### **PR235 Multi-Function Calibrator Review: Field Test Confirms It Replaces Three Devices, Doubles Maintenance Efficiency**

In the relentless environment of field instrumentation, efficiency isn't just a goal—it's a necessity. Every minute saved during a calibration routine translates directly into reduced downtime, lower costs, and increased plant availability. For years, the standard field kit for a comprehensive maintenance engineer involved a cumbersome ensemble: a separate pressure calibrator, a HART communicator, and a multimeter for loop checks. Juggling these three devices is inefficient, prone to error, and a physical burden.

The promise of a multi-function calibrator like the PR235 is to consolidate this trio into a single, robust unit. But does it live up to the hype? After putting the PR235 through its paces in a real-world plant environment, the conclusion is clear: it doesn’t just meet expectations; it redefines them. This isn't just an incremental improvement; it's a paradigm shift in field maintenance workflow.

#### **The "One Device to Rule Them All" Promise Delivered**

The core claim is replacing three devices. The PR235 delivers this through its integrated functionality:

1.  **High-Accuracy Pressure Measurement and Sourcing:** With a built-in pneumatic pump and an accurate pressure sensor, the PR235 handles the core task of simulating and measuring pressure for transmitters, gauges, and switches. It eliminates the need for a standalone pressure calibrator and a separate hand pump.

2.  **Full HART Interrogation and Configuration:** This is the killer feature. Unlike a standard pressure calibrator that can only read the loop current, the PR235 has a full HART modem integrated. This allows you to not only measure the 4-20mA signal but also to read the transmitter's digital PV, re-range it, perform trim operations, and diagnose problems—all from the same screen. It completely replaces the need to carry a dedicated HART communicator.

3.  **Advanced Multimeter and Loop Source Functions:** Beyond pressure and HART, it provides precise measurement of mA, V, and resistance. Its 24V loop power supply with simulate and measure functionality allows for complete loop troubleshooting and transmitter simulation without any additional equipment.

#### **The Efficiency Leap: A Step-by-Step Field Scenario**

The true value is revealed in a direct comparison of a common task: troubleshooting a problematic pressure transmitter.

**The Old Way (Three Devices):**

1.  Grab the HART communicator, connect it in parallel, and read the digital PV and diagnostics.

2.  Disconnect the communicator. Grab the pressure calibrator and hand pump, connect them to the transmitter impulse line.

3.  Apply pressure, then reconnect the HART communicator to see the digital output at that pressure.

4.  To check the loop current, you might need the multimeter.

5.  Each step involves fumbling with different devices, wires, and connections, significantly increasing the time and risk of error.

**The New Way (PR235):**

1.  Connect the PR235's test leads to the transmitter terminals for power and communication.

2.  Connect the integrated pressure pump to the transmitter's impulse line.

3.  On one single screen, you can now see: the **mA loop current**, the **HART digital PV**, and the **actual pressure** you are applying with the pump.

4.  You can apply pressure, immediately observe all three key parameters synchronously, and even use the on-screen HART menu to re-range the device without ever disconnecting a single wire.

This seamless integration is what **doubles the efficiency**. The time savings are not just in the measurement but in the drastic reduction of setup, connection changes, and the mental load of switching between devices.

#### **Beyond Hardware: The Software That Seals the Deal**

Like its predecessor discussed in our previous article, the PR235’s power is magnified by its software. The unit can store thousands of calibration results. After a day in the field, you connect via Bluetooth or USB, and all data is automatically uploaded to calibration management software, which generates audit-ready certificates instantly. This eliminates manual data transcription errors and saves hours of administrative work, contributing massively to the overall efficiency gain.

#### **Robust Design for the Real World**

A consolidating device is useless if it's fragile. The PR235 is built for field use. Its IP54 rating protects against dust and water splashes, the battery easily lasts a full shift, and the interface is designed for use with gloves. The fact that you only need to carry, protect, and manage one device instead of three dramatically simplifies logistics and improves reliability.

#### **Conclusion: A Compelling Investment in Modernization**

The PR235 is more than a calibrator; it's a force multiplier for instrumentation teams. While the initial investment is higher than a basic pressure calibrator, the Return on Investment (ROI) is calculated through:

*   **Reduced Capital Expenditure:** Buying one device instead of three.

*   **Dramatically Lower Downtime:** Cutting calibration and troubleshooting time by half.

*   **Elimination of Data Errors:** Automated data collection improves compliance.

*   **Enhanced Technician Productivity:** Reducing physical and cognitive load, allowing them to complete more tasks safely and accurately.

For any team serious about modernizing their maintenance practices, improving efficiency, and embracing the principles of Industry 4.0, the PR235 isn't just an option—it's an essential tool that delivers on its ambitious promise. It truly sets a new standard for what a field calibrator should be.