UNI-T UDP3303C-U Linear DC Power Supply User Manual

Preface

Thank you for purchasing the new linear DC power supply. In order to use this product safely and correctly, please read this manual thoroughly, especially the Safety Information part. After reading this manual, it is recommended to keep the manual at an easily accessible place, preferably close to the device, for future reference.

Limited Warranty and Liability

Uni-Trend guarantees that the product is free from any defect in material and workmanship within 3 years from the purchase date. This warranty does not apply to damages caused by accident, negligence, misuse, modification, contamination or improper handling. The dealer shall not be entitled to give any other warranty on behalf of Uni-Trend. If you need warranty service within the warranty period, please contact your seller directly.

Uni-Trend will not be responsible for any special, indirect, incidental or subsequent damage or loss caused by using this device.

Safety Information

Important safety instructions must be followed for operating and storing the UDP3303C-U series. To ensure your personal safety, read the following instructions carefully before operation to ensure that the UDP3303C-U series is in the best working environment.

Safety Symbols

• ⚠️ Warning or Caution
• ⚡ Caution, possibility of electric shock
• ? Earth (ground) TERMINAL

Safety Guidelines

General Introduction

• Do not block and isolate the air inlet and vent.
• Avoid physical impact or using the instrument improperly.
• Do not discharge static electricity onto the instrument.
• Only professionals should open the instrument.

AC Input

• AC input voltage: 110V/120V/220V/230V, 50/60Hz.
• Connect the protective ground wire to the earth to avoid shock hazard.

Fuse

• Make sure to use the correct fuse type before starting up.
• To prevent fires, only replace with fuses that meet the model and rating value.
• Do not connect the power before replacing the fuse to avoid electric shock.
• Confirm the cause of the blown fuse before replacing it.

Power Supply

AC input voltage includes 100V/120V/220V/230V ±10%, 50/60Hz. You can select different input voltages through the "AC SELECTOR" on the rear panel as needed. Please disconnect the power before switching the input voltage.

UDP3303C-U Linear DC Power Supply Introduction

The UDP3303C-U DC power supply has three independent outputs: two are adjustable outputs of 30V/3A, and the third is a fixed selectable output of 1.8V/2.5V/3.3V/5V/3A (fine adjustable). The device also features constant voltage (CV) and constant current (CC) modes, short circuit, and overvoltage protection.

UDP3303C-U Main Features

• 4-digit voltage and current high precision display.
• Overvoltage and overcurrent protection.
• Output voltage/current settings viewable.
• Remote control (output ON/OFF).
• USB-Device communication interface (for software upgrade and upper computer control of power output).
• RS232 interface.
• 5 sets of setup storage: M1-M5.
• Shutdown memory.
• Buttons lock.
• Intelligent temperature-controlled fan.
• USB phone charging interface.

Device Overview

Front Panel

The front panel features an LCD display, store buttons (M1-M5), channel buttons (CH1, CH2), output on/off, buzzer control, OVP/OCP buttons, voltage and current adjustment knobs, and CH3 output controls. It also includes outputs for CH1, CH2, CH3, Ground, PARA OUT, and SER OUT, along with a mobile phone charging USB interface.

Diagram Description: The front panel of the UDP3303C-U is shown with labels pointing to the LCD display, various buttons (SET VIEW, M1-M5, CH1, CH2, SER/INDEP, PAR/INDEP, OUTPUT, OVP, OCP, LOCK), adjustment knobs for voltage and current, and the three output channels (CH1, CH2, CH3) with their respective terminals and indicators.

Rear Panel

The rear panel includes a USB communication interface, a remote control port, an RS232 communication interface, an AC selector for input voltage, a power ventilation hole, and a power input port. Safety certifications (TUV, CE, UKCA) are also visible.

Diagram Description: The rear panel of the UDP3303C-U is depicted, highlighting the USB communication interface, RS232 communication interface, remote control port, AC selector, and power input. A warning about disconnecting the power cord before replacing the fuse is also present in English and French.

Main Index Parameters

Test conditions: Turn on the device for 30 minutes at temperature +20°C~+30°C.

CH1/CH2 Parameters

CH3 Parameters

USB (CH4) Parameters

Note: Limited by the output terminal structure, the voltage load adjustment rate is not guaranteed.

Function Introduction

1. Voltage / Current Setting and Output

• Voltage setting: Press the CH1 button. The cursor will flash on the CH1 voltage position. Use the voltage knob to move the cursor and adjust the voltage value.
• Current setting: Press CH1 again. The cursor will flash on the CH1 current position. Use the current knob to move the cursor and adjust the current value.
• Press CH2 to set the CH2 voltage and current values using the same method.
• Press the OUTPUT button to enable CH1, CH2, and CH3 outputs after setting voltage and current.
• The device features a shutdown memory function, restoring the last set value upon restart.

The operation and display interfaces are described in accompanying diagrams.

2. Series and Parallel Settings

2.1 Series Settings

• Press the CH1 button for 3 seconds to enter series mode (the "SER" symbol will appear). CH1+ serves as the main positive output, and CH2- as the slave negative output. Series voltage and current settings are adjusted via CH1, with CH2 settings following CH1.
• The total series voltage is twice the CH1 voltage, and the total current equals CH1 current.
• To exit series mode, long-press the CH1 button for 3 seconds until the "SER" symbol disappears.
• The shutdown memory function restores last settings and series mode upon restart.

Diagram Description: An illustration shows the series output connection, indicating the positive and negative outputs for CH1 and CH2.

2.2 Parallel Settings

• Press the CH2 button for 3 seconds to enter parallel mode (the "PARA" symbol will appear). CH1+ is the main positive output, and CH1- is the slave negative output. Parallel voltage and current settings are adjusted via CH1, with CH2 settings following CH1.
• The parallel voltage equals the CH1 voltage, and the total current is twice the CH1 current.
• To exit parallel mode, long-press the CH2 button for 3 seconds until the "PARA" symbol disappears.
• The shutdown memory function restores last settings and parallel mode upon restart.

Diagram Description: An illustration shows the parallel output connection, indicating the positive and negative outputs for CH1.

3. Constant Voltage / Constant Current

In constant voltage (CV) mode, the channel indicator is green. The voltage remains at the set value. If the output current reaches the set value, the device switches to constant current (CC) mode.

In constant current (CC) mode, the channel indicator is red. The output current matches the set value, and the voltage is lower than the set value. If the output current drops below the set value, the device switches back to constant voltage mode.

Diagram Description: An illustration shows the channel indicators, likely indicating the CV/CC status for each output channel.

4. OVP (Overvoltage Protection), OCP (Overcurrent Protection) Setting and Enabling

• OVP Setting: Long-press the OVP button (>3s) to enter OVP threshold setting. Press CH1 or CH2 to select the channel, then use the voltage knob to set the OVP limit. Long-press OVP again to exit.
• OVP Enabling: Short-press the OVP button (backlight on) to enable protection. If output voltage exceeds the limit, output shuts off, and the OVP symbol disappears. Short-press again (backlight off) to disable.
• OCP Setting: Long-press the OCP button (>3s) to enter OCP threshold setting. Press CH1 or CH2 to select the channel, then use the current knob to set the OCP limit. Long-press OCP again to exit.
• OCP Enabling: Short-press the OCP button (backlight on) to enable protection. If output current exceeds the limit, output shuts off, and the OCP symbol disappears. Short-press again (backlight off) to disable.

5. Remote Control DIGITAL I/O Interface

To remotely control the output and shutoff of CH1/CH2, short-circuit or disconnect pins 1 and 2 of the DIGITAL I/O terminal using a wire or relay.

• When pins 1 and 2 are short-circuited, the front panel OUTPUT button is disabled, power output is forcibly turned on, and the "ON" symbol appears on the LCD.
• When the short circuit is released, the OUTPUT button function is restored, and power output turns off, showing the "OFF" symbol on the LCD.

Diagram Description: An image shows the DIGITAL I/O port, illustrating how to remotely control power output by shorting or releasing PIN 1 and 2.

6. CH3 Output

The CH3 offers 4 sets of fixed outputs: 1.8V, 2.5V, 3.3V, and 5.0V at 3A, adjustable via the OUTPUT button. Pressing the CH3 button cycles through these voltages, with the corresponding indicator lighting up. Double-pressing the CH3 button allows fine adjustment of the CH3 voltage.

The device has a shutdown memory function, restoring the last set value upon startup.

Diagram Description: Illustrations show the CH3 operation and display interfaces, including CH3 scale indicators, CH3 scale selection, CH3 CV/CC indicator, and CH3 output terminal. The LCD displays the selected voltage scale.

7. M1-M5 Store/Recall Functions Introduction

After setting output parameters, long-press one of the M1-M5 buttons (>3s) to save the configuration. Short-press an M1-M5 button to recall the stored data, indicated by the button's backlight turning on.

Diagram Description: An image displays the front panel of the UDP3303C-U, highlighting the M1-M5 store buttons.

8. USB Interfaces

• USB Host (Front Panel): This interface is not for communication but serves as an independent CH4 channel with a fixed output of 5V/2A, suitable for charging mobile phones.
• USB Device (Rear Panel): This interface provides communication functions for software programming, upgrades, and controlling the power supply via a computer.

Diagram Description: An image shows the USB Host interface on the front panel, labeled as a mobile phone charging USB interface. Another image shows the USB communication interface on the rear panel.

9. RS232 Interface

The RS232 interface on the rear panel offers communication capabilities for software programming, upgrades, and controlling the power supply from a computer.

Diagram Description: An image shows the RS232 communication interface connector.

10. OTP (Over-temperature Protection) Overview

The power supply contains two thermistors on the heat sink. If the heat sink temperature reaches approximately 100°C, the over-temperature protection is triggered. The output will shut off, and the "OTP" symbol will flash on the LCD screen, accompanied by periodical beeps. The "OTP" symbol disappears when any key is pressed.

11. SET VIEW Introduction

When the power output is active, the LCD displays real-time sampled output voltage and current values. Pressing the SET VIEW button (backlight on) allows viewing the set voltage and current values. Pressing it again (backlight off) returns the LCD to displaying real-time output values.

12. Buzzer On and Off

Press the BEEP button (backlight on) to enable the buzzer. Long-press the BEEP button for 3 seconds to disable it.

The shutdown memory function ensures that the last saved settings are restored upon device startup.

When the buzzer is enabled, it beeps for events such as:

• Power on/off
• CH1/CH2 setting switching
• Independent - series – parallel switching
• Output on/off
• OVP/OCP setup and on/off
• Pressing the voltage/current knob
• SET VIEW (setting/output) display switching
• LOCK/UNLOCK operation
• Panel lock/unlock
• CH3 output selection

13. Buttons Lock

• Short-press the LOCK button: The button backlight turns on, and the panel buttons are locked.
• Long-press the LOCK button (>3s): The button light turns off, and the panel buttons are unlocked.

Limited Warranty and Liability

UNI-T guarantees the Instrument product is free from any defect in material and workmanship within three years from the purchase date. This warranty does not apply to damages caused by accident, negligence, misuse, modification, contamination, or improper handling. If warranty service is needed within the warranty period, please contact your seller directly. UNI-T is not responsible for any special, indirect, incidental, or subsequent damage or loss caused by using this device. For probes and accessories, the warranty period is one year. Visit instrument.uni-trend.com for full warranty information.

Learn more at: www.uni-trend.com

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UNI-T is the licensed trademark of UNI-TREND TECHNOLOGY (CHINA) CO., Ltd. UNI-T products are protected by patent laws in China and internationally. Licensed software products are the properties of UNI-Trend and its subsidiaries or suppliers. All rights reserved. This manual supersedes all earlier published versions. Product information is subject to update without notice. For more information on UNI-T Test & Measure Instrument products, applications, or service, please contact UNI-T instrument support. The support center is available at www.uni-trend.com > instruments.uni-trend.com.

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Contact Information

Headquarter

UNI-TREND TECHNOLOGY (CHINA) CO., Ltd.
Address: No.6, Industrial North 1st Road, Songshan Lake Park, Dongguan City, Guangdong Province, China
Tel: (86-769) 8572 3888

Europe

UNI-TREND TECHNOLOGY EU GmbH
Address: Affinger Str. 12
86167 Augsburg Germany
Tel: +49 (0)821 8879980

North America

UNI-TREND TECHNOLOGY US INC.
Address: 3171 Mercer Ave STE 104, Bellingham, WA 98225
Tel: +1-888-668-8648

Manufacturing Specifications

The following details are related to the manual's production and are primarily in Chinese:

Model: UDP3303C-U

Part NO.: 110401113457X

Manufacturer: UNI-TREND TECHNOLOGY (CHINA) CO., LTD.