EMAS PSA020OK421S measuring cam switch, a 20 A three-phase four-position rotary switch designed for industrial electrical measurement applications.
£26.07
The EMAS PSA020OK421S is a precision three-phase measuring cam switch designed for selecting measurement circuits in industrial electrical panels and control systems. As part of the EMAS PSA series rotary cam switches, it provides reliable manual switching, compact installation and durable operation for measurement and monitoring applications.
This switch is specifically developed for electrical measurement systems where multiple circuit positions are required. Its four-position selector design allows operators to switch between measurement points while maintaining dependable mechanical performance in industrial environments.
With a 20 A rated current, three-phase configuration, four-position operation and 45° switching angle, the EMAS PSA020OK421S is suitable for use in control panels, measurement equipment and industrial power monitoring applications.
Measuring cam switches such as the EMAS PSA020OK421S provide a practical method of manually selecting electrical measurement circuits. Their mechanical selector mechanism enables operators to switch between predefined measurement positions within industrial control and monitoring systems.
The PSA series is designed for applications requiring dependable switching, compact panel installation and long operating life. The PSA020OK421S is suitable for integration into electrical distribution panels, instrumentation systems and industrial automation equipment.
| Manufacturer | EMAS |
|---|---|
| Series | PSA Rotary Cam Switches |
| Model | PSA020OK421S |
| Product type | Measuring cam switch |
| Rated current | 20 A |
| Number of phases | Three-phase |
| Number of positions | 4 positions |
| Switching angle | 45° |
| Frame size | 48 × 48 mm |
| Usage category | AC21A |
| Insulation voltage | 690 V |
| Impulse withstand voltage | 4 kV |
| Protection rating | IP54 |
| Mechanical life | minimum 100,000 operations |
| Electrical life | minimum 50,000 operations |
| Contact material | AgNi |
| Operating temperature | -25 to +80 °C |
The EMAS PSA020OK421S is a measuring cam switch used for selecting electrical measurement circuits in industrial control and monitoring systems.
The PSA020OK421S has a rated current of 20 A.
This measuring cam switch features a four-position selector arrangement.
The PSA020OK421S is designed for three-phase industrial electrical measurement applications.
The switch is typically installed in electrical control panels, distribution cabinets and industrial measurement systems.
EMAS PSA series cam switches are widely used in industrial control and measurement applications where reliable manual switching, compact installation and long service life are required.
● Service Agreements
Credit Accounts
Our service agreements are built to support long term procurement relationships. By working closely with engineering teams and procurement departments, we help streamline purchasing processes while ensuring consistent access to critical components and sourcing support when it matters most.
● frequently asked questions
At Led Controls Ltd we help engineers source the right automation and control gear with confidence. below are quick answers to what we are asked most often.
We supply all leading manfacturers in our industry. we offer next day delivery on most poplour products.
Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.
Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.
Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.
Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.
● latest blog
LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...