When using compressed air applications, not only must high productivity, efficiency and process reliability be ensured across all sectors, but the protection of employees must always be remembered. To do this, engineers use safety valves, which ensure that the system is vented safely. With the VP546 / 746 series, the automation specialist SMC now offers a modular 3/2-way solenoid valve that not only creates a high level of safety. In addition, the solution convinces with a compact design, a modular construction for combination with the maintenance units in the AC-D series from SMC, an integrated non-return valve for the pilot air and is available as an option as a single (single-channel) or redundant (two-channel) system. In addition, the valve can optionally be equipped with a soft start function and an external muffler. This provides engineers with a comprehensive solution for safely designing their pneumatic applications – without compromising on efficiency and productivity.
Release the pressure safely
Although safety features can also be implemented with standard components, the effort and risk of not complying with the harmonized standards is disproportionate to the benefit. Therefore, machine designers benefit from components specially designed for them. This also applies to SMC’s VP546 / 746 series safety vent valve. On the one hand, it enables the sub-safety function “Safe de-energization” (SDE) and on the other hand “Prevention of Unexpected Start-up” (PUS). Overall, it meets all four requirements of Article 2c of the Machinery Directive 2006/42 / EC.
The integrated non-return valve compensates for pressure drops in the pilot air caused by pressure fluctuations on the inlet side. The operating pressure range for the internal pilot air is between 0.25 and 0.7 MPa – with the external pilot air it is between 0.05 and 0.7 MPa. Thanks to the diagnostics of the position of the valve coil by means of safety limit switches, deviations between the input signal and the position of the valve coil are detected. This not only creates more security, but also saves costs and reduces effort.
A large number of safety limit switches from the manufacturers OMRON and Rockwell Automation are available, enabling a versatile and flexible design. The safety valve in the VP546 / 746 series in two sizes is also available in two different variants: on the one hand as a single-channel valve for category 2 and a maximum achievable performance level d and on the other hand as a two-channel valve. duct valve for the highest category 4 and a maximum achievable performance Level e (according to EN ISO 13849). The high B10d-Value of a maximum of 10 million cycles ensures a long service life – and thus has a positive effect on costs.
Easy installation and extra security
The VP546 / 746 series has a modular design both as a simple and as a redundant system and can easily be combined with the maintenance unit AC-D (filter, regulator, lubricator) from SMC. Assembly and disassembly is quick, which also reduces maintenance efforts. The modular connection to a combined maintenance unit (FRL) does not require additional hoses. In addition, the existing block design also reduces space requirements, ensures a uniform and beautiful design and is dustproof and protected from moisture (protection class IP65).
If users select an extra soft start function, the operating pressure range of the external pilot air is between 0.25 and 0.7 MPa. The function creates additional safety by ensuring a gentle pressure build-up and thereby protecting downstream machine components against a sudden build-up of pressure. On the one hand, it prevents accidents caused by fast and uncontrolled movements, and on the other hand, it reduces wear on downstream components. Another option is to mount an exhaust port with an external muffler, which achieves a low sound pressure level and low-noise exhaust noise. The employees’ occupational safety is thus also increased without additional hearing protection.