ADCA AVM/AVF234S electric actuator

ADCA high-efficiency electric actuator: AVM/AVF234S

In industrial automation and HVAC systems, the accuracy, reliability, and energy efficiency of valve actuators directly affect the control quality of the entire system. The AVM234S and AVF234S series linear electric actuators are ideal choices in the fields of steam humidification, drain valve control, and process regulation due to their automatic stroke adaptation, high protection level, compatibility with multiple control signals, and fail safe functions. This article will provide a comprehensive and in-depth technical interpretation of the series of actuators from the dimensions of product design, core features, technical parameters, control modes, optional accessories, electrical connections, mechanical dimensions, and typical applications.

Product positioning and design background

AVM234S and AVF234S are electric actuators designed specifically for valve linear drive, particularly suitable for TDS (Total Dissolved Solids) control systems consisting of DSH series direct steam injection humidifiers and VCP drain valves. The main difference between the two is that the AVF234S has a spring reset function, which drives the actuator to the preset fail safe position (push rod extension) in the event of power failure or interruption, while the AVM234S does not have a spring reset function.

Both actuators support automatic detection of valve travel, achieving high-precision activation, while also having extremely low operating noise and high energy efficiency. Its IP66 protection level enables it to operate stably in humid and dusty environments.

Summary of Main Characteristics

IP66 protection level: completely dust-proof, can withstand strong water spray, suitable for harsh industrial environments.

Automatic detection of control signals: The control signal type (0... 10 V, 4... 20 mA, 2-point or 3-point step control) is automatically identified through LED indicator lights.

Adjustable characteristic curve: Linear, quadratic, or equal percentage characteristics can be selected through DIP switches to adapt to different valve flow characteristics.

Automatic travel adaptation: The actuator can automatically detect and adapt to the actual travel of the valve without manually setting limits.

Manual operation: The motor gearbox can be detached and operated with a manual wrench for easy debugging and emergency situations.

Mechanical travel indicator: an externally visible mechanical indicator that displays valve opening in real-time.

Spring reset (AVF234S only): After power failure, the spring drives the push rod to extend, achieving fault safe closing or opening (depending on the installation direction).

Multiple control inputs: Supports 2-point control, 3-point step control, analog 0... 10 V or 4... 20 mA.

Optional accessories: Split range adjustment unit, auxiliary contacts, potentiometer, high temperature adapter, etc.

In depth analysis of technical specifications

1. Power supply and power consumption

AVM234S and AVF234S support multiple power versions:

230 V 50/60 Hz

110 V 50/60 Hz

24 V 50/60 Hz

24 V DC

In terms of power consumption:

24V version: 10 W (20 VA)

230 V version: 13 W (28 VA)

When designing, it is necessary to configure a transformer with sufficient capacity according to the selected voltage, otherwise it may cause actuator failure.

2. Running time and itinerary

The motor operating speed can be configured to select three gears:

10 mm/min（0.17 mm/s）

15 mm/min（0.25 mm/s）

30 mm/min（0.50 mm/s）

Spring reset time (AVF234S only): 15 to 30 seconds (within the range of travel 14... 40 mm), regardless of the set motor running time.

Actuator travel:

AVM234S：0…49 mm

AVF234S：0…40 mm

drive:

AVM234S：2.5 kN

AVF234S：2.0 kN

Spring reset life: greater than 40000 times.

3. Positioner and control parameters

Control signal 0... 10 V: Input impedance 100 k Ω

Control signal 4... 20 mA: Input impedance 50 Ω

Position feedback 0... 10 V: load>2.5 k Ω

Starting point (U ₀): can be set to 0 V or 10 V

Control range (Δ U): 10 V

Switch range (Xsh): 300 mV

These parameters enable the actuator to interface directly with the vast majority of PLCs, DDCs, or process controllers without the need for additional signal conditioning.

4. Environmental conditions

Working temperature: -10 ℃ to+55 ℃

Medium temperature (conducted through valves): up to 130 ℃ (if using a high-temperature adapter, it can reach 180 ℃ or 200 ℃)

Environmental humidity:<95% RH, no condensation

Protection level: IP66 (EN 60529)

Protection level: III (IEC 60730)

EMC Directive: 2014/30/EU, compliant with EN 61000-6-2 (immunity) and EN 61000-6-4 (emission)

Low Voltage Directive: 2014/35/EU, compliant with EN 60730-1 and EN 60730-2-14

Overvoltage category: III

Pollution level: III

Control mode and automatic detection

The actuator supports multiple control modes, automatically recognized through DIP switch selection and LED indication:

2-point control: switch signal (on/off), suitable for simple switch valve applications.

3-point step control: Two switch signals (on/off/off) can achieve precise position control, and can be optionally paired with a potentiometer.

Analog control: 0... 10 V or 4... 20 mA, continuously adjustable, suitable for regulating valves.

When the control signal is connected, the actuator automatically detects the signal type and lights up the corresponding LED. Automatic travel adaptation function: After the first power on or reset, the actuator will slowly move to the fully closed and fully open positions of the valve, record the travel endpoint, and automatically calculate the appropriate limit and force threshold. This process does not require manual intervention and greatly simplifies debugging.

Spring Reset Function (AVF234S) Detailed Explanation

AVF234S is equipped with a built-in spring mechanism, which drives the push rod to move against the spring force during normal power supply; Once the power is cut off or the control signal is lost, the spring energy storage is released and the push rod is pushed to the extended position (i.e. the fail safe position). This position usually corresponds to the valve being closed (for normally closed valves) or open (for normally open valves), depending on the installation method.

The spring reset time varies with the load and stroke, with a typical value of 15-30 seconds. The spring design has a lifespan of over 40000 complete reset cycles, meeting the requirements of the entire lifecycle of industrial equipment.

Adjustable characteristic curve

Through DIP switches, users can choose three types of valve core characteristic curves:

Linear: The valve opening is proportional to the flow rate and is suitable for general liquids or gases.

Secondary: parabolic shape, suitable for certain HVAC applications.

Equal percentage: The flow gain increases with the increase of opening, suitable for systems with pressure loss changes, such as steam or wide modulation ratio applications.

This feature allows the actuator to perfectly match different valve bodies without the need to replace the actuator or use external characterization modules.

Accessories and Function Expansion

AVM234S/AVF234S offers a wide range of optional accessories to meet complex control requirements:

Accessory model and function description

313529 001 Split range adjustment unit (independent junction box), used for sequence control, such as two actuators split range adjustment in the same circuit

372332 001 2/3 o'clock and analog activation module, 230 V AC ± 15%, additional power consumption of 2 VA

372332 002 Same as above, 100 V AC ± 15%

372333 001 auxiliary conversion contact (12... 250 V AC), variable, minimum 100 mA, load 6 (2) A

372333 002 gold-plated auxiliary contact, suitable for small signals from 1 mA to 30 V, load 3 (1) A

372334 001 potentiometer 2 k Ω/1 W/24 V, used for 3-point step closed-loop control

372334 002 potentiometer 130 Ω/1 W/24 V

372334 006 Potentiometer 1 k Ω/1 W/24 V

372336 180 high temperature adapter (medium temperature 130... 180 ℃)

372336 240 high temperature adapter (medium temperature 180... 240 ℃)

These accessories significantly expand the application range of actuators, from simple on-off valves to high-precision regulation, split range control, remote position feedback, and extreme temperature conditions.

Electrical Connection and Wiring Guide

The document provides a detailed wiring diagram (omitting the image description, but the text explanation is as follows):

For the 2-point/3-point step control with a 230 V AC power module (372332 001), the wiring includes power L/N, control signals (Y1/Y2), and common terminals.

The wiring of the 100 V AC module (372332 002) is the same.

Auxiliary contacts, potentiometers, high-temperature adapters, and split range units must be connected according to the corresponding terminals.

Important precautions:

Transformers that meet the power requirements of the actuator must be used, otherwise it may cause difficulty or malfunction in starting the motor.

The control signal line should use shielded cables and be wired separately from the power line to avoid electromagnetic interference.

The spring reset model should ensure that the power is disconnected before wiring to prevent mechanical damage caused by accidental reset.

Mechanical dimensions and installation

The external dimensions of the actuator (unit: mm) are shown in the following table:

Model A B C D E F G H I M Weight (kg)

AVM234S 230 314 90 72 40 57 18 37 18 M10 4.1

AVF234S 230 314 90 72 40 57 18 37 18 M10 4.1

Installation precautions:

The actuator should be installed above the valve body, with the push rod aligned with the valve stem to avoid lateral forces.

Adapter (372336 180 or 240) must be used under high-temperature medium conditions to isolate heat conduction and protect the internal electronic components of the actuator.

IP66 protection requires all cable entrances to use suitable waterproof connectors, and unused interfaces to be sealed with plugs.

Manual operating mechanism: After power failure, the motor gear can be disengaged using a wrench or specialized tool to manually rotate the drive shaft.

Typical application scenarios

Steam humidification system: In conjunction with the DSH series direct steam jet humidifier, it precisely controls the steam volume and maintains constant humidity.

Boiler discharge control: Installed on the VCP discharge valve, it controls the conductivity of boiler water by periodically or continuously discharging according to TDS measurement values.

HVAC water system: used for two-way or three-way regulating valves to control the flow of cold or hot water.

Process fluid regulation: Proportional regulation of various liquids and gases in chemical and pharmaceutical plants.

Fault safety scenario: Select AVF234S and automatically place the valve in a safe position when power is cut off (such as closing toxic gas pipelines or opening cooling water bypass).

Selection Guide and Precautions

When choosing AVM234S or AVF234S, the following factors should be considered:

Do you need spring reset: If the valve is required to return to the predetermined safe position after power failure, select AVF234S; Otherwise, choose AVM234S to reduce costs and achieve slightly larger travel (49mm vs 40mm) and slightly higher thrust (2.5kN vs 2.0kN).

Power supply voltage: Power supplies available on site (230V, 110V, 24V AC/DC), please note that the 24V DC version can also be used for 24V AC, but ripple needs to be confirmed.

Control signal: PLC output type (analog or switch), whether position feedback is required.

Medium temperature: If it exceeds 130 ℃, a high-temperature adapter should be selected; If the temperature exceeds 180 ℃, a 240 ℃ adapter must be selected.

Environmental temperature: Ensure it is within the range of -10~55 ℃, otherwise special heating or cooling measures are required.

Travel requirements: Measure the valve travel, with a maximum of 49mm for AVM234S and 40mm for AVF234S. If it exceeds the range, the model needs to be changed.

Operating speed: Select 10/15/30 mm/min according to the system response requirements.

Summary of Installation and Debugging Steps

Mechanical installation: Fix the actuator onto the valve body through brackets and couplings to ensure concentricity.

Electrical wiring: Connect according to the wiring diagram based on the selected control mode and power supply. The grounding terminal must be reliably grounded.

Pre power on inspection: Confirm that the power supply voltage is consistent with the actuator nameplate; Manually operate the disengagement mechanism and check if the valve operates smoothly.

Automatic travel adaptation: After the power is turned on, the actuator will automatically perform a full travel adaptation (indicator light flashes) without manual intervention. If you need to re adapt, you can press the reset button or power off and restart.

Characteristic curve selection: Set linear, quadratic, or equal percentage through DIP switch.

Run test: Provide 0%, 50%, and 100% control signals and observe whether the valve position and feedback signal correspond. For 3-point step control, test the on/off function.

Manual operation verification: After power off, disconnect the motor and manually rotate the drive shaft to confirm that the valve can be fully opened and closed.

Maintenance and troubleshooting

Regular inspection: Every 6 months, check whether the cable joints are loose, whether the protection level is maintained, and whether the push rod seal is leaking.

Spring reset test (AVF234S): Cut off the power and confirm that the actuator can return to the fault safe position within the specified time. If it exceeds the time limit or gets stuck, it may cause spring fatigue or increased mechanical resistance.

Common faults and possible causes:

The actuator does not operate: no power supply, control signal error, motor thermal protection triggered, manual disconnection not reset.

Inaccurate travel: incomplete automatic adaptation, valve jamming, loose coupling.

Abnormal position feedback: worn potentiometer (if used), disconnected wiring.

LED indication abnormality: Control signal type mismatch or signal out of range.

Repair: Internal electronic modules and motor components are usually repaired by the manufacturer, and only fuses (if any) can be replaced or external wiring checked on site.

Compliant standards and certifications

The AVM234S/AVF234S series actuators are produced in accordance with the reasonable engineering practices of the European Pressure Equipment Directive (PED) and comply with:

EN 60529（IP66）

IEC 60730 (Automatic Electrical Control)

EN 61000-6-2 / -6-4（EMC）

EN 60730-1/-2-14 (low voltage)