When selecting a pressure transmitter for critical industrial processes, understanding the technical specifications is paramount. The ABB LM80.A pressure transmitter stands out as a highly reliable and accurate device designed for a wide range of applications. This article provides a detailed technical deep-dive into the LM80.A, exploring its operating principle, key features, and the specifications that make it a top contender in the market.
At its core, the ABB LM80.A is a piezoresistive pressure transmitter. This means it uses a silicon sensor whose electrical resistance changes when mechanical stress (in this case, pressure) is applied. The transmitter's sensing element consists of a thin silicon diaphragm. When process pressure acts on this diaphragm, it deflects slightly, causing a change in the resistance of implanted piezoresistive strain gauges.
This resistance change is minuscule and is converted into a standardized electrical signal by the transmitter's sophisticated electronics. The most common output is a 4-20 mA analog signal, which is proportional to the measured pressure range. This signal is highly immune to electrical noise and can be transmitted over long distances, making it ideal for industrial environments.
The performance of the LM80.A is defined by a set of impressive specifications. Here’s a breakdown of the most critical ones:
One of the most significant advantages of the LM80.A is its high accuracy, typically up to ±0.1% of the calibrated span. This precision ensures reliable process control and quality assurance. Furthermore, it boasts excellent long-term stability, meaning its calibration drifts very little over time, reducing maintenance needs and total cost of ownership.
Built for harsh conditions, the LM80.A features a stainless steel housing that provides excellent protection. The wetted parts (the components that contact the process medium) are also available in various stainless steels (e.g., 316L) to handle corrosive liquids and gases. This makes it suitable for industries like chemical processing, water treatment, and oil & gas.
The transmitter can operate effectively in ambient temperatures from -40°C to 85°C (-40°F to 185°F). This wide range ensures reliable performance in extreme climates, from freezing cold outdoors to hot industrial plants.
The ABB LM80.A is available for a vast selection of pressure ranges, from low vacuum to very high pressures (e.g., up to 600 bar). It can measure gauge pressure (relative to atmospheric pressure), absolute pressure (relative to a perfect vacuum), and differential pressure.
While the standard output is a 4-20 mA HART® signal, many variants of the LM80.A support HART communication. The HART protocol allows for remote configuration, calibration, and diagnostics using a hand-held communicator or asset management software, enabling predictive maintenance strategies.
