The PDV-500 series drain valves are heavy duty zero loss pneumatic drain valves that save energy. With no electricity needed for operation, the PDV-500 Series is well suited for remote or portable applications and is safe to operate in hazardous areas. As a demand-operated drain, the PDV-500T automatically does the work of draining for you, eliminating the guess work of setting the cycle time of the timed drain valve. As condensate levels change, the PDV-500T automatically adjusts to drain as needed, without permitting valuable compressed air to escape. Designed with a full flow ball valve and proprietary pilot valve using a magnet and proximity switch, the PDV-500T will not clog. This unique pilot valve design allows the control air to be totally separated from the condensate, preventing any attraction of pipe scale. The ball valve eliminates the need to install a strainer. This means better dependability than competitive units. The see-through vessel allows visual inspection of the condensate. The test button, which is included on both the brass and stainless steel units, make it easy to check valve operation or manually drain the system. The Van Air Systems PDV-500T is a versatile draining system ideal for receivers, dryers, tanks, drop legs, pipes, and any equipment requiring regular condensate removal.