Inside every electric height adjustable desk, a motor spins a lead screw that lifts the surface. Most linear actuators in lifting columns use either brushed DC motors or brushless DC motors (BLDC). The choice affects efficiency, noise, control finesse, and lifespan. If you are sourcing a standing desk for home or deploying a fleet for offices and labs, understanding the trade-offs helps you buy smarter and support the gear longer.

What actually changes inside the actuator

• Brushed DC: Carbon brushes deliver current to the spinning commutator. It is a simple, low-cost design with wide availability and familiar control electronics. Wear parts are the brushes and commutator.

• Brushless DC (BLDC): Electronics handle commutation with position feedback from Hall sensors or sensorless estimation. No brushes to wear, higher efficiency, and better torque control at low speed.

Both motor types can power a stable, ergonomic standing desk when paired with a well-built lifting column and a smart control box. But their behavior over years of daily lifts is not the same.

Noise and smoothness you can hear

• Startup and low-speed “cogging”: BLDC motors excel at smooth microsteps when control firmware is dialed in, reducing cogging at low speeds. That translates into quieter motion and fewer “jerks” that can excite wobble in long monitor arms.

• Tonal noise: Brushed motors can produce a distinct whine or brush chatter at certain speeds, especially as brushes age. High-quality geartrains and lubrication mitigate this, but the signature tends to grow over time.

• Damping at height: A quiet drive helps a height adjustable desk feel calmer at full extension. BLDC systems, with better torque control, usually keep noise in the mid-40s dB(A) at the user’s ear more consistently across load and stroke.

Efficiency, heat, and duty cycle

• Electrical efficiency: BLDC motors typically convert more input power to useful torque, shedding less as heat. Over fleets, lower power draw during motion and cooler operation add up.

• Heat under repetition: In classrooms, labs, or hot-desking zones where desks move dozens of times a day, BLDC’s higher efficiency and thermal margins reduce thermal cutoffs and early slowdowns.

• Standby draw is separate: Standby power depends on the control box design, not the motor choice. Aim for less than 0.5 watt standby regardless of motor type to keep energy use down.

Lifespan and maintenance

• Wear parts: Brushed motors have consumable brushes. Life depends on duty cycle and load, but brushes eventually wear and can introduce electrical noise. BLDC removes that wear point.

• Bearings and gears still matter: Regardless of motor type, hardened gears, proper lubrication, and quality bearings inside the linear actuator drive daily feel and longevity.

• Field service: In most standing desk systems, you replace the entire lifting column assembly when the actuator fails. BLDC can push that replacement farther into the future, especially in heavy-use environments.

Control finesse: ramps, sync, and anti-collision

• Soft start/stop: Both motor types benefit from firmware ramps in the control box. BLDC’s torque control makes it easier to implement gentler, more consistent ramps that prevent end-of-travel thumps.

• Synchronization: A dual-motor desk depends on accurate leg sync to avoid racking. With Hall sensors in each motor, BLDC systems can deliver tighter closed-loop control across a wide load range, which you feel as fewer micro-corrections.

• Anti-collision sensitivity: Current-based detection and IMU-assisted systems both work with brushed or BLDC motors. BLDC’s smoother current signature can reduce false positives when cable management is clean, but routing and slack loops still make the biggest difference.

Cost and value by use case

• Brushed advantage: For single-user home offices with light desktops and modest daily moves, a well-made brushed system delivers great value. You get a quiet, stable standing desk at a lower entry price.

• BLDC advantage: For shared stations, tall users with heavy tops, and open offices that notice tonal noise, BLDC offers quieter motion, better low-speed control, and longer life. Over three to five years, fewer service calls and a more refined feel often repay the premium.

• Mixed fleets: Many programs standardize on BLDC for high-traffic zones (benching, classrooms, pods) and use brushed systems for private offices or conference side tables.

What does not change with motor type

• Structure rules stability: Long, gusseted feet, a rigid crossbar, and precise three-stage lifting columns determine wobble at height. Motor choice cannot fix a flimsy frame or a thin, hollow-core top.

• Cable management prevents “mechanical” issues: A rear cable tray, mounted power strip, and a single vertical cable chain with slack loops eliminate most snags and rattles that users interpret as motor problems.

• Controller ergonomics drive adoption: A readable desk controller with three or four memory presets sets the habit. Users will not use an app-only desk if the physical buttons are awkward or hidden.

Specs to ask for in RFQs

• Motor type and commutation: Brushed DC or BLDC with Hall sensors; note if the control box supports both.

• Noise method: dB(A) measured at user ear height, under defined load, at multiple heights (25%, 50%, 90% stroke).

• Speed under load: Rated lift speed (mm/s) with a realistic dynamic load, not unloaded.

• Duty cycle and thermal behavior: Allowed continuous run time and cool-down period; any automatic derate behavior under heat.

• Control features: Soft start/stop ramps, anti-collision up and down, leg synchronization method, child lock, error codes, and a straightforward reset procedure.

• Power: 100–240 V, 50/60 Hz control box with less than 0.5 W standby; region-specific certified cord sets.

• Structure: Three-stage lifting columns, reinforced crossbar, long feet, and grade-marked fasteners—motor choice cannot compensate for weak structure.

Choosing for your environment

• Quiet open offices: Favor BLDC linear actuators, three-stage columns, and a dense 25–30 mm top. Keep monitor arm clamps close to a lifting column.

• Budget home setups: A brushed system on a stable frame with good cable management and a readable controller is the best value. Add a keyboard tray for shorter users if the minimum height is a concern.

• Education and lab benches: BLDC helps with repeated moves and low noise during instruction. Pair with sealed control boxes if wipes and solvents are common.

• Conference and AV tables: Multi-leg synchronization, smooth ramps, and mid-40s dB(A) are priorities; BLDC typically hits those targets with margin.

Installation and service tips

• Square and torque: Loosely assemble, square the frame, then torque crossbar and feet in a star pattern. A racked frame creaks no matter the motor.

• Reset and test: After install, run a full down reset on the desk controller, set presets, and perform foam-block anti-collision tests up and down.

• Cable discipline: Tie down bricks inside the tray, separate AC and low-voltage, and route one power drop via a vertical cable chain. Many “motor” tickets end as cable fixes.

• Spares plan: For fleets, stock one control box, one desk controller, and one lifting column per 50 desks. “Swap, don’t debug” brings stations back online fast.

Both brushed and brushless actuators can power a quiet, stable height adjustable desk when the frame, columns, and control box are well engineered. If you want the most refined motion, lower noise across loads, and a longer maintenance interval, BLDC earns its premium—especially in shared, high-visibility spaces. If budget is tight and usage is light, a quality brushed system on a solid frame remains a smart choice. In every case, structure and cable management determine daily satisfaction more than motor type alone.

• Explore linear actuators, lifting columns, and height adjustable desk frames—brushed and brushless options—at Venace: https://www.vvenace.com

• Contact us: tech@venace.com