MST-2.5S
Pressure switch
Description
MST-2.5S in aircraft pressure monitoring systems
The MST-2.5S is a compact heat-resistant aircraft pressure switch designed to generate an electrical signal when a preset excess pressure level is reached. It is used in hydraulic, pneumatic and other onboard systems where pressure must be monitored by a simple discrete signal. The unit does not measure pressure continuously like an analog sensor. Its task is to switch an electrical circuit when the pressure reaches the specified setting.
Full descriptionCollapse description
Pressure signaling function of MST-2.5S
The MST-2.5S works as a pressure-controlled electrical switch. When the pressure of the working medium rises to the set actuation value, the internal mechanism changes the state of the electrical contacts. This signal can be used by cockpit indication, warning circuits, protection logic or automatic control equipment. In aircraft systems, such switches are useful because they give a clear “pressure reached / pressure not reached” signal without requiring complex signal processing.
MST-2.5S in hydraulic and pneumatic circuits
The pressure switch is used in aircraft hydraulic and pneumatic systems, including helicopter applications. It may be installed in pressure monitoring circuits, protection circuits or signaling lines where the system must confirm that pressure has reached the required level. The MST-2.5S is associated with Mi-26 helicopter equipment, depending on the system configuration. Exact installation point and circuit function should always be checked by the aircraft maintenance documentation.
Working media for MST-2.5S
The MST-2.5S can operate with neutral liquids and gases, including NGZh hydraulic fluid, MS-8RK oil and gaseous oxygen according to supplied reference data. This makes the switch suitable for several types of aircraft systems, but compatibility still has to be confirmed for the exact installation. The condition of seals, pressure port cleanliness and compatibility with the working medium are important. A pressure switch that was previously used in one medium should not be installed in another system without proper inspection and approval.
Heat-resistant design of MST-2.5S
The unit is designed for operation over a wide temperature range and can be used in demanding aircraft environments. Heat resistance is important for systems located near engines, hydraulic equipment or other areas where temperature may rise during operation. The switch is also designed to withstand vibration loads typical of aviation service. Before installation, the housing, connector, pressure fitting and contact condition should be checked, especially if the unit was stored for a long time.
MST-2.5S and MSTV-2.5S designations
The product may be found under designations MST-2.5S, MSTV-2.5S, MST-2,5S and MSTV-2,5S depending on documentation, transliteration style or supplier records. For procurement, the original marking on the unit and the aircraft documentation should be checked carefully. Similar pressure switches may differ by actuation pressure, thermal execution, connector, thread, contact arrangement or working medium approval. The pressure setting must not be assumed from the general series name only.
Supply and inspection of MST-2.5S
For procurement or replacement, the full designation MST-2.5S / MST-2,5S should be specified together with the required pressure setting. Before installation, the switch should be checked for marking, housing condition, thread and pressure port condition, contact switching at the set pressure, insulation, connector condition and compatibility with the aircraft system. For aviation use, product passport or official technical documentation should be confirmed wherever available.
Technical details
- Product Type
- Aircraft pressure switch
- Designation
- MST-2.5S
- Alternative Designations
- MST-2,5S; MSTV-2.5S; MSTV-2,5S
- Function
- Electrical circuit switching at preset pressure
- Application / Where Used
- Aircraft hydraulic and pneumatic systems
All specificationsCollapse specifications
- System / Installation Area
- Pressure monitoring, signaling and protection circuits
- Compatible Aircraft / Equipment
- Mi-26 helicopters and other aircraft systems depending on configuration
- Measured / Controlled Parameter
- Excess pressure of working medium
- Set Actuation Pressure
- 2.5 kgf/cm²
- Operating Voltage
- 27 V
- Switching Current, Resistive Load
- Up to 1.5 A
- Switching Current, Inductive Load
- Up to 0.5 A
- Working Medium
- Neutral liquids and gases, NGZh fluid, MS-8RK oil, gaseous oxygen
- Operating Temperature Range
- −60 to +180 °C
- Vibration Resistance
- Amplitude up to 1 mm in the 10–5000 Hz range
- Weight
- Not more than 0.25 kg
- Inspection / Testing
- Pressure actuation check, contact switching check, connector inspection, pressure port inspection, housing inspection and compatibility verification
- Technical Documentation
- Product passport / official technical documentation
Payment & delivery
Orders ship from our hub in Dubai. Partner stock is first transferred to Dubai, then shipped to you.
Dubai stock: 100% before dispatch. Partner stock (Remote stock) and Pre-order: 50% advance payment to start the order and 50% before shipment from Dubai to you.
Availability, lead time, delivery cost and payment terms are confirmed for your order before payment.
Payment & delivery terms




