Process isolators

Galvanic isolation for instrumentation and control signals

The signal and process isolators They allow for the electrical isolation of sensors, transmitters, measuring equipment, PLCs, and data acquisition systems. Galvanic isolation prevents direct electrical connection between the input and output, while maintaining the transmission of the measurement signal.

These devices are used to eliminate ground loops, reduce interference, protect control system inputs, and improve signal stability in industrial facilities.

Input and output signals

The range includes isolators and converters for various analog and instrumentation signals:

• Current signals: 0-20 mA, 4-20 mA and other continuous intensity ranges.
• Voltage signals: 0-10 V, ±10 V, mV and DC voltage ranges.
• Resistive signals: potentiometers, resistors and position sensors.
• Temperature signals: PT100, PT1000 and other resistive sensors.
• Special signals: PWM, AC/DC voltage and current, and high voltage applications.

There are also configurable universal devices that allow different input and output ranges to be adapted to the needs of each installation.

Available features

In addition to isolating a signal between the input and output, other conditioning functions can be performed:

• 1:1 Insulation: Reproduction of the input signal while maintaining galvanic isolation.
• Signal conversion: transformation between current, voltage, resistance or other standardized signals.
• Duplication: one input and two isolated outputs to send the same measurement to two systems.
• Multiple distribution: an input signal with four or more independent outputs.
• Multi-channel isolation: several independent channels integrated into a single box.

When is a signal isolator needed?

Galvanic isolation is recommended when there are potential differences between equipment, ground loops, electrical noise, or unstable signals. It is also necessary when the same measurement must be sent to multiple receivers without the circuits interfering with each other.

Process isolators are commonly used in industrial automation, machinery, water treatment, energy, photovoltaic installations, chemical processes, SCADA systems, and data acquisition equipment.

How to select the right insulator

To select the equipment, it is necessary to know the type and range of the input signal, the required output signal, the number of channels or outputs, the type of power supply, and the level of isolation.

Aspects such as accuracy, response time, whether the input or output is active or passive, auxiliary power supply, and mounting format should also be checked.

GUEMISA offers technical advice for selecting the galvanic insulator, signal duplicator or converter suitable for each sensor, installation and control system.

What is the difference between an isolator and a signal converter?

An isolator reproduces a signal while maintaining galvanic isolation between circuits. A converter transforms the input signal into another type or range of output signal. Many devices can perform both functions simultaneously.

What is the difference between an isolator and a doubler?

An isolator typically has one input and one output. A duplicater receives a signal and generates two independent outputs, allowing the same measurement to be sent to two PLCs, indicators, recorders, or data acquisition systems.