PMT-4M

PMT-4M: identification and purpose

PMT-4M is classified as a Thermocouple Vacuum Gauge and converts gas pressure into an electrical signal from the heat loss of a heated filament. Select it by the complete designation, series, execution, marking and approved documentation. Similar lettering, housing or connector geometry does not establish identical operating data.

This historical category contains several types of transducing devices. PT, PO and PTS products relate to electrical-power conversion, while PMI, PMT and PMM designations identify vacuum-gauge transducers. Each page therefore follows the actual product function rather than the broad category name. A suffix, series number or extra letter can indicate a materially different circuit, pressure range, rating or interface.

Function and operating circuit

The item converts gas pressure into an electrical signal from the heat loss of a heated filament. Exact input and output conditions depend on the execution. For a power converter, verify voltage, current type, frequency, phase arrangement, rated output, connectors and cooling. For a vacuum transducer, verify the measurement principle, pressure range, operating mode, vacuum connection and compatible measuring instrument.

Numerical values retained from the original catalogue record appear in Technical Details and must be compared with the passport for the actual unit. An aircraft platform or installation system is not assigned by analogy when a reliable source is unavailable.

Selection and compatibility checks

Before replacement, compare the primary and alternative designations, series, input and output ratings, dimensions, mass, connectors, mounting, cooling and documented environmental limits. For a vacuum sensor, additionally compare the conversion constant, emission current or heater resistance where the passport specifies those values.

Related members of one family may use different voltage, frequency, power, pressure range, mounting interface or purpose. The related links below support catalogue navigation and do not establish interchangeability. General technical background is available under Thermocouple Vacuum Gauge.

Incoming inspection and installation

Check the marking and supporting records, housing, connectors, terminals, vacuum fitting, mounting points, seals and any evidence of overheating, impact or corrosion as applicable. Bench testing must follow the documentation for the exact execution; an improvised test voltage or vacuum regime can damage the product.

Install the unit only in the intended circuit with the documented polarity, supply mode, load, cooling and safety provisions. After installation, complete the prescribed functional check. External integrity alone does not demonstrate serviceability or calibration.

Related catalogue positions

Functionally related catalogue products include PMT-2, PMT6-3, PMT6-3M1, PE-11M. They are selected by actual type and family for navigation and do not imply compatibility. More positions are available in the Power Transducers category.

Enquiry information

An enquiry for PMT-4M should state the exact designation, quantity, required condition, marking photograph, delivery scope and required documents. When available, include the designation of the equipment and item being replaced. Price, actual availability, lead time and condition of a specific unit are confirmed separately.