A pressure transmitter does control? Yup
Key Highlights
- Integrates local control with onboard relays, enabling immediate start/stop of equipment without external controllers.
- Offers fast measurement response times of 80 ms, with an optional 40 ms for surge applications, enhancing process responsiveness.
Onboard microprocessors and Ethernet ports let everyone boast their devices can do control, but few can back up those claims. One that can is Emerson’s Rosemount 4051S pressure transmitter, which performs local, real-time control, eliminating the need for a PLC or other controller.
Two onboard, 250 V, 5 A, relay switches give Rosemount 4051S control capability, and each can be configured to start or stop pumps, motors and other equipment. These switches can also deliver alerts based on pressure, flow, totalized flow, level, volume or module temperature.
“Adding two independent, high-power, high-current relay switches directly into the transmitter lets users respond to its accurate and reliable measurements more quickly and easily by immediately turning valves, pumps or other devices on or off without needing the usual interposing relays,” says Connor Oberle, product manager for Rosemount pressure products at Emerson. “This means Rosemont 4051S can function as a controller with two outputs for basic applications. They’re also certified for safety instrumented systems (SIS), so they can serve as an extra level of redundancy.”
Rosemount 4051S also delivers 80-millisecond and optional 40-millisecond response times for processing measurements, which let it run smoothly in the toughest processes and harshest settings. “Getting down to 40 milliseconds also unlocks surge applications and events, which typically need 50-millisecond response times,” adds Oberle. “Regular pressure transmitters aren’t fast enough. Rosemount 4051S’s fast-response times also enable smart diagnostics that couldn’t be done otherwise.”
Because speed and accuracy require capability to be effective, Rosemount 4051S also delivers an 800-to-1 turndown ratio, allowing a 1,000-inch range sensor to be ranged down to just 1.25 inches, which is four times better than its predecessor. “Its far wider rangeability means this new pressure transmitter can cover one, two or three different types of sensors with one product,” says Oberle. “This also lets users greatly reduce their devices inventories, and specify Rosemount 4051S in projects more confidently, knowing they won’t have to make as many changes later.”
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To track its innovative operations and further streamline responses, Rosemount 4051S provides diagnostics that can be accessed from up to 50 feet via Bluetooth. “These diagnostics are also easier to configure and set up with Rosemount 4051S’s software, larger, backlit user interface, and AMS Device Configurator mobile app,” explains Oberle. “For example, configuring devices to detect plugged-lines used to require many selections and was complicated. Now, configuration is simplified, and only requires a couple of clicks.”
Likewise, Rosemount 4051S offers guided proof testing with walkthroughs and logging, which include partial proof verification of output electronics without applying pressure, and comprehensive proof testing with full-pressure tests of the sensor's diaphragms. It also comes with an in-situ, proof-test option that verifies output electronics and electronics in the sensor module are working correctly. Rosemount 4051S is also certified as SIL 2/3 and IEC 61508 compliant.
“Pressure switches in general don’t usually have diagnostics, so it’s hard to know if instructions were carried out, or if they’ll work the next time,” adds Oberle. “Rosemount 4051S’s diagnostics show its proper state, whether closed or open actions occurred, and monitors applied power to make sure they can be done again in the future.”
For more information, visit www.emerson.com/Rosemount4051S
