On-off valves

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On-off valves are basically used to open and close the main air supply to a system.


Functions


Supplying with air


Einschaltventil belueften.png


Supplying with air

Monday morning - the machine/system is switched on, including the supply of air. How does this happen?
Just as in an EMERGENCY OFF situation, switching elements such as valves are in a defined or, in extreme cases, an undefined state. In order to avoid system parts jerkily moving into their start of working positions after system downtime, the pressure of the supply air can be slowly built up when it is switched on.
To do this, another on-off valve with a gradual pressure build-up is positioned downstream of the first. On-off valves with gradual pressure build-up initially increase the pressure slowly up to approx. 50% of the set operating pressure. Once this 50% has been reached, the full pressure is built up all at once.

 


Exhausting

 

Einschaltventil entlueften.png


Exhausting

In order to avoid inadvertent movements or forces in a switched off system, the valve exhausts as it closes. This means that hazardous "residual air" can escape from the system.

Safety

The soft-start/quick exhaust valve MS6-SV substantially reduces this risk in a compressed air system.

MS6-SV.png

The electro-pneumatic soft start/quick exhaust valve MS 6-SV is intended for reducing pressure quickly and safely and for building up pressure gently in pneumatic pipeline systems and terminal equipment in industry.
The device is an intrinsically safe, redundant mechatronic system conforming to the requirements of EN ISO 13849-1. The safety-related pneumatic protection and safe exhausting are ensured, even in the case of valve defects (e.g. sticking of a slide). Thanks to the monitored 2-channel design, the device fulfils controller category 4 requirements. Thus, with correct installation and consideration of the specific application data, performance level "e" can be attained.
The device receives secure enable signals (EN1/EN2) via the electrical connection (multi-pin plug socket NECA Sub-D, 9-pin) from commercially-available electronic or electromechanical safety switching devices,which monitor the machine's protective devices (e.g. emergency off, light grid, electrical door switch on the protective housing, etc.)
Performance level “e” / Category 4 to EN ISO 13849-1
Conforms to EN 61508
A switching time delay adjusted via a flow control valve for gradual pressure build-up

Optional pressure sensor