4000W Variable Voltage Speed Controller LED Display | 110V–220V

4000W Stepless Motor Speed Controller with LED Display

Take precise control of your power tools and appliances with this heavy-duty 4000W Variable Voltage Speed Regulator. Designed for workshops, job sites, and home use, this compact controller lets you fine-tune the speed, temperature, and voltage of compatible devices — all at the turn of a precision knob. The bright LED display shows real-time output voltage at 1-volt accuracy, so you always know exactly where you stand.

Key Features

• Wide Compatibility: Works with exhaust fans, tungsten filament bulbs, electric furnaces, angle grinders, marble cutters, blowers, and more. Not suitable for devices with circuit boards or capacitive components (e.g. microwave ovens, induction cookers, rice cookers, water pumps, washing machines, LED energy-saving lights).
• High-Quality ABS Shell: Flame-retardant, heat-resistant ABS plastic housing resists discolouration, warping, and cracking. Internal components use thickened phosphor bronze for enhanced safety and long service life.
• High-Precision LED Display: Precision pressure-regulating knob delivers voltage control accuracy down to 1 volt, with a clear LED screen for real-time monitoring.
• Overload & Short-Circuit Protection: Built-in independent switch automatically cuts power when instantaneous current exceeds 15A, safeguarding both the controller and connected devices. Status indicator light confirms operating state at a glance.
• 3-Gear Stepless Variable Speed Knob:
  • 🟢 Green — Low (0–40%)
  • 🟡 Yellow — Mid (41–70%)
  • 🔴 Red — High (71–99.9%)
• Convenient Back Hook: Integrated hanging hook lets you attach the unit to a tool bag or belt loop for hands-free portability — plug and play.

Specifications

⚠️ Important Notice: Maximum rated power is 4000W; resistive load must stay within 2000W and inductive load within ~1000W. Only motors that support voltage-reduction and speed regulation are compatible. Do not exceed these limits.

What's in the Box

• 1 × Voltage Speed Regulator Controller

Related Products You May Like

• 25-in-1 Precision Magnetic Screwdriver Set | Pro Repair Kit
• 34-Compartment Double-Sided Hardware Storage Box & Dividers
• 5-in-1 Diamond Knife Sharpener | Kitchen & Scissor Sharpener

Learn more: OSHA guidance on hand and power tools

Frequently Asked Questions

Q: What types of devices can I use with this 4000W variable voltage speed controller?

A: This speed controller is compatible with resistive and simple inductive loads such as exhaust fans, angle grinders, electric drills, marble machines, blowers, electric furnaces, and tungsten filament bulbs. It is not compatible with devices that have circuit boards or capacitive components — including microwave ovens, induction cookers, rice cookers, water pumps, washing machines, and LED energy-saving lights.

Q: What does the LED display show, and how accurate is the voltage control?

A: The built-in LED display shows the real-time output voltage of the connected device. The precision regulating knob allows voltage adjustment with an accuracy of 1 volt, giving you fine, reliable control over your tool's operating speed or power level.

Q: Does the speed controller have any safety protection features?

A: Yes. The unit is equipped with overload and short-circuit protection. If the instantaneous current exceeds 15 amperes, the controller automatically cuts power to protect both itself and any connected equipment. An indicator light lets you monitor the operating status at all times.

Q: Is this controller compatible with both 110V and 220V power supplies?

A: Yes. The input voltage range is AC 110V–250V, making it suitable for use with both North American (110V) and international (220V) power supplies. The output is fully adjustable from 0V up to the input voltage level.