Pressure Transmitters

What Are the Benefits of Pressure Transmitters?

With improved digital performance, measurement accuracy, and overpressure protection, DPharp pressure transmitters contribute to enhanced product quality.

Digital Performance

Other pressure sensor technologies require an analog-to-digital conversion before the signal can be processed, introducing additional errors. In Yokogawa’s pressure transmitters, the DPharp sensor directly outputs a digital signal, eliminating the need for analog-to-digital conversion and improving performance.

Accuracy Under All Operating Conditions

Fluctuations in static pressure and temperature cause errors in differential pressure measurement. Analog sensors can only measure DP and sensor temperature and therefore can only compensate for temperature effect.

Yokogawa’s DPharp digital pressure sensor measures the differential pressure (DP), static pressure (SP), and sensor temperature from a single sensor. Given these three pieces of process data, our differential pressure transmitters compensate the DP measurement for temperature effect and static pressure effect in real-time. This compensation is referred to as Dynamic Compensation and improves DP measurement accuracy.

Learn more about Dynamic Compensation.

What Happens When a Transmitter Sensor Is Exposed to Overpressure?

Overpressure events such as incorrect sequencing of a manifold during start-up or shutdown and process upsets can damage analog sensors, requiring the transmitter to be recalibrated - or even replaced - in order to return it to normal operations.

The simple, robust design of Yokogawa's DPharp pressure sensor makes it less susceptible to overpressure events. A mechanical system within the transmitter provides additional overpressure protection by equalizing the excessive pressure before it reaches the sensor. Once it returns to normal operating pressure, the transmitter returns to operation within the defined accuracy and stability specifications with no need for recalibration. The Yokogawa DPharp sensor has a more significant operational envelope compared to an analog sensor, allowing you to run your control loop at your desired set-point regardless of process conditions.

How to Reduce Total Cost of Ownership for Field Instrumentation?

DPharp pressure transmitters are certified to high safety standards as well as international standards and require fewer calibrations. Multi-sensing and universal mounting features eliminate the need to manage multiple transmitters, reducing total maintenance costs.

Safety as Standard

At Yokogawa, safety is never an option. All Yokogawa pressure transmitters are designed and certified to IEC61508:2010 Parts 1 through 7 and IEC61511:2004 Parts 1 through 3 by Exida^® and TÜV Rheinland^®.

As standard, all Yokogawa transmitters are certified for single transmitter use in SIL2 safety applications and dual transmitter use in SIL3 safety applications. The same transmitter can be used for both process control and safety applications. Managing two separate transmitter models is no longer necessary, reducing spares inventory and simplifying daily operations.

Extended Calibration Check Intervals

When devices are initially installed, they operate at peak performance, but what happens after they are running under various process conditions and poorly managed or maintained?

Changing operating conditions can cause transmitters to drift to the point where they are no longer able to make accurate measurements for the process loop they are installed in, resulting in poor quality or an impact to product yields. This requires a calibration check interval to ensure you’re operating within desired error limits.

The DPharp sensor has an unconditional long-term stability guarantee of ±0.1% up to 15 years under all operational conditions, reducing calibration frequencies. As you gain experience with these transmitters, the interval between calibration checks is extended. Long-term this can help reduce your maintenance cost by up to 34%. Spend your time where it is needed.

Independent Third-Party Verification

With the rapid globalization of markets, numerous international standards and approvals are becoming necessary. Yokogawa pressure transmitters have acquired various international certifications including FM, CSA, ATEX, IECEx, INMETRO, KOSHA, EAC, and NEPSI.

Multi-Sensing in DP Applications

Other suppliers' transmitters use analog sensors, which require two separate transmitters for any application that needs both differential pressure (DP) and static pressure (SP) measurements.

Yokogawa's differential pressure transmitter features our multi-sensing DPharp sensor, which can measure both process variables (DP and SP) with a single transmitter, saving you the cost of a gauge pressure transmitter as well as the manifold, piping, wiring, I/O, construction, and engineering man-hours associated with it. With our DP transmitter, there are fewer devices to manage, maintain and calibrate, lowering overall lifecycle costs.

Standard Communication Protocol

Yokogawa transmitters support all industry-standard field device communication protocols. Interoperability and interchangeability can be ensured. Use all the same tools and work procedures as before. Yokogawa transmitters are available with analog 4 to 20mA signal with either BRAIN^® digital protocol or HART^® digital protocol; Low Power analog 1 to 5 VDC with HART^® digital protocol; or all digital FOUNDATION^® Fieldbus or PROFIBUS^® PA protocol.

Universal Mounting

Pressure transmitters on the market have several different flange configurations depending on the medium being measured (gas or liquid). This requires plants that process both mediums to maintain a stock of both types of configurations.

Yokogawa's pressure transmitters offer a universal mount that can be configured to handle either gas or liquid; reducing your inventory of replacement transmitters.

How Are Pressure Transmitters Built?

DPharp pressure transmitters are engineered to withstand the harshest process conditions, featuring a rugged construction design and less susceptibility to overpressure events for a longer-lasting transmitter.

Rugged Construction

Harsh environments can reduce the life of your instrumentation, causing maintenance issues and plant downtime. Yokogawa’s ruggedly constructed pressure transmitters feature a four-bolt pressure-retaining design, Teflon^® coated 316L stainless steel flange gasket, and a dual seal certified to ANSI/ISA 12.27.01. These design features extend the life of your transmitter, increasing plant availability.

How Does Overpressure Protection Work?

During improper manifold sequencing, startup and shutdown conditions, or process upsets, overpressure can occur. The simple, robust design of Yokogawa's DPharp pressure sensor makes it less susceptible to overpressure events. A mechanical system within the transmitter provides additional overpressure protection by equalizing the excessive pressure before it reaches the sensor. Once stable process conditions return, these features enable the transmitter to return to normal operation within the published specifications.

Local Indicator

Easy to read indicator provides all the information you need. The indicator can display any of the variables measured (DP, SP, Capsule temperature); alarm codes with short text; and a sweeping bar graph to give a graphical representation of the process. Fully programmable, the indicator is customizable for your needs. Unlike other suppliers' transmitters, the indicator is not driven off the 4 to 20mA analog signal, but, exists as a separate circuit allowing the display to operate independently from the output signal.