UNI-T UTP3305-II DC Power Supply, 3 Channel, 30V, 5A, 335W, Linear

Uni-T UTP3305-II DC Power Supply

The UTP3305-II is an upgraded, precision-focused version of UNI-T's popular UTP3305 power supply, maintaining the same 335 W, three-channel linear design while enhancing performance and usability. A four-digit LED display provides readings with 10 mV and 1 mA resolution, complemented by improved regulation specifications and a temperature-controlled cooling system for quieter, more efficient operation. Two independently adjustable outputs supply 0 to 32 V at up to 5 A each, while a dedicated third channel delivers a fixed 5 V at 3 A for powering logic circuits and digital electronics. Straightforward controls, standard banana terminals, and built-in overvoltage and overcurrent protection make it easy to use without a steep learning curve.

Its linear regulation architecture keeps output ripple below 1 mVrms, eliminating switching noise and EMI that can interfere with sensitive testing and characterization work. Channels 1 and 2 can be linked in series to provide up to 64 V or connected in parallel for up to 10 A of output current. Enhanced load regulation, rated at CV < 0.01% + 3 mV, helps maintain stable output even during rapid load changes, ensuring dependable power delivery for demanding laboratory, engineering, and development applications.

• Three Outputs, 335 W Total Capacity – CH1 and CH2 provide adjustable outputs from 0 to 32 V at up to 5 A each, while CH3 supplies a fixed 5 V, 3 A output ideal for digital and logic circuits.
• High-Visibility Four-Digit LED Metering – Dedicated voltage and current displays for each channel offer precise monitoring with 10 mV voltage and 1 mA current resolution.
• Improved Regulation Performance – Delivers excellent stability with load regulation of CV <0.01% + 3 mV and CC <0.2% + 3 mA, plus tracking accuracy of ±(0.1% of reading + 30 mV).
• Linear Power Design with Ultra-Low Noise – Produces clean, stable DC output with ripple and noise levels of ≤1 mVrms, eliminating switching-related interference and harmonics.
• Automatic CV/CC Mode Switching – Seamlessly transitions between constant-voltage and constant-current operation as load conditions change, while providing built-in current-limit protection.
• Flexible Series and Parallel Operation – Link CH1 and CH2 in series for outputs up to 64 V or in parallel for currents up to 10 A, selectable directly from the front panel.
• Smart Temperature-Regulated Cooling – An intelligent cooling fan adjusts speed according to internal temperature, reducing noise during light use while maintaining effective thermal management under heavy loads.
• Convenient Output Enable Control – A front-panel output switch allows users to activate or disable power delivery instantly without changing output settings.
• Straightforward Front-Panel Interface – Traditional knobs and push-button controls provide reliable, intuitive operation with no software, firmware updates, or network configuration required.

What's in the Box

• Uni-T UTP3305-II DC Power Supply
• Power cord conforming to the destination country
• Test output line
• English user manual

FAQ Uni-T UTP3305-II DC Power Supply

Does the UTP3305-II have USB or SCPI?

No. The UTP3305-II is a traditional, non-programmable linear DC power supply designed for standalone bench operation. It does not include USB or LAN interfaces, SCPI command support, or PC control software. Users who require remote automation or integration with test systems should consider UNI‑T's programmable models, such as the UDP3303C and UDP3305C, which offer USB and RS-232 connectivity, or the UDP3000S Series, which adds USB, LAN, LXI compatibility, and browser-based control.

What's the difference between the UTP3305 and UTP3305-II?

The UTP3305-II is an updated precision version of UNI‑T's established 335 W, three-channel linear power supply platform. The most notable improvements are increased display resolution and measurement precision, with voltage and current readouts improving from 100 mV/10 mA to 10 mV/1 mA. Each channel also benefits from a four-digit display instead of a three-digit display. In addition, the UTP3305-II incorporates a temperature-regulated cooling fan and published programming accuracy specifications. Core characteristics such as output power, channel configuration, ripple performance, and overall functionality remain largely unchanged. Users seeking finer measurement visibility and quieter cooling performance will generally prefer the UTP3305-II, while the original UTP3305 may remain attractive for cost-sensitive applications.

Why a linear supply instead of switching?

A linear power supply is often preferred in precision testing and development environments because it delivers exceptionally clean DC output with minimal noise. Unlike switching designs, it does not generate high-frequency switching artifacts or related harmonic emissions, and output ripple remains below 1 mVrms. This can be particularly beneficial when working with sensitive analog circuits, audio electronics, low-noise sensors, and measurement systems where power-supply noise can influence results. The primary compromise is lower efficiency and greater heat generation compared to switching supplies, but for many bench-top laboratory applications, these trade-offs are outweighed by the superior output quality and measurement confidence.