Industrial electric actuators for precise automated valve control. Part-turn, multi-turn and linear options with ATEX certification, modulating control and failsafe mechanisms.
An electric actuator is a device that converts electrical power into mechanical motion to operate a valve. At their core, electric actuators contain an electric motor and gearbox that work together to produce the torque needed to open, close or regulate a valve. The motor spins at high speed, and the gearbox reduces this speed while multiplying the torque, allowing a compact device to operate valves of virtually any size.
The basic principle is straightforward: electrical power enters the actuator, energizing the motor which begins to spin. This rotational motion passes through a mechanical gearbox — a series of interlocking gears that reduce speed and increase torque. The output of the gearbox is then connected to the valve stem or ball mechanism. For part-turn applications (like ball valves), the actuator rotates 90 degrees to open or close. For multi-turn applications (like gate valves), the actuator provides continuous rotation to drive a threaded stem. Modern actuators also include limit switches that detect when the valve is fully open or closed, allowing the motor to stop automatically and prevent overload.
Advanced electric actuators go beyond simple on/off operation. Many feature potentiometer feedback systems that constantly measure valve position, allowing for modulating (proportional) control where the valve can be positioned anywhere between fully open and fully closed. This makes electric actuators ideal for flow regulation, temperature control and process applications where precise positioning is essential.
Part-turn (or quarter-turn) electric actuators are designed for valves that operate with a 90-degree rotation, such as ball valves and butterfly valves. These compact, efficient actuators are ideal where space is limited and quick operation is required. Part-turn actuators are available in a wide range of sizes and torque outputs, from small 10Nm units for compact ball valves up to several hundred Nm for large industrial butterfly valves. They can be fitted with manual overrides, allowing manual operation if power is lost, and many feature visual position indicators showing whether the valve is open or closed.
Multi-turn electric actuators provide continuous rotational motion, making them suitable for gate valves, globe valves and any valve with a threaded stem that requires multiple rotations to fully open or close. These actuators drive the valve stem through a mechanical screw-and-nut mechanism. Multi-turn actuators come in a variety of sizes depending on the valve and the duty, and they're essential for large industrial valves and isolation applications where high torque is required to operate stiff manual stems.
Linear (or sliding stem) electric actuators convert rotational motor output into linear motion, moving along a straight line rather than rotating. These actuators are used for control valves, diverter valves and other applications requiring linear stem travel. Linear actuators provide smooth, controllable motion and are commonly used in modulating applications where proportional flow regulation is needed.
Modern electric actuators are packed with features for reliability, safety and ease of operation.
Most electric actuators include a manual override (key or handwheel) allowing manual operation if power is lost, ensuring you can always operate your valve when needed.
A clear mechanical indicator showing whether the valve is fully open, fully closed or anywhere in between. Essential for safety and operational oversight.
Electric heating element inside the actuator body for cold-weather operation, ensuring smooth function even in sub-zero temperatures on outdoor installations.
Modern brushless DC motors offer superior reliability, longer service life, and require virtually no maintenance compared to older brush-type motors.
Single-phase or three-phase AC, or DC power — select the voltage that matches your control system. Available in 24V, 110V, 230V, 380V and other standards.
Integrated limit switches automatically detect when the valve is fully open or fully closed, stopping the motor and preventing mechanical damage or overload.
Continuous position feedback via a built-in potentiometer allows monitoring of valve position and enables modulating control for proportional valve operation.
Standard industrial 4-20mA analogue signal output for integration with building management systems, PLCs, SCADA and other control infrastructure.
Simple two-position operation: a signal tells the actuator to fully open or fully close the valve, with limit switches stopping the motor when the end position is reached. This is the most basic and most common control mode, suitable for isolation applications and simple flow switching.
Advanced proportional control where the actuator position follows a control signal, allowing the valve to be positioned anywhere between fully open and fully closed. The potentiometer continuously reports position, and the control system can adjust the motor speed to achieve the desired opening. Ideal for flow regulation, temperature control and any application requiring precise multi-position operation.
Critical applications require failsafe mechanisms. Options include:
For hazardous areas in oil, gas, chemical and petrochemical industries, we supply ATEX-certified electric actuators meeting all EU directives for use in explosive atmospheres. ATEX II 2G/2D certified actuators are available with flame-proof or increased safety enclosures, certified for use in Zone 1 and Zone 2 hazardous areas.
Electric actuator enclosures are rated for environmental protection:
We supply electric actuators from all major manufacturers, including compact smart actuators, general-purpose industrial ranges, and heavy-duty offshore-certified units. Whether you need entry-level commodity actuators or specialist ATEX-certified equipment, we can source and supply from a vast range of approved suppliers.
Our range includes compact modulating actuators ideal for BMS integration, on/off actuators for simple isolation duties, heavy-duty industrial ranges for large valves and harsh environments, and specialist ATEX-certified actuators for hazardous areas. We also carry specialist units including geared limit switches for multi-turn applications, battery backup modules for failsafe operation, and manual override attachments.
| Type | Torque Range | Input Power | Control Signal | Position Feedback | Protection |
|---|---|---|---|---|---|
| Part-Turn (Compact) | 10–50 Nm | 24V DC / 110V AC | On/Off | Limit switches | IP65 |
| Part-Turn (Standard) | 50–200 Nm | 110V / 230V AC | On/Off, Modulating | Potentiometer, 4-20mA | IP65, IP67 |
| Part-Turn (Heavy-Duty) | 200–500 Nm | 230V / 380V AC | On/Off, Modulating | Potentiometer, 4-20mA | IP67, IP68 |
| Multi-Turn (Industrial) | 100–2000 Nm | 110V / 230V / 380V AC | On/Off, Modulating | Potentiometer, 4-20mA | IP65, IP67 |
| Linear Actuator | 500–5000 N (force) | 24V DC / 110V AC / 230V AC | On/Off, Modulating | Potentiometer, 4-20mA | IP65, IP67 |
| ATEX-Certified | 50–500 Nm | 24V DC / 110V AC / 230V AC | On/Off, Modulating | Potentiometer (certified) | IP67 (certified) |
Electric actuators are used wherever automated valve control is required. Here are the most common applications:
WRAS-approved electric actuators on isolation and control valves in municipal water treatment plants and distribution networks.
Modulating actuators on three-way mixing valves in boiler systems, heat pump installations and chilled water circuits for precise temperature control.
On/off and modulating control of isolation, diverter and throttling valves in chemical plants, refineries and manufacturing facilities.
ATEX-certified electric actuators for pipeline isolation, manifold control and topside equipment on offshore platforms and onshore facilities.
Modulating 3-way and 2-way electric valves with BMS-compatible control signals for HVAC system integration and energy efficiency.
Spring-return or battery-backed actuators in fire suppression, safety shutoff and critical isolation applications requiring fail-safe operation.
Ball valves and butterfly valves require part-turn actuators (90-degree rotation). Gate valves, globe valves and other multi-position valves require multi-turn actuators. If you already have a manual valve and want to automate it, identifying the valve type is the first step.
Actuator torque must exceed the torque needed to operate your valve. This depends on valve size, type, pressure drop across the valve, and media. A 1-inch ball valve in water at 5 bar might need only 20 Nm, while a 4-inch butterfly valve at 10 bar could need 200+ Nm. When in doubt, specify higher torque — a larger actuator is always safer and allows for aging, corrosion or increased resistance over time.
Do you need simple on/off operation, or modulating (proportional) control? On/off is simpler and cheaper but allows only two positions. Modulating control is essential for applications requiring flow regulation, temperature control or gradual opening/closing. Most modulating applications need a 4-20mA control signal compatible with your BMS or control system.
Specify an IP rating appropriate to the environment: IP65 for dry indoor locations, IP67 for outdoor or splashing environments, IP68 for permanently wet or submersed installations. If your application is in a hazardous area (explosive gas, vapour or dust atmosphere), you must specify ATEX-certified actuators meeting the appropriate Zone rating.
In critical applications such as fire suppression, emergency shutoff or safety systems, specify failsafe mechanisms. Spring-return actuators automatically return to a safe position (open or closed) if power is lost. Battery backup actuators allow emergency manual operation even if mains power fails.
Check your available power supply: single-phase AC (110V or 230V), three-phase (380V, 400V or 415V), or DC (24V). Most modern actuators offer multi-voltage options, but confirm compatibility with your electrical infrastructure before ordering.
Electric actuators offer numerous advantages over manual operation and alternative automation technologies. Unlike pneumatic actuators, electric units require only an electrical connection — no compressed air supply or pipework needed. This makes them cheaper to install, easier to maintain and more reliable in remote locations. Electric actuators also provide superior control precision, making them ideal for modulating applications and BMS integration. Many modern electric actuators are smart-enabled, offering advanced diagnostics, remote operation and integration with industrial IoT platforms.
Modern electric actuators from leading manufacturers deliver exceptional reliability with MTBF (mean time between failures) ratings exceeding 100,000 operating hours. The shift from brush motors to brushless DC technology has eliminated regular brush replacement and dramatically extended service intervals. With proper installation and maintenance, an electric actuator will reliably operate for 10+ years in demanding industrial applications.
While the initial cost of an electric actuator may be higher than a pneumatic equivalent, the total cost of ownership is typically lower due to reduced power consumption, minimal maintenance requirements and longer service life. Electric actuators also reduce installation costs by eliminating the need for compressed air infrastructure. For modulating applications, electric actuators pay for themselves quickly through improved energy efficiency and process control.
Today's electric actuators are designed for easy integration with modern control systems. Standard 4-20mA analogue signals ensure compatibility with any BMS, PLC or SCADA system. Many units offer Modbus, Profibus or MQTT connectivity for direct industrial network integration. Position feedback, temperature monitoring, and diagnostic functions allow predictive maintenance and reduce downtime.
Reputable electric actuator manufacturers comply with international standards including ISO 5210 (multi-turn), ISO 5211 (part-turn), and IEC 60730 for safety. ATEX certification is essential for hazardous area applications. Always confirm compliance with relevant standards before specifying actuators for critical or regulated applications.