Trafag Highlights Three Picostat Mechanical Pressure Switches Tailored to Precision in Dynamic Demands

­Trafag, a leading manufacturer of high-accuracy measurement devices, highlights its Picostat family of mechanical pressure switches with three complementary models, the PST4B 9B4, PST4M 9M4 and PST4K 9K4, engineered to deliver reliable, repeatable switching performance in demanding shipbuilding, engine manufacturing, railway, machine tool and hydraulic applications. At the heart of each Picostat model is a different mechanical sensing principle that caters to specific pressure dynamics and media conditions. 

The PST4B 9B4 uses a bellows measuring principle, offering a mechanically simple and robust sensing element with high durability and stable switching over time, ideally suited to vacuum, low and medium pressure ranges from −0.6…3.4 to 4…40 bar (−8…45 to 60…500 psi). This design, combined with high over‑pressure capability up to 50 bar, repeatability of ±0.5% FS (typical), fixed switching differentials and an adjustable switch‑point range of 10…90% FS on request, provides precise, consistent switching where fine control and wide media temperature capability from −25…+125 °C, down to −40 °C with specific sensor options, are critical.

The PST4M 9M4 is built around a membrane measuring principle that provides reliable pressure sensing for hydraulic and other media within medium to high pressure ranges from 1…10 to 10…100 bar (14…150 to 150…1500 psi). This membrane design is optimized for applications where stable pressure levels and moderate dynamics dominate, combining repeatability of ±2.0% FS (typical) with fixed switching differentials tailored to each range and an adjustable switch‑point window of 10…90% FS on request. With a media and ambient temperature range of 0…+80 °C and a rugged anodized aluminium EN AW‑6082 housing, the PST4M 9M4 offers an effective balance of robustness and accuracy for a wide variety of industrial and mobile hydraulic systems.

For highly dynamic, high‑pressure environments, Trafag offers the PST4K 9K4 with a piston measuring principle using a 1.4035 piston and PTFE sealing. This configuration is designed for high pressures and pulsating hydraulic media, covering a broad span from 1…10 to 40…400 bar (14…150 to 580…5800 psi) with high over‑pressure capability up to 600 bar (8700 psi depending on range), supporting long service life under severe pressure shocks and spikes. The PST4K 9K4 achieves repeatability of ±1.0% FS (typical) with fixed switching differentials matched to each range and an adjustable switch‑point range of 10…90% FS on request, while its wide media temperature range of −25…+125 °C and ambient range of −25…+85 °C enable reliable operation in both hot and cold process conditions.

All three Picostat switches share key installation and connectivity advantages that simplify integration across diverse systems. An output signal via a floating change‑over contact (SPDT) offers easy integration into existing control circuits without additional interface relays. A standardized EN 175301‑803‑A (DIN 43650‑A) plug connection and protection up to 95% relative humidity support safe, reliable operation in industrial power environments, humid engine rooms and coastal installations. Each model combines a compact, rugged, IP65‑protected housing with high vibration resistance up to 5 g, shock resistance of 50 g for 3 ms and installation in any mounting position, ensuring dependable operation in harsh, space‑constrained environments such as engine rooms, manifolds and mobile equipment.

The Picostat portfolio further increases versatility with multiple pressure connections, plus mounting accessories such as a flange with O‑ring, fixing set, covering cap and lead seal to simplify panel mounting and on‑site installation. Depending on the model, users can choose among sensor options including bronze bellows with aluminium or brass housings and stainless steel bellows for the 9B4, FKM membrane sensors with anodized aluminium housings for the 9M4, and piston sensors with PTFE sealing for the 9K4, aligning material selection with media and corrosion requirements.

Across the range, approvals and conformity with ABS, BV, CCS, DNV‑GL, KRS, LR or LRS, NKK where applicable, RINA, RMRS for the 9B4, and EN 60730‑1 / ‑2‑6 Type 2.B.H simplify acceptance in marine and safety‑related applications, reducing certification effort for shipbuilding and OEM projects. By combining targeted sensing mechanisms within a common, vibration‑resistant Picostat platform, Trafag enables engineers to select the optimal mechanical switch for their specific pressure dynamics while maintaining a consistent, proven interface across their installations.

For more information about Trafag and its products, please go here.