Overview

The UNI-T UTL1020S is a single-channel programmable DC electronic load rated 200 W, 0–150 V, 0–30 A. It runs four constant modes — CC, CV, CR, CP — plus eleven additional test modes including dynamic, OVP, OCP, time, CR-LED, battery, automatic list, short-circuit, load-effect, combination, and list, for 15 test modes in total. Synchronous sampling reaches 500 kHz with high-performance DSP processing and a self-adaptive voltage and current waveform display on the 4.3-inch TFT LCD.

Dynamic mode pulls load at up to 50 kHz so current and voltage peaks — Vpp and Ipp — can be observed directly. The load also provides on-screen ripple measurement, a rear-panel Sense terminal for remote voltage compensation, and SCPI remote control over RS232 with a HANDLER interface and USB Host port for data logging and automated production test.

Choosing Your Model — 200 W 15-Mode Load

Two 200 W models share the same load architecture, the same 15 test modes, the same accuracy class, and the same 0–150 V / 0–30 A input envelope. They differ in one axis only: measurement resolution.

This page describes the UTL1020S. Capability, test modes, protection, and interfaces below apply to both 200 W models; the Specifications table lists this model's resolution figures.

Key Features

UNI-T UTL1020S Details

15 Test Modes for Power, Battery, and LED-Driver Validation

Four constant modes — CC (constant current), CV (constant voltage), CR (constant resistance), CP (constant power) — plus eleven more: dynamic, OVP, time, OCP, CR-LED, battery, automatic list, short-circuit, load effect, combination, and list. The CR-LED mode simulates real LED forward-voltage behavior for LED-driver testing; battery mode records charge and discharge curves; combination mode pairs two basic modes (CR+CC, CV+CR, CV+CC) for more realistic DUT conditions.

Dynamic Mode — 50 kHz Transient Load Simulation

Dynamic mode pulls load at frequencies up to 50 kHz with T1/T2 timing from 10 µs to 50 s (1 µs resolution) and a programmable rising/falling current slope of 0.0006 A/µs to 3 A/µs. The current and voltage peak waveforms are observed directly on screen with Vpp and Ipp measurement, so transient response and overshoot of the device under test can be characterized without a separate oscilloscope.

Battery Test with Charge and Discharge Curves

Battery mode performs constant-current or constant-power discharge testing and records the full discharge curve. The UTL1020S captures both the discharge and the charging curve, so capacity, internal-resistance behavior, and cycle characteristics are traceable from a single instrument — useful for battery-pack, BMS, and power-bank validation.

Automatic List Test — 200-Step Programmable Sequences

The automatic list test runs editable multi-step, multi-mode sequences with up to 200 steps. Set the appropriate load value and mode for each step and the list executes the full test process automatically. List files save to internal memory or a USB drive and can be imported, so a validated production-test sequence transfers between units quickly.

On-Screen Ripple Measurement and Real-Time Waveform

Ripple is measured and displayed directly in the corner of the screen, replacing a separate oscilloscope measurement for routine power-supply ripple checks. Pressing the [WAVE] function key shows the live voltage and current waveform, with the self-adaptive display scaling automatically to the signal.

OVP and OCP Protection Testing

Set the protection threshold according to the device under test and the UTL1020S measures the protection function and the protection response time. Overvoltage protection triggers with delayed protection at ≥ 152 V and immediate protection at ≥ 165 V; overcurrent protection at ≥ 30.3 A delayed and ≥ 33 A immediate; overpower at ≥ 202 W delayed and ≥ 220 W immediate. Instrument protection can also be turned off to prevent false alarms during characterization.

Load Effect Test

The load effect test automatically measures and calculates load-regulation results from the configured test values, so power-supply load regulation is characterized without manual point-by-point measurement and calculation.

Time Test — Rise and Fall Time of the Power Supply

Time test measures the rise and fall times of the device under test against configured thresholds, with 1 µs timing resolution and ±100 ppm timing accuracy, for power-supply turn-on / turn-off and transient-timing characterization.

Applications

The 200 W 15-mode envelope — CC/CV/CR/CP plus dynamic, battery, list, protection, load-effect, and combination modes with 500 kHz sampling — covers R&D and production test for power electronics.

• Switching power-supply and adapter test — load regulation, ripple, transient response, and protection-function verification from one instrument.
• Battery and battery-pack characterization — charge and discharge curve recording for capacity, BMS, and cycle testing.
• LED-driver validation — CR-LED mode simulates real LED forward-voltage behavior.
• Charger and power-bank testing — automatic list sequences for repeatable multi-step production test.
• DC-DC converter and module test — dynamic loading at up to 50 kHz to characterize transient overshoot and recovery.
• Automated production test (ATE) — SCPI over RS232 plus HANDLER interface for test-line integration; list import/export for fast line setup.

Accessories and Family Options

Included with Every Unit

• AC power cord
• RS232 communication cable
• Plug-in terminal block (5.08-2P) and screw-free spring terminal block (2.54-6P)
• Spare fuse (2 pcs)
• Certificate of calibration and multi-language safety precautions

Optional Test Leads

• UT-L0615-OO — double O-type terminal, 60 A / 1.5 m
• UT-L0320-UU — double U-type terminal, 30 A / 2 m
• UT-L0312-UU — double U-type terminal, 30 A / 1.2 m
• UT-L0110-BB — double fold-insert, 10 A / 1 m
• UT-L0110-BU — fold-insert to U-type, 10 A / 1 m

UTL1000S Series

Four models share the same chassis, 15 test modes, 500 kHz sampling, accuracy class, and 0–150 V / 0–30 A input envelope:

• UTL1020S — 200 W, high-resolution (this product)
• UTL1020S-E — 200 W, standard resolution
• UTL1040S — 400 W, high-resolution
• UTL1040S-E — 400 W, standard resolution

Frequently Asked Questions

Warranty

This instrument is backed by UNI-T's 3+2 Year Warranty — 3 years of standard coverage, plus 2 additional years free when you register your product. That's 5 years of total protection at no extra cost.

The warranty covers manufacturing defects and component failures under normal use conditions. UNI-T instruments are built for professional daily use, and our warranty reflects that commitment to long-term reliability.