DC Power Supply Variable 120V 3A Adjustable - Compact Bench Unit

In this review the DC Power Supply Variable 120V 3A Adjustable is evaluated as a compact bench supply aimed at hobbyists, small labs and repair work. The single biggest reason to consider it is the combination of an intelligent charging mode with safety detection that stops charging when a battery is full, which simplifies charging tasks and reduces risk. The unit's small footprint and an 18W USB output make it practical for bench use where space and a secondary device charger matter.

Key Features

• Intelligent charging mode: Real-time display of charging power (Ah) and automatic stop when a battery is fully charged prevents overcharging and simplifies battery maintenance.
• Overcurrent detection alarm: The OCP button enables a protective alarm and stops output on short circuits or overcurrent, protecting connected equipment.
• Compact footprint: At under 2.3 lb and roughly 7.59 x 3.35 x 6.1 in, the supply fits tight bench spaces used in labs, classrooms or home workstations.
• 18W USB interface: A built-in 18W USB port provides convenient faster charging for phones or accessories without occupying the main output terminals.
• Multi-layer safety protections: Grounding, leakage, thermal and overload safeguards help ensure reliable operation and extended component life.
• Precision encoder knob: The adjustment knob allows fine control of voltage output for tasks that need accurate settings, though coarse feel may vary by user.

Who It's For

This unit suits small laboratories, electronics hobbyists, repair technicians and schools that need an affordable, space-saving DC supply with intelligent battery charging and multiple protections. Its USB port and compact size make it useful for makers and bench techs who also charge devices while working.

Those who require high continuous power, full laboratory-grade bench features, or extremely fine mechanical coarse adjustment may prefer a larger or more premium regulated supply; the encoder knob provides precise fine adjustments but some users report the coarse adjustment feel is less smooth.

Pros & Cons

Pros

• Intelligent charging with Ah readout and auto-stop reduces risk of overcharging batteries.
• Built-in overcurrent detection alarm and several safety protections make it reliable for repeated bench use.
• Very compact and lightweight, making it easy to place on crowded benches or transport between workspaces.
• 18W USB output is useful for charging mobile devices without using the main terminals.

Cons

• Some users find the coarse adjustment on the encoder knob less intuitive, requiring time to get used to for large voltage changes.
• Not intended for high-power continuous loads where a larger rated supply would be needed.

Specifications

Maximum voltage	120V
Maximum current	3A
USB output	18W
Weight	Under 2.3 lb
Dimensions	7.59 x 3.35 x 6.1 in
Protection features	Grounding, leakage, thermal, voltage overload, power overload, short-circuit
Included	Output power cords, input power cord, user manual

Our Verdict

The DC Power Supply Variable 120V 3A Adjustable is a solid value for bench users who prioritize compact size, safety features and a convenient 18W USB port. It is particularly good for hobbyists, classrooms and small repair tasks where intelligent charging and multiple protections matter; those needing heavier continuous power should choose a larger supply.

Frequently Asked Questions

Does it stop charging when a battery is full?
Yes. The intelligent charging mode monitors Ah and stops charging automatically when the battery reaches full charge.

Can it protect against short circuits?
Yes. The OCP overcurrent detection alarm stops output and sounds an alert when a short circuit or overcurrent is detected.

Is the unit portable for field use?
Yes. At under 2.3 lb and compact dimensions it is easy to move between benches or take to classrooms and small work sites.