The WIKA IS-3 Pressure Transmitter is an industrial pressure measurement instrument developed for applications with demanding operating conditions, especially those requiring certified protection for hazardous areas.

It converts applied pressure into an electrical signal that can be transmitted to a PLC, DCS, or other compatible process monitoring system. The IS-3 is available in a broad range of pressure configurations, making it suitable for general industrial pressure measurement as well as specialized high-pressure applications.

One of its defining features is its construction: the wetted parts are made of stainless steel and fully welded, avoiding internal sealing elements in the wetted section. This design helps reduce potential leakage paths and supports use with a wide variety of process media, subject to material compatibility.

The IS-3 is also available with different process connections, electrical connections, pressure ranges, and enclosure options. For installations involving hazardous gases, combustible dust, or demanding process conditions, the exact model configuration and applicable approvals must be checked before installation.

Key Features

1. Wide Pressure Measurement Range

The IS-3 supports measuring ranges from 0–0.1 bar to 0–6,000 bar (approximately 0–15,000 psi at the upper end), depending on the selected configuration.

This broad range allows the product family to cover applications from low-pressure monitoring to specialized high-pressure measurement. The appropriate measuring range should be selected based on normal operating pressure, expected pressure peaks, and the required measurement resolution.

2. Hazardous-Area Approvals

The IS-3 series offers configurations with approvals such as ATEX, IECEx, FM, and CSA for use in specified hazardous environments.

These approvals are particularly relevant where flammable gases, vapors, or combustible dust may be present. Approval availability depends on the particular version, so the full model code and certification requirements must be checked against the installation's hazardous-area classification.

3. Fully Welded Stainless Steel Construction

All wetted parts are manufactured from stainless steel and fully welded, without internal sealing elements in the wetted section.

This construction is beneficial in applications where leakage prevention, mechanical robustness, and reliable long-term pressure measurement are important. However, the suitability of the selected materials still depends on the process medium, temperature, and pressure.

4. 4–20 mA Analog Output

The IS-3 provides a 4–20 mA analog output, allowing measured pressure to be transmitted to compatible industrial control and monitoring equipment.

This signal format is commonly used in process automation and can support centralized pressure monitoring, alarm handling, and process control. The electrical supply, load resistance, and wiring must meet the specifications of the selected version.

5. Flush-Diaphragm Process Connections

Selected configurations are available with flush-diaphragm process connections. These are particularly useful for viscous, contaminated, or solids-containing media, where conventional pressure ports may be more susceptible to deposits or blockage.

A flush-diaphragm configuration can also be useful where residue-free cleaning is required, provided the selected process connection and materials are appropriate for the application.

6. Stainless Steel Housing and Environmental Protection

The robust stainless steel case provides at least IP65 ingress protection, with IP68 versions available in selected configurations.

An optional field case is also available for demanding environments and is designed to resist exposure to substances such as acids, bases, oils, and solvents under the specified conditions. The required enclosure and connection type should be selected according to the actual installation environment.

Suitable Applications

The IS-3 is intended for industrial pressure measurement where reliability, process compatibility, and hazardous-area requirements are important.

1. Chemical and Petrochemical Processing

Suitable for monitoring pressure in process lines, vessels, and associated equipment. Where the process involves aggressive chemicals or elevated temperatures, confirm the compatibility of the wetted materials and sealing arrangement.

2. Oil and Gas Facilities

Can be used for pressure monitoring in suitable oil and gas process systems, including installations where hazardous-area certification is required.

The pressure range, process connection, electrical interface, and area classification should be checked together before specifying the transmitter.

3. Natural Gas and Industrial Gas Systems

Suitable for measuring gas pressure in industrial systems where continuous pressure signals are required for process monitoring or control.

For hazardous gas environments, the selected approval and installation method must comply with the applicable site requirements.

4. High-Pressure Equipment

The high-pressure versions of the IS-3 support measuring ranges up to 6,000 bar, making them suitable for selected high-pressure applications.

These may include specialized pressure testing equipment and high-pressure industrial machinery. The pressure range alone is not sufficient to establish suitability: the process connection, overpressure limits, temperature, and pressure cycling conditions must also be considered.

5. Industrial Machinery and Manufacturing

Suitable for pressure monitoring in machine-building applications, hydraulic systems, and industrial equipment where a continuous electrical measurement signal is required.

For hydraulic applications, verify that the selected measuring range and process connection can withstand the expected working pressure and transient pressure peaks.

6. Compressors and Compressor Systems

The IS-3 can be used in suitable compressor installations to monitor operating pressure and provide a signal to the control system.

The model configuration should be selected according to the gas or fluid being measured, the operating pressure, and any hazardous-area requirements.

7. Viscous or Contaminated Media

The flush-diaphragm versions are particularly relevant when the medium may be viscous, adhesive, or contain solids that could accumulate around a conventional pressure port.

Where cleaning is important, confirm that the selected diaphragm, process connection, and material configuration meet the required hygiene or cleaning conditions.

Technical Highlights & Selection Considerations

1. Select the Correct Pressure Range

The IS-3 family covers a very wide range of pressures, but each individual transmitter is configured for a specific measuring range.

Before ordering, confirm:

• Normal operating pressure.
• Maximum expected operating pressure.
• Potential pressure spikes or pulsations.
• Required gauge, absolute, or compound pressure measurement.
• Required engineering units, such as bar or psi.

The selected measuring range should suit the actual operating conditions. Do not choose a transmitter based only on its maximum pressure rating.

2. Confirm the Hazardous-Area Certification

For installations in potentially explosive atmospheres, the required certification is a critical selection factor.

Check the site classification, gas or dust group, equipment protection level, temperature class, and required regional approvals. A transmitter family may offer multiple approval options, but an individual unit is only suitable when its own certification matches the installation requirements.

For intrinsically safe versions, the power supply and associated safety equipment must also comply with the applicable documentation.

3. Choose the Appropriate Process Connection

The IS-3 is available with various threaded and specialized process connections. The correct choice depends on the existing pipework, pressure rating, installation standard, and medium.

For replacement orders, compare the original connection type, thread size, sealing method, and pressure rating. A similar-looking thread does not necessarily guarantee mechanical compatibility or a leak-tight installation.

4. Consider Medium Temperature and Material Compatibility

The permissible medium temperature depends on the selected version, process connection, sealing materials, and hazardous-area configuration. Certain configurations support medium temperatures up to +200 °C.

For aggressive chemicals, hot process media, or unusual gas mixtures, confirm the full specification rather than relying on the maximum temperature published for the product family.

5. Determine Whether a Flush Diaphragm Is Needed

A conventional process connection may be suitable for clean, low-viscosity fluids and gases. However, viscous, contaminated, or solids-containing media may benefit from a flush-diaphragm design.

Consider the medium's tendency to build up deposits, the cleaning procedure, and the required process connection before choosing the configuration.

6. Check the Electrical Configuration

The standard IS-3 uses a 4–20 mA output and typically operates from a 10–30 V DC supply. Versions with a field case have different minimum supply requirements, and permissible load depends on the supply voltage and wiring.

For replacement projects, verify the supply voltage, wiring, output signal, connector or cable arrangement, and required associated equipment.

FAQ

1. What is the WIKA IS-3 Pressure Transmitter used for?

The WIKA IS-3 measures industrial process pressure and converts it into an electrical signal for monitoring and control. It is particularly suited to demanding applications, including chemical processing, oil and gas, industrial machinery, and installations requiring hazardous-area approvals.

2. What is the maximum pressure range of the WIKA IS-3?

The product family offers measuring ranges up to 6,000 bar (approximately 87,000 psi). The exact measuring range and allowable overpressure depend on the selected version and process connection.

3. Does the WIKA IS-3 support hazardous-area applications?

Yes. Selected configurations offer ATEX, IECEx, FM, and CSA approvals. The exact approval must match the installation's hazardous-area classification and applicable electrical safety requirements.

4. What output signal and power supply does the IS-3 use?

The IS-3 provides a 4–20 mA analog output. The standard version generally operates on 10–30 V DC, while field-case versions have different supply requirements. Always verify the specifications for the exact model.

5. Can the WIKA IS-3 measure viscous or contaminated media?

Yes. Selected versions with a flush-diaphragm process connection are designed for viscous, contaminated, and solids-containing media. Confirm the diaphragm material, process connection, pressure rating, and medium compatibility before selecting the instrument.