Linear actuator wiring confuses a lot of people — not because it's complicated, but because there are several different  wiring methods depending on what you want the actuator to do. This guide covers all of them: basic ON/OFF switch  control, relay wiring, PWM speed control, and microcontroller integration. You'll understand exactly which method suits  your project.

Before You Start: Understand How a Linear Actuator Works  Electrically

A DC linear actuator is essentially a DC motor driving a lead screw through a gearbox. Like any DC motor, it:

• Runs in one direction when positive voltage is applied (extends the rod)
• Runs in the reverse direction when polarity is reversed (retracts the rod)
• Stops when power is removed (and self-locks in position via the lead screw)
• Has a built-in limit switch at both ends of travel — when the rod fully extends or retracts, the internal limit switch cuts motor power automatically

This last point is important: you cannot damage the actuator by holding the switch past the end of stroke. The internal limit switch handles this. However, you can damage it by applying the wrong voltage, exceeding the current rating, or running it without adequate rest time (duty cycle).

Actuator Terminals

Almost all 12V/24V DC linear actuators have two power wires — typically red (+) and black (−), or sometimes both black.

To reverse direction: swap the + and − connections (reverse polarity). That's the fundamental principle behind every wiring method below.

Method 1: SPDT Rocker/Toggle Switch (Simplest)

Best for: Simple manual control with one switch, basic DIY projects, furniture applications

An SPDT (Single Pole Double Throw) switch has 3 terminals: COM (common), NO (normally open), and NC (normally closed). With two SPDT switches wired as an H-bridge, you can control direction.

However, the easiest approach is a dedicated DPDT (Double Pole Double Throw) switch or a rocker switch rated for  actuator use. This is a pre-made H-bridge in switch form.

DPDT Switch Wiring Diagram

12V Power Supply (+) ──────────────────────────── (+) Rail

12V Power Supply (−) ──────────────────────────── (−) Rail

DPDT Switch:

      Pin 1 (top-left) → (+) Rail

      Pin 2 (top-right) → (+) Rail

      Pin 3 (center-left) → Actuator Wire A (red)

      Pin 4 (center-right) → Actuator Wire B (black)

      Pin 5 (bottom-left) → (−) Rail

      Pin 6 (bottom-right) → (−) Rail

      Position UP → Actuator extends

      Position DOWN → Actuator retracts

      Position MID → Actuator stops (if switch has center-off)

Parts needed:

• DPDT rocker or toggle switch rated for your actuator's stall current (e.g., 10A at 12V for most standard actuators)
• 12V DC power supply (or battery) with adequate current capacity
• Appropriate wire gauge (see wire sizing table below)

Note: Always check the switch's current rating against your actuator's stall current — not its running current. A typical  standard actuator draws 2–5A running but may draw 8–15A at stall. Undersized switches fail quickly.

Method 2: Relay Wiring (Remote Control or High-Current  Applications)

Best for: Applications where the switch is far from the actuator, high-current actuators (>10A), 12V automotive/marine installations, systems controlled by a remote or timer

A relay acts as an electrically operated switch — a small control signal (from a button, timer, or controller) switches a high-current circuit.

For bidirectional actuator control, use two SPDT relays wired as an H-bridge, or a single DPDT relay.

Two-Relay H-Bridge Wiring

RELAY 1 (Extend)                                                                                        RELAY 2 (Retract)

─────────────────────────────────────────────────────

Coil (+) → Extend Button → 12V+                                                       Coil (+) → Retract Button → 12V+

Coil (−) → GND                                                                                        Coil (−) → GND

Relay 1 COM → 12V+                                                                                 Relay 2 COM → GND

Relay 1 NO → Actuator Wire A                                                                Relay 2 NO → Actuator Wire A

Relay 1 NC → (not connected)                                                                 Relay 2 NC → (not connected)

Actuator Wire B → GND (via Relay 2 when energized, reverses polarity)

Simplified explanation:

• Press Extend button → Relay 1 energizes → (+) goes to Wire A → actuator extends
• Press Retract button → Relay 2 energizes → polarity reverses → actuator retracts
• Release button → relay de-energizes → actuator stops

Parts needed:

• 2× SPDT relays rated for actuator stall current + 30% safety margin (e.g., 20A relay for a 15A stall actuator)
• Flyback diodes across relay coils (to protect the control circuit from voltage spikes)
• 2-button momentary switch panel

Wiring for Remote Control (12V RF Remote)

Most 12V RF relay modules (available online) include a built-in H-bridge relay circuit. Simply:

1.Connect 12V power to the relay module's VCC and GND

2.Connect the actuator's two wires to the relay module's motor output terminals

3.Pair the RF remote per the module instructions

This is the fastest way to add wireless control to any JDR actuator.

Method 3: PWM Speed Controller

Best for: Applications where actuator speed needs to be adjustable — conveyor positioning, solar trackers with fine adjustment, medical equipment

A PWM (Pulse Width Modulation) controller varies the effective voltage to the actuator motor by rapidly switching power on and off. Higher PWM duty cycle = higher effective voltage = faster speed.

Important: PWM control works well with brush DC motors (standard in most linear actuators). It does not affect the self-locking behavior — the actuator still holds position when stopped.

PWM Wiring (with H-bridge PWM module)

12V Supply (+) → PWM Module VCC

12V Supply (−) → PWM Module GND

PWM Module OUT1 → Actuator Wire A

PWM Module OUT2 → Actuator Wire B

Speed control: turn the potentiometer or use a digital input to set duty cycle

Direction control: use the DIR pin or H-bridge direction input

Recommended modules: IBT-2 (BTS7960 H-bridge, up to 43A), L298N (up to 2A — only for mini actuators), Cytron MD10C (10A)

Method 4: Arduino / Microcontroller Control

Best for: Automated systems, position-controlled applications with feedback sensors, integration into larger control systems

Basic Arduino + L298N Wiring (for mini actuators up to 2A)

// Pin definitions

const int IN1 = 8;        // L298N IN1

const int IN2 = 9;       // L298N IN2

const int ENA = 10;    // PWM pin for speed

void setup() {

pinMode(IN1, OUTPUT);

pinMode(IN2, OUTPUT);

pinMode(ENA, OUTPUT);

}

void extend() {

digitalWrite(IN1, HIGH);

digitalWrite(IN2, LOW);

analogWrite(ENA, 255); // Full speed

}

void retract() {

digitalWrite(IN1, LOW);

digitalWrite(IN2, HIGH);

analogWrite(ENA, 255);

}

void stopActuator() {

digitalWrite(IN1, LOW);

digitalWrite(IN2, LOW);

}

Position Control with Hall Effect Feedback

JDR actuators with Hall feedback output pulse signals proportional to motor rotation. Use an Arduino interrupt pin to

count pulses and calculate position:

volatile long pulseCount = 0;

void countPulse() {

pulseCount++;

}

void setup() {

attachInterrupt(digitalPinToInterrupt(2), countPulse, RISING);

}

// Move to target position (in pulses)

void moveToPosition(long targetPulse) {

if (pulseCount < targetPulse) {

extend();

while (pulseCount < targetPulse) {} // Wait for target

} else {

retract();

while (pulseCount > targetPulse) {}

}

stopActuator();

}

Note: This is a simplified example. For production use, implement proper PID control and software end-stop limits.

Wire Gauge Selection

Using the wrong wire gauge causes voltage drop (slower actuator, overheating) or fire risk. Use this table:

Always fuse the circuit at the power supply end. Use a fuse rated at 125–150% of the actuator's maximum running current. For a 5A running current actuator, use a 7.5A fuse.

Common Wiring Mistakes (and How to Avoid Them)

Mistake 1: Powering from a USB or Arduino Pin Directly

Arduino output pins supply 40mA maximum — enough for an LED, not even close to a linear actuator (typically 2–15A). Always use a dedicated motor driver/H-bridge between the microcontroller and the actuator.

Mistake 2: Reversing Polarity Without a Proper H-Bridge

Connecting the actuator directly to a simple ON/OFF relay (not DPDT or H-bridge) and expecting to control direction doesn't work. You need polarity reversal — which requires an H-bridge or DPDT relay configuration.

Mistake 3: Undersized Power Supply

Many hobbyist projects use a phone charger or light-duty adapter. A 12V/1A power supply cannot run most linear actuators — they draw 2–10A running, with stall currents 2–3× higher. Use a proper power supply rated for at least 2× the actuator's running current.

Mistake 4: No Flyback Diode on Relay Coils

When a relay coil is de-energized, it generates a voltage spike (back-EMF) that can damage microcontrollers or cause erratic behavior. Always place a 1N4007 diode (or similar) across each relay coil, oriented in the reverse direction.

Mistake 5: Ignoring Duty Cycle

Running the actuator continuously or cycling it faster than its duty cycle rating will cause overheating. For the wiring to work reliably long-term, the control logic must enforce rest periods between operations. See our duty cycle guide for details.

Wiring for Specific JDR Actuator Series

Frequently Asked Questions

Q: My actuator only moves in one direction — what's wrong?

A: The most common cause is a wiring error in the DPDT switch or relay H-bridge. Check that the polarity is actually reversing between the two switch positions. Use a multimeter on DC voltage mode at the actuator terminals — one direction should show positive voltage, the other should show negative voltage (polarity reversed).

Q: Can I wire two actuators to move in sync?

A: Yes — connect them in parallel to the same power supply and switch. Both actuators will receive the same voltage and move simultaneously. However, minor speed differences between units can cause mechanical stress if the actuators share a rigid frame. For precision synchronization, use two separate motor controllers with position feedback — see our Hall effect feedback guide for details.

Q: What happens if I connect a 12V actuator to 24V?

A: The actuator will run faster (approximately double speed) but draws significantly more current and generates much more heat. This drastically reduces motor life and will void any warranty. Always match supply voltage to the actuator's rated voltage. JDR industrial actuators are available in 12V, 24V, and 48V versions — specify the correct voltage at ordering.

Q: Can I use a dimmer switch to control actuator speed?

A: No. Household dimmer switches are designed for AC lighting loads and are incompatible with DC motors. They will

damage the actuator motor. Use a dedicated DC PWM speed controller instead.

Summary: Choosing the Right Wiring Method

For actuator selection advice, use our Engineering Force Calculator or browse our full product range: Standard Actuators | Mini Actuators | Industrial Actuators. Need a custom wiring solution for a specific application? Contact our engineering  team.