Modern process automation has made the use of smart instruments the norm in the world. The HART Calibrator is an essential tool for engineers and technicians to deal with such devices. Be it in a power plant, an oil refinery, or a highly sophisticated calibration lab, it is imperative to know how to interface with the Highway Addressable Remote Transducer (HART) protocol to keep the system in integrity.
With the help of sophisticated HART calibrator software, industries are now able to go beyond the limited scaling of field devices in doing deep diagnostics and digital configuration to ensure the proper communication between field devices and control systems.
What is a HART Calibrator?
A HART Calibrator is a highly accurate handheld or bench top instrument which is used to configure, test, and calibrate intelligent field instruments (such as pressure or temperature transmitters) which operate using the HART protocol.
How the HART Protocol Works
The HART protocol is special since it follows a Digital-over-Analog approach. It overlaid a high frequency digital signal on top of the normal 4-20mA analog loop.
- The Analog Signal communicates the primary variable (e.g., tank level).
- The Digital Signal communicates additional data like device status, diagnostics, and secondary variables.
Standard Calibrator vs. HART Calibrator
There is a standard calibrator that just measures or sources the 4-20mA signal. A HART Calibrator may be able to do both, and also communicate to the microprocessor inside the device, such as the Upper Range Value (URV) or Lower Range Value (LRV).
HART Calibrator Important Operabilities.
- Communicating with Field Devices: Reaching the inside menu of the device.
- Smart Transmitters configuration: Re-ranging, unit conversion (e.g., Bar to PSI), and tagging.
- Loop Calibration: Checking that the digital output is equal to the analog output.
- Reading Diagnostics: Diagnostic checking of sensor errors or equipment malfunctions.
- Data Documentation: Compliance: Automatically record As-Found and As-Left data.
How to Use a HART Calibrator?
A correct use of a HART calibrator is a combination of software and electrical safety.
Pre-Calibration Requirements
- Power Supply: Check that there is a power supply of 24V DC on the loop.
- Loop Resistance: A 250- ohm resistor is required in the loop so the HART digital signal can be noticed by the calibrator.
- Checks of Safety: This is to ensure that the area is safe (particularly where there is an explosive atmosphere) and that the control room is informed that the loop is in the Test Mode.
The following are the steps taken to use a HART Calibrator.
- Connecting: Parallel The calibrator leads can be connected in parallel with the device or across the 250-ohm resistor.
- Setting up Communication: Activate Communication. The calibrator will search the loop to identify the connected device.
- Parameters configuration: Use the menu to check the LRV, URV, and Damping values.
- Doing Calibration: Drive a known real-world input (e.g., 50 PSI) and verify whether the digital and analog outputs are equal.
- Save Results: Save the data to internal memory to be uploaded later into your HART calibrator software.
HART Calibrator Software: Enhancing Calibration Efficiency
The connection between the field work and office management is provided by modern HART calibrator software. This software enables the technicians to:
- Install canned calibration paths to the handheld.
- Calibration certificates are automatically generated by the professionals.
- Full NABL/ISO compliance audit trail.
- ManageDevice Descriptions(DD files) to keep in pace with the most recent field instruments.
HART Communicator 475 – Industry Standard Explained
The HART Communicator 475 has long been regarded as the powerhouse of the market. It was developed to work with the HART and Foundation Fieldbus devices, and became the gold standard of field technicians.
- Key Features: Huge battery duration, color interface, and intrinsic safety (IS) ratings in dangerous areas.
- Applications: Large-scale industrial projects are frequently used in maintenance and commissioning.
HART Communicator Emerson – Trusted Solution for Smart Devices
Its HART Communicator Emerson series (with the more recent AMS Trex Device Communicator) has a high level of reliability because it is a pioneer in the protocol.
- Why it is trusted: It is integrated into the world-class field instruments of Emerson, as well as the AMS Device Manager.
- Diagnostics: These devices are known to have the type of mobile applications called ValveLink and the ability to diagnose and create an anticipation of failure of any device prior to its occurrence.
HART Calibrator vs. HART Communicator
| Feature | HART Communicator | HART Calibrator |
| Primary Goal | Configuration & Diagnostics | Measuring/Sourcing & Configuration |
| Sourcing Signal | Cannot source 4-20mA/Pressure | Can source/measure physical signals |
| Use Case | Changing a tag or checking an error | Verifying accuracy and trimming the sensor |
Combined Usage: Most modern high-end tools are now “Documenting HART Calibrators,” which combine both functions into one powerful device.
Applications of HART Calibrators Across Industries
- Oil & Gas: The process of calibration of the high-pressure transmitters in offshore rigs.
- Power Plants: Control of temperature and flow sensors of steam turbines.
- Chemical & Petrochemical: Dosage and reactor monitoring.
- Pharmaceutical: Ensuring that batches are calibrated and FDA-compliant.
How ITPL Provides Complete HART Calibration Solutions
In the case of Isothermal Technology Private Limited (ITPL), we know that smart instruments need smart calibration tools. We provide:
- Expert Consulting: Assistance in making a decision between a standalone communicator and a documenting calibrator.
- Premium Supply: We sell various HART-compatible calibrators and communicators that are suitable for the Indian market.
- Integrated Systems: Our solutions integrate with calibration benches and management software for a paperless laboratory experience.
- Local Support: ITPL offers the training and after sales support needed to make sure your staff are well trained on the use of the HART technology.
FAQs on HART Calibrators
Q1. What is the purpose of a HART calibrator?
Ans: It is applied to test smart transmitters, communicating with their internal microprocessors and at the same time measuring their analog input.
Q2. What is the difference between a HART communicator and a HART calibrator?
Ans: The only thing that a communicator does is to talk to the device to alter settings. The physical signal (such as pressure or mA) can actually be measured or sourced by a calibrator to check its accuracy.
Q3. Is it possible to store calibration records using HART calibrator software?
Ans: Yes, with advanced software, you can be able to upload the field data to a central database and generate certificates and trend analysis.
Q4. Is the HART communicator 475 still popular?
Ans: Although some of them are still in service, the industry is slowly changing to more advanced units such as Emerson AMS Trex, which provides better connectivity and high-speed processors.
Conclusion
The selection of an appropriate HART Calibrator is critical when any facility wants to minimize downtime and to guarantee the accuracy of measurements. Using the appropriate hardware along with a strong HART calibrator software, you can be sure that your facility is working correctly and your smart devices are operating on their highest performance.
Need an effective HART calibration? See the variety of process calibrators offered by Explore ITPL, and allow our specialists to make your calibration process more efficient.
