Focus on pressure

Pressure transmitter

 

The model 386 pressure transmitter has a flush-tip, zero-cavity design. This configuration eliminates the traditional measurement challenges of pressure transmitter port clogging. It also removes installation torque effects on the output signal. The model 386 incorporates a solid stainless-steel machined diaphragm (Inconel optional), along with all-welded sealed housings. The model also has an isolated sensor, which eliminates the need for adjustments to the pressure transmitter after installation.

Units are available in 13 uniquely configurable standard ranges, covering 0–150 to 0–10 K psig or psis, along with a variety of electrical connections. Depending upon range, the model can withstand up to 1.5 times proof pressure (10 K psi range) and up to 5 times burst pressure (or 30 K psi, whichever is less). Typical applications for the model 386 flush-tip pressure transmitter include paint finishing systems, automotive and aerospace test stands, in-laboratory research and development, process pressure measurements, adhesives, sludge and slurries, and viscous media measurements. 

Viatran, www.viatran.com  

Series pressure transmitters

 

The TPL series pressure transmitters have 0.5–4.5 V ratiometric output and a ±0.25 percent nonlinearity, hysteresis, and repeatability specification (best fit straight line) over an operating temperature range of –40° to +125°C. The series is digitally compensated to provide accurate, reliable pressure measurements with long-term stability. The transmitters are suited for original equipment manufacturer requirements within the industrial automation, hydraulics and pneumatics, agricultural and off-road vehicle, HVAC, water treatment, and general instrumentation sectors.

Gauge pressure is detected using a four-arm, active strain-gauge bridge incorporating highly stable resistors. The resistors are fused to a high-purity ceramic element. Changes in pressure on that element cause bridge voltage changes, conditioned by onboard processing electronics. The TPL series may be specifically configured for a wide range of pressure ports and electrical connections, to cover all typical installation requirements. Units are available in a choice of 14 unique standard pressure ranges (both BarG and psig), 20 unique 303-grade stainless-steel pressure port styles, and eight unique seal materials, including EPDM for potable water applications.

Additional options include a choice of a IP65-rated mini-DIN plug and socket or a IP6K9K-rated bayonet connector. U.K. Accreditation Service-accredited calibration is also optional.

TT Electronics, www.ttelectronics.com  

Pressure transmitters

 

The ProSense SPTD25 pressure transmitters have an all-stainless steel thin-film sensing element. They can be used to sense any compatible media. The transmitters resist vibration, shock, and electromagnetic or radio frequency interference, and are accurate over a broad-compensated temperature range. Pressure transmitters are available with a ¼-inch NPT male threaded process connection and an M12 quick-disconnect electrical connection. They have a linear 4–20 mA output with sensing ranges from 100–5000 psig. The UL508-listed SPTD25 series is engineered to meet many industrial, commercial, and original equipment manufacturer pressure measurement applications, such as process control and automation, hydraulic systems, engine monitoring, and machine tools.

AutomationDirect, www.automationdirect.com

Explosion-proof pressure switch

The B-series NEMA 7/9 explosion-proof pressure switch is now available with a 316 stainless-steel enclosure for demanding operating environments, including salt water spray. These switches are IP66 rated and are approved for use in most NEC Class 1 and 2 hazardous locations. Each pressure switch can be fitted with a variety of diaphragm materials (including Monel for NACE applications) or with an external diaphragm seal to resist caustic or corrosive media.

Ashcroft, www.ashcroft.com

Turbine flowmeters

The Star series liquid turbine flowmeters are suitable for measuring liquid flow in 11 sizes, covering a flow range of 0.35–650 GPM. The accuracy for this series is 1.0 percent and is repeatable to ±0.1 percent of reading. Industrial flow applications include fuel metering, well water, and gasoline. Flow rate indicators/totalizers and other electronic support equipment are available to accompany the series. A full line of high-precision turbine flowmeters with accuracies to ±0.1 percent is also available.

Hoffer Flow Controls, www.hofferflow.com

Wireless pressure gauge

 

The Rosemount wireless pressure gauge enables staff to remotely collect field data, keeping operators updated about changing field conditions and improving personnel safety by reducing manual operator rounds and field exposure. Mechanical gauges are plagued with quality and reliability issues. These issues are commonly associated with overpressure, vibration, corrosion, extreme temperatures, and accidental damage. Additionally, mechanical gauges are unable to communicate a device status.

The pressure gauges use piezoresistive sensor technology to deliver reliable pressure readings. With the flexibility to accommodate changing process conditions, the gauges also give up to 150 times more overpressure protection than traditional gauges. The field environment is safer with two layers of process isolation.

Bourdon tube gauges have traditionally been a mainstay for taking pressure readings in the field, but are limited to visual indication of process conditions when an operator is present. Bourdon tubes also use moving parts, which can break or wear over time due to use and vibration, causing inaccurate readings or the process to spill.

The wireless pressure gauge eliminates common weak points by removing the components that inhibit the device from reporting and displaying pressure. It has up to a 10-year life, which reduces maintenance costs and time. The 4.5-inch gauge face provides visibility in the field.

Emerson Process Management, www.emersonprocess.com

HART 7 transmitters

The One series 1XTXSW HART-capable transmitters provide programmable switching functionality for industrial process monitoring applications. The transmitters integrate HART 7–compatible 4–20 mA output and two solid-state programmable relays for monitoring temperature or pressure in safety, alarm, and emergency shutdown applications.

The hybrid transmitter-switch effectively replaces a gauge, a switch, and a transmitter—requiring only one connection to the process. This reduces costs and potential media leaks while increasing reliability. The series has no moving parts, which provides a highly repeatable and fully adjustable dead band switch that is suitable for applications with high cycle rates. Instrument response time is less than 100 milliseconds.

The transmitters are especially suitable for hazardous and harsh monitoring conditions with temperature extremes and high pressures that rapidly change, exhibiting pulsations, water hammer and thermal cycling, and other wear-inducing conditions. Mechanical switches, which have more moving parts, are more susceptible to such trauma, which affects reliability and requires more maintenance. Integrating sensors and solid-state relays in an explosion-proof transmitter enclosure protects them from environmental stress. The HART programming capability makes it easier to configure and maintain both the sensor and the switch, remotely, avoiding the need to open the enclosure in Division 1 areas. The 1X line also has worldwide hazardous location approvals for Class I, Divisions 1 and 2 (Zones 0, 1, and 2).

United Electric Controls, www.ueonline.com

HART communicators

The company’s HART communicator kits for hazardous areas use the TAB-EX series of Android tablets. The kits include the tablet, a HART modem, and the DevComDroid DD-based smart communicator app for Android. The app is a fully functional HART communicator. The entire DD library from FieldComm Group is included and regularly updated with a subscription. The user can also add new DDs. The app can perform full configurations of valves, multivariable devices, and complex devices, such as radar level and Coriolis flowmeters.

There is a Bluetooth wireless interface between the HART modem and the tablet. All components are certified for use in hazardous areas. Hazardous areas covered include CSA (Class 1, Division 1), ATEX, and IECEx. There is also a Windows version for Class 1, Division 2 hazardous areas.

ProComSol, www.procomsol.com

High-res sensor

The DLHR series low-pressure sensors work in pressure ranges of 0.5–60 inH2O. An advanced ASIC performs error compensation internally. The sensors have either I2C or SPI output interfaces with 16/17/18-bit resolution and accuracy better than 0.25 percent FSS BFSL. They can operate at variable supply voltage from 1.68–3.6 V. Devices are available in 0.5, 1, 2, 5, 10, 20, 30, and 60 inH2O pressure ranges, gauge and differential. The sensors are suitable for medical devices associated with low pressure, portable devices, battery-operated devices, remote sensing, HVAC application, spirometry, instrumentation, respiratory machines, and industrial controls.

All Sensors Corporation, www.allsensors.com