MST-30A

MST-30A pressure switch for aircraft systems

MST-30A is a compact heat-resistant aircraft pressure switch designed for monitoring gauge pressure in onboard hydraulic, oil, fuel and other fluid systems. The unit closes an electrical circuit when the pressure of the working medium rises to the preset value. It is used in aircraft and helicopter systems where reaching a defined pressure level must be converted into a discrete electrical signal for indication, control or monitoring circuits.

Pressure signalling through MST-30A

The switch operates on pressure increase. When pressure in the connected line reaches the specified setting, the internal contact mechanism closes the circuit. This makes the unit suitable for systems where pressure build-up must be confirmed or where a warning / control signal is required at a defined threshold. The device does not provide continuous pressure indication. It functions as a discrete pressure relay with a fixed switching point.

MST-30A in hydraulic, oil and fuel systems

MST-30A is used in aircraft hydraulic, oil and fuel systems, depending on the installation and compatibility of the working medium. The controlled media may include neutral gases, air, aviation oils, hydraulic fluids and fuel. In helicopter applications, the unit is used on Mi-8 / Mi-17 family aircraft and other aviation platforms, depending on configuration. Exact applicability must be confirmed through the aircraft parts catalog, system diagram or maintenance documentation.

Construction and operating features of MST-30A

The unit is built in a durable metal housing with a pressure connection for installation into a hydraulic, pneumatic or fluid line. The electrical interface is made through a plug connector for integration into the aircraft wiring system. The heat-resistant execution allows operation in areas exposed to elevated temperature, vibration and working media typical of engine, transmission and onboard service systems. The contacts are rated for both resistive and inductive loads within the specified limits.

Identification and ordering of MST-30A

Before ordering MST-30A, the full designation, pressure setting and switching logic should be checked. The “A” index indicates contact closure on pressure rise. Other MST-series units may have different pressure settings, working logic or environmental execution. For correct selection, provide the aircraft type, installation system, required pressure threshold, working medium, electrical circuit parameters and a photo of the existing unit marking. The product is also known under alternative designations MST-30A and МСТ-30А.

Product Type: Compact heat-resistant pressure switch / pressure signalling device
Function: Generation of electrical signal when working pressure drops to a specified value
Application / Where Used: Aircraft, industrial and special-purpose pressure monitoring systems
System / Installation Area: Hydraulic, oil, pneumatic, gas and liquid pressure circuits
Typical Aircraft Application: Mi-8 helicopter hydraulic systems, M-101T aircraft and other compatible equipment, depending on configuration
Controlled Media: Neutral gases, air, liquids, aviation oils including MS-8RK, hydraulic fluids including NGZh, oxygen where applicable
Designation Meaning: MST — compact heat-resistant pressure switch; 30 — nominal switching pressure; S — special fitting / pressure-drop signalling version
Circuit Voltage: 27 V DC
Switched Current, Resistive Load: Up to 1.5 A
Switched Current, Inductive Load: Up to 0.5 A
Operating Temperature Range: −60 to +180 °C
Short-Term Temperature Resistance: Up to +220…+270 °C, depending on conditions and documentation
Maximum Operating Altitude: Up to 30,000 m
Weight: Not more than 250 g
Assigned Operating Time: Up to 30,000 h
Construction: Pressure fitting, sensing element, spring mechanism, electrical contact group
Alternative Designations: MST-30S; МСТ-30С
Technical Documentation: Product passport and technical documentation available upon request

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Returns & Changes (Restocking Fee)
For selected items, a RESTOCKING FEE of 10% may apply in case of return, order cancellation, or changes to the order specifications. This condition applies only to certain products and is confirmed at the order approval stage.

Warranty
All products are covered by a standard 6-month warranty.
Extended warranty is available upon request and is agreed individually; it may affect the final product price.