MST-25A

Pressure signalling through MST-25A

The switch operates on pressure increase. When pressure in the connected line reaches the setpoint, the internal contact system closes the electrical circuit. This makes the unit suitable for applications where the monitored system must confirm pressure build-up or signal that a specified pressure threshold has been reached. The device does not provide continuous pressure indication like a gauge. It works as a discrete pressure relay with a fixed switching point.

MST-25A in hydraulic, fuel and oil systems

MST-25A can be used in aircraft hydraulic systems, fuel systems and oil systems, depending on the installation and compatibility of the working medium. The controlled media may include neutral gases and liquids, aviation oils, hydraulic fluids and gaseous oxygen. In helicopter applications, the unit is associated with systems installed on aircraft such as Mi-171E, depending on configuration. Exact applicability must be confirmed through the aircraft maintenance documentation or parts catalog.

Construction and operating features of MST-25A

The pressure switch is built for operation in high-temperature aircraft environments. The compact housing, pressure connection and internal contact mechanism allow installation in limited spaces where system pressure must be monitored locally. The heat-resistant version is designed for operation in areas exposed to elevated temperatures, vibration and operating loads typical of aircraft systems. The electrical contacts are rated for both resistive and inductive loads within the specified current limits.

Identification and ordering of MST-25A

Before ordering MST-25A, the full designation and switching logic should be checked. The letter “A” indicates operation on pressure increase, with contact closure when the set pressure is reached. Other MST versions may have different switching logic or setpoints. For correct selection, provide the aircraft type, system of installation, required pressure setting, working medium, electrical circuit parameters and a photo of the existing unit marking. The product is also known under alternative designations MST-25A and МСТ-25А.