Best Pressure Gauges with Overpressure Protection

This article was originally published on March 13, 2019, and updated on July 16, 2025.

In many process industries, sudden pressure surges from water hammer, valve closures or equipment malfunctions can cause overpressure events that damage pressure gauges and lead to equipment failure and costly downtime. To reduce this risk, many systems rely on external pressure limiting valves (PLVs), which increase installation complexity and create potential leak paths. Ashcroft offers a smarter solution: pressure gauges with built-in overpressure protection.

With over 170 years of innovation behind us, Ashcroft understands the harsh realities of industrial applications and we engineer products that perform in the most extreme conditions. Read this article to learn about two pressure gauges that are designed with XRA Overpressure Protection to handle pressure surges internally, eliminating the need for external components and improving system reliability.

XRA: Built-In Overpressure Protection for Demanding Applications

The XRA overpressure feature is built into the pressure gauge. It helps the gauge handle extra pressure without damage, making it a good choice for processes where pressure changes are common. Knowing how the mechanism works can help you see why it’s useful for your process.

How the built-in protection functions

The XRA restricts the motion of the pressure gauge's Bourdon tube once the gauge reaches its full-scale pressure rating. This action changes the natural spring rate of the tube and prevents it from flexing further and allowing the gauge to absorb pressure up to 400–417% of its standard range without sustaining damage.

To help operators recognize when the gauge has entered unsafe territory, Ashcroft includes a red overpressure band on the dial. The dial is divided into two regions:

• The measurement range, which shows normal operating pressure with standard graduation marks.
• The overpressure range, clearly marked in red and labeled “Overpressure,” visually indicates that the system has exceeded its intended operating range.

To choose the correct pressure gauge range for your process, you will need to consider the standard operating pressure of the gauge and the potential pressure spikes that may occur in the process.

Two Pressure Gauges with One Overpressure Protection Solution

Ashcroft offers two robust pressure gauge models equipped with the XRA Overpressure Protection option—each designed to perform in high-risk, high-pressure environments. Whether you need a durable gauge for general process applications or a solution for corrosive or high-vibration conditions, we have you covered.

Here’s a closer look at the Ashcroft®T6500 Pressure Gauge and the Ashcroft®1209 Pressure Gauge to illustrate how they deliver reliable, built-in protection against damaging pressure surges.

Overpressure Protection in the T6500 Pressure Gauge

The Ashcroft® T6500 Pressure Gauge with XRA is specifically designed for rugged industrial and process applications where pressure spikes are frequent and unpredictable.

Key Features:

• Overpressure resilience up to 400% of the gauge’s measurement range
• Built-in XRA mechanism that protects the Bourdon tube during extreme pressure events
• ±1.0% accuracy within the measurement portion of the dial
• The red overpressure indicator band clearly shows when the system pressure is excessive
• Eliminates or reduces the need for external PLVs, reducing installation costs and potential leak paths
• Available in 100 mm or 160 mm sizes

This gauge is ideal for applications like reciprocating pumps, compressors and systems prone to water hammer, where protecting measurement instruments is crucial to uptime and safety.

Figure 1: The Ashcroft® T6500 Pressure Gauge

Overpressure Protection in the 1209 Pressure Gauge

For demanding environments that require equally rugged instrumentation, the 1209 pressure gauge with XRA offers excellent performance and extended gauge life.

Key Features:

• XRA protects up to 417% overpressure
• Durable 316L stainless steel case, ring, and wetted parts for corrosion resistance
• 4½-inch dial size with ±0.5% accuracy (ASME B40.100 Grade 2A)
• Optional PLUS!™ Performance or liquid fill for enhanced resistance to shock and vibration
• Solid front design with pressure relief back for operator safety

The 1209 is particularly well suited for high-cycle, high-vibration applications like:

• Offshore oil rigs
• Chemical and petrochemical plants
• Food and beverage processing
• Pulp and paper mills
• Power generation facilities
• OEM machinery skids

Figure 2: The Ashcroft® 1209 Pressure Gauge with XRA

Why Built-In Overpressure Protection Is Better

In many systems, pressure limiting valves are used to protect instrumentation. While they work, they introduce added components, added cost and added risk. Ashcroft’s XRA option eliminates the need for external protection by integrating it into the gauge itself. This results in:

• Fewer leak paths
• Simplified installation
• Reduced maintenance
• Lower long-term costs

Ready to learn more?

Knowing that you have options when choosing pressure gauges that may need overpressure protection, you are in a better position to select the best solution for your application. If you want more information about pressure gauges, here are some additional articles that may be of interest to you:

• How Do I Select the Right Pressure Gauge Range?
• Choosing the Right Pressure Gauge Dial Size
• Solid Front vs. Open Front Pressure Gauges
• Selecting the Right Pressure Gauge for Ultra-High-Pressure Applications

Contact us anytime to talk to one of our industry experts and get all your pressure gauge questions answered. In the meantime, check out our pressure gauge selection tool to help you find the best instrument for your needs.