Foxboro 13A-MS2 13A Series Differential Pressure Transmitters

Foxboro 13A-MS2 13A Series Pneumatic Differential Pressure Transmitter

Configured for precise fluid head and differential pressure sensing in process networks, the Foxboro 13A-MS2 (13A-MS2 Pneumatic Differential Pressure Transmitter) provides direct physical/electrical execution. The transmitter utilizes a force-balance d/p Cell mechanism to convert differential pressure inputs into proportional pneumatic output signals ranging from 3-15 psi (20-100 kPa). This mechanical conversion maintains stable loop feedback across orifice plates, venturi tubes, and liquid level tank monitoring points without relying on internal microprocessor electronics.

Hardware Specifications

4-20 mA HART Loop Protocol and Channel Isolation Integrations

The mechanical force-balance d/p Cell construction isolates the process medium from downstream signal paths using 316L stainless steel diaphragms. In electronic configuration variants, the 4-20 mA HART loop protocol current loop drives signal transmission across long field runs while suppressing electromagnetic interference (EMI). The isolated physical diaphragm coupling prevents process line voltage surges and common-mode noise from propagating onto control system input cards. Furthermore, when integrating pneumatic outputs with hybrid DCS environments, P/I conversion interfaces maintain strict channel-to-channel isolation to eliminate ground loop currents across control nodes.

Frequently Asked Questions

Q: How is zero and span adjustment performed on the 13A-MS2 in the field?

A: Field calibration relies on accessible physical vernier adjustment controls located directly on the transmitter body, allowing on-line zero and span calibration up to a 10:1 turndown ratio without specialized software tools.

Q: What air supply specification is required for the pneumatic signal output?

A: The pneumatic output model converts differential pressure into a standard 3-15 psi (20-100 kPa) signal, requiring clean, dry instrument-grade supply air regulated within nominal system limits.

Q: What wetted materials protect the transmitter capsule from corrosive process fluids?

A: The sensing capsule, diaphragm elements, and internal process gaskets utilize 316L stainless steel construction to prevent chemical degradation and pinhole corrosion in aggressive fluid lines.

Field Installation Guidelines

Mount the transmitter vertically using a rigid 2-inch pipe stand or flat surface mounting bracket to minimize mechanical vibration effects on the force-balance mechanism. For liquid flow applications, mount the unit below the primary flow element tapings; for gas applications, mount it above the tapings to allow condensate to drain naturally back into the process line.

Connect impulse piping to the 1/4-inch or 1/2-inch NPT female process connections. Apply PTFE tape or pipe thread sealant exclusively to male NPT fittings, keeping the leading two threads bare to prevent thread compound from fouling internal diaphragm cavities. Ensure all pneumatic supply lines utilize clean, dry, oil-free instrument air filtered to prevent nozzle-flapper orifice blockages. Ground the transmitter metal chassis to the local plant earth grid to discharge static build-up.