Product Description
The FOXBORO 13A-HS2 is a pneumatic differential pressure (d/p Cell) transmitter from the renowned Foxboro 13A series. Foxboro (now part of Schneider Electric) d/p Cell transmitters have been a long-standing standard in the process industry, known for their exceptional dependability. This specific model measures differential pressure and then transmits a standard pneumatic output signal, typically 3-15 psi (pounds per square inch), to receiving instruments that can be located hundreds of meters away.
The “HS2” in the model code indicates specific characteristics of the transmitter’s capsule and range. The “H” usually refers to a high-range capsule, while “S2” or similar suffixes denote the specific span limits and materials of construction. It is designed for demanding applications requiring robust and reliable differential pressure measurement in various process conditions. The FOXBORO 13A-HS2 is commonly used in flow, liquid level, density, and low-pressure measurement applications. It offers wide span adjustability and broad zero suppression and zero elevation capabilities within its range limits, providing versatility for diverse industrial processes. The transmitter features a durable construction, often with wetted parts made from materials like 316 stainless steel, to withstand corrosive process fluids.
Product Parameters
The FOXBORO 13A-HS2 possesses the following key technical specifications:
| Parameter | Specification |
|---|---|
| Transmitter Type | Pneumatic Differential Pressure Transmitter (d/p Cell) |
| Series | 13A Series (High Range Capsule) |
| Measured Variable | Differential Pressure ($\Delta$P) |
| Output Signal | 3 to 15 psi (or 20 to 100 kPa, 0.2 to 1.0 bar, as specified) |
| Supply Pressure | Typically 20-30 psi (check specific tag for exact required supply) |
| Range (HS2) | Typically 0-850 inH2O (inches of water column) for the ‘H’ capsule. Specific ‘S2’ configuration will define exact span limits within this range. (Example: Span limits 200-850 inH2O) |
| Static Pressure Limit | Up to 14 MPa (2000 psi) (for Model 13A, ‘H’ capsule) |
| Accuracy | $\pm$0.5% of span (for spans between 20-525 inH2O) or $\pm$0.75% of span (for spans between 525-850 inH2O) |
| Repeatability | 0.1% of span |
| Dead Band | 0.05% of span |
| Air Consumption | 0.42 m$^3$/h (0.25 cfm) at standard conditions |
| Wetted Parts Material | Common options include 316 Stainless Steel (SS), Hastelloy C, Monel, Duranickel, Tantalum (depending on specific model code options like SSB/SSB-A). |
| Body Material | SS ASTM A182 GR F316 (typical) |
| Housing Material | Blue, high-impact, glass-filled polycarbonate cover (typical for topworks) |
| Environmental Protection | IP53 (IEC 60529), NEMA 3 (raintight) |
| Operating Temperature | to $+120^\circ$C ( to $+250^\circ$F) (body temperature) |
| Mounting | Direct to process piping or onto a nominal DN 50 (2-inch) pipe (bracket supplied) |
| Process Connections | Typically (2) 1/2 inch FPT (Female Pipe Thread) |
| Air Connections | 1/4 NPT |
| Approximate Mass | 13.6 kg (30 lb) (typical for 13A Series) |
Advantages and Features
The FOXBORO 13A-HS2 offers several advantages and features, solidifying its position as a reliable choice for pneumatic differential pressure measurement:
- Proven Dependability: Foxboro d/p Cell transmitters have a long history of successful and trouble-free installations, demonstrating exceptional reliability in demanding industrial environments.
- Pneumatic Output: Provides a standard 3-15 psi pneumatic signal, which is highly reliable in hazardous areas where electrical signals might pose a risk. It’s also suitable for integration into legacy pneumatic control systems.
- Versatile Application: Ideal for a wide range of measurements including flow (using orifice plates), liquid level (in open or closed tanks), density, and general low-pressure differential applications.
- Wide Span Adjustability: Offers broad zero suppression and zero elevation capabilities, allowing precise adjustment of the measured pressure range within the full limits of the capsule, catering to specific process needs.
- Robust Construction: Built with durable materials for wetted parts (e.g., 316 SS, Hastelloy C), ensuring compatibility with various corrosive process fluids and long service life.
- Ease of Maintenance: Simple design of the topworks and field-replaceable capsule make servicing exceptionally easy and economical. Interchangeability of many topworks parts with other Foxboro pneumatic force balance transmitters helps minimize spare parts inventory.
- High Static Pressure Rating: Capable of handling high static pressures (up to 2000 psi), making it suitable for high-pressure process lines.
- Environmental Durability: The housing provides robust environmental protection (IP53/NEMA 3) against dust and weather.
Application Areas and Application Cases
The FOXBORO 13A-HS2 is widely applied in industries that rely on pneumatic instrumentation for differential pressure measurement, particularly in processes involving liquids, gases, and steam:
- Oil & Gas: Measurement of flow rates in pipelines using orifice plates, liquid level in storage tanks, and differential pressure across filters.
- Chemical Processing: Monitoring flow and level in reactors, distillation columns, and chemical storage tanks, especially in hazardous or explosive atmospheres where pneumatic signals are preferred.
- Refineries: Flow measurement for various hydrocarbon streams, level control in fractionation columns, and pressure monitoring in process units.
- Power Generation: Measuring feedwater flow, steam flow, and condenser levels in conventional and nuclear power plants.
- Pulp & Paper: Controlling flow rates of slurries, levels in digesters and bleaching tanks.
- Water & Wastewater Treatment: Monitoring filter differential pressure, flow in pipes, and liquid levels in treatment tanks.
Application Case: In an older refinery, the existing control system relied heavily on pneumatic instrumentation due to the inherent safety advantages in flammable environments. A critical application involved measuring the flow rate of crude oil through a pipeline using an orifice plate. The FOXBORO 13A-HS2 differential pressure transmitter was chosen for this task. Connected across the orifice plate, the transmitter accurately sensed the pressure drop and converted it into a standard 3-15 psi pneumatic signal, which was then sent to a pneumatic controller in the control room. The ‘H’ capsule’s high range was suitable for the high flow rates and associated differential pressures. Its robust 316 SS wetted parts ensured compatibility with the crude oil. The proven reliability of the 13A series meant stable and accurate flow readings, contributing to efficient process operation and safety without introducing electrical hazards into the hazardous area.
Competitive Comparison
The FOXBORO 13A-HS2 operates in the niche market of pneumatic differential pressure transmitters. While the industry has largely shifted towards electronic (4-20mA or digital HART, Foundation Fieldbus, etc.) transmitters, pneumatic instruments like the 13A series still hold significant ground in legacy plants, hazardous areas, or where air supply is readily available and electrical power is not desired.
Key competitors in pneumatic differential pressure transmitters (primarily in the historical context) would have included:
- Rosemount (now Emerson): While primarily known for electronic transmitters, older Rosemount models (e.g., 1151 series, which also had pneumatic versions) would have competed.
- Honeywell: Their pneumatic instrumentation lines, like the F-series, would have offered competing solutions.
- Taylor (now ABB): Taylor also produced pneumatic transmitters that competed directly with Foxboro in the past.
