MKS Baratron 727A Series Capacitance Manometers — 727A31TGA2FB EX125D INGEN2PU0 RTNGEN2PU0

Technical Dossier

Product Details And Specifications

MKS Baratron 727A Series: Comprehensive Module Range and Technical Overview

The MKS Baratron 727A series is a family of temperature-controlled capacitance manometers engineered for absolute pressure measurement in high-purity and corrosive-gas process environments. These instruments are deployed across semiconductor fabrication, chemical vapor deposition (CVD), atomic layer deposition (ALD), flat panel display manufacturing, solar cell production, and pharmaceutical process control. The 727A series occupies a critical position in process tool architectures globally, with installed bases in facilities operated by TSMC, Samsung, Intel, ASML, and major petrochemical operators. Its heated sensor design (typically 45°C or 100°C) eliminates condensation-induced measurement drift, making it the reference standard for low-pressure process gas metrology in cleanroom and hazardous-area installations.

The Evolution of Baratron 727A Architecture

MKS Instruments introduced the Baratron capacitance manometer platform in the 1960s as a primary pressure standard independent of gas species. The 627 and 722 series established the foundational dual-diaphragm capacitive sensing principle. The 727A series represents the third-generation heated variant, incorporating a Inconel or Hastelloy C-22 wetted diaphragm for compatibility with halogen-bearing process gases (Cl₂, HBr, NF₃, WF₆). Key architectural milestones include the transition from analog 0–10 VDC output to the current multi-range analog output with RS-232/RS-485 digital interface options, and the introduction of ATEX/IECEx-rated enclosures for Zone 1 and Zone 2 hazardous area classification. The EX125D option code in the SKU 727A31TGA2FB EX125D INGEN2PU0 RTNGEN2PU0 denotes ATEX/IECEx Ex d IIC T4 flameproof enclosure certification, confirming suitability for explosive atmosphere installations. The INGEN2PU0 and RTNGEN2PU0 option codes define the inlet and return gas port configurations respectively. Compatibility with MKS Type 247, 651, and PR4000B readout/control systems has been maintained across all 727A sub-variants, preserving backward integration with legacy process tool wiring harnesses.

Baratron 727A Full Catalog & Functionalities (SKU List)

The following SKUs represent verified models within the MKS Baratron 727A series. Each entry reflects a distinct configuration of full-scale range, heated sensor temperature, wetted material, output signal, and option codes.

727A11TRA1FA: 1 Torr FS, 45°C sensor, Inconel diaphragm, 0–10 VDC analog output, standard process fitting.
727A12TRA1FA: 2 Torr FS, 45°C sensor, Inconel diaphragm, 0–10 VDC analog output, standard process fitting.
727A13TRA1FA: 10 Torr FS, 45°C sensor, Inconel diaphragm, 0–10 VDC analog output, standard process fitting.
727A14TRA1FA: 100 Torr FS, 45°C sensor, Inconel diaphragm, 0–10 VDC analog output, standard process fitting.
727A15TRA1FA: 1000 Torr FS, 45°C sensor, Inconel diaphragm, 0–10 VDC analog output, standard process fitting.
727A21TGA1FA: 1 Torr FS, 100°C sensor, Hastelloy C-22 diaphragm, 0–10 VDC analog output, standard fitting.
727A22TGA1FA: 2 Torr FS, 100°C sensor, Hastelloy C-22 diaphragm, 0–10 VDC analog output, standard fitting.
727A23TGA1FA: 10 Torr FS, 100°C sensor, Hastelloy C-22 diaphragm, 0–10 VDC analog output, standard fitting.
727A24TGA1FA: 100 Torr FS, 100°C sensor, Hastelloy C-22 diaphragm, 0–10 VDC analog output, standard fitting.
727A25TGA1FA: 1000 Torr FS, 100°C sensor, Hastelloy C-22 diaphragm, 0–10 VDC analog output, standard fitting.
727A31TGA2FA: 10 Torr FS, 100°C sensor, Hastelloy C-22, dual analog output (0–10 VDC + 4–20 mA), standard fitting.
727A31TGA2FB EX125D INGEN2PU0 RTNGEN2PU0: 10 Torr FS, 100°C sensor, Hastelloy C-22, dual analog output, ATEX/IECEx Ex d IIC T4 flameproof enclosure, configured inlet/return port options — the specific unit indexed on this page.
727A32TGA2FA: 100 Torr FS, 100°C sensor, Hastelloy C-22, dual analog output (0–10 VDC + 4–20 mA), standard fitting.
727A33TGA2FA: 1000 Torr FS, 100°C sensor, Hastelloy C-22, dual analog output (0–10 VDC + 4–20 mA), standard fitting.
727A41TGA1FA: 1 Torr FS, 100°C sensor, Hastelloy C-22, RS-232 digital output, standard fitting.
727A42TGA1FA: 10 Torr FS, 100°C sensor, Hastelloy C-22, RS-232 digital output, standard fitting.
727A51TGA1FA: 10 Torr FS, 100°C sensor, Hastelloy C-22, DeviceNet interface, standard fitting.
727A61TGA1FA: 10 Torr FS, 100°C sensor, Hastelloy C-22, PROFIBUS DP interface, standard fitting.

Sourcing Hard-to-Find & Obsolete Baratron 727A Parts

The MKS Baratron 727A series has entered the mature-to-declining phase of its product lifecycle. MKS Instruments has progressively transitioned new tool designs toward the 627D, 628D, and 722B series platforms. However, the 727A remains the installed standard in a large population of legacy process tools that cannot be economically retrofitted. DriveKNMS maintains a dedicated inventory program for 727A series units, including ATEX-rated variants such as the 727A31TGA2FB EX125D INGEN2PU0 RTNGEN2PU0, which are particularly difficult to source through standard distribution channels due to their hazardous-area certification requirements. DriveKNMS sources 727A units from decommissioned process tools, certified refurbishers, and authorized surplus channels. All units are catalogued by full option code string to ensure exact configuration matching. Long-term maintenance contracts and consignment stocking agreements are available for facilities with recurring 727A demand.

Quality Control for the Baratron 727A Range

Capacitance manometer validation requires pressure-decade-specific test protocols distinct from those applied to Bourdon tube or piezoelectric sensors. DriveKNMS applies the following procedures to all 727A series units prior to dispatch. Zero-point calibration is performed at each decade of the instrument's full-scale range using a primary reference standard traceable to NIST. Sensor heating element continuity and thermal stabilization time are verified against MKS factory specifications (typically 30-minute warm-up to rated sensor temperature). For ATEX-rated units including the EX125D enclosure variant, flameproof enclosure integrity is inspected per IEC 60079-1, including thread engagement depth, gap dimensions, and cable gland sealing. Output signal linearity is tested across 10%, 50%, and 100% of full-scale range. Units exhibiting zero drift exceeding ±0.15% of full scale or span error exceeding ±0.5% are rejected. All test records are retained and available upon request with each shipment.