configuration	3 Phase
Rated current (Ie)	20 A
Operating angle	60°
Frame size	48 × 48 mm
Utilisation category	AC21A
Insulation voltage (Ui)	690 V
Impulse withstand voltage (Uimp)	4 kV
Protection rating	IP54
Contact material	AgNi
Mechanical life	Minimum 100,000 operations
Electrical life	Minimum 50,000 operations
Operating temperature	-25 to +80 °C
Pollution degree	3
Cable section	1–2.5 mm²
Short circuit breaking capacity (Ics)	6 kA
Mounting type	Panel mounting

Frequently Asked Questions

What is the EMAS PSA020MS331S used for?

The EMAS PSA020MS331S is a motor start rotary cam switch designed for manual starting and control of three-phase motor circuits.

What is the current rating of this cam switch?

The PSA020MS331S has a rated current of 20 A.

What switching function does the PSA020MS331S provide?

The switch provides a 0-1 motor start switching function for three-phase motor control applications.

What is the protection rating of this cam switch?

The PSA020MS331S has an IP54 protection rating, making it suitable for industrial environments.

Where is this cam switch typically installed?

The switch is typically installed in electrical control panels, machinery and industrial motor control systems.

Trusted by Industrial Control Professionals

EMAS PSA Series cam switches are widely used in industrial automation and motor control applications where reliable manual switching, compact design and long service life are essential.

Operation	2 positions
Device Type	Cam Switch
Product Series	Emas PSA Series
Manufacturer	EMAS
Series	PSA Series
Model	PSA020MS331S
Product type	Rotary cam switch
Application	Motor Start
Switch type	Motor Start
Switch position	0-1
Pole / phase configuration	3 Phase
Rated current (Ie)	20 A
Operating angle	60°
Frame size	48 × 48 mm
Utilisation category	AC21A
Insulation voltage (Ui)	690 V
Impulse withstand voltage (Uimp)	4 kV
Protection rating	IP54
Contact material	AgNi
Mechanical life	Minimum 100,000 operations
Electrical life	Minimum 50,000 operations
Operating temperature	-25 to +80 °C
Pollution degree	3
Cable section	1–2.5 mm²
Short circuit breaking capacity (Ics)	6 kA
Mounting type	Panel mounting
IP Rating	IP54

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