1. Sarrera
The DROK LD25 USB Load Tester is an intelligent temperature-controlled electronic load module designed for testing USB and Type-C power sources and cables. It features high power, high current, and high voltage capabilities, along with intelligent control for precise measurements. This device is ideal for verifying charger output capacity, testing cable quality, and performing bulk aging tests.
It provides a constant current discharge task up to 4A, 25V, and 25W, offering a user-friendly interface and robust performance for diverse testing requirements.
2. Segurtasun informazio garrantzitsua
OHARRA: This product does not have reverse connection protection. The input polarity cannot be reversed. Reversing the input polarity will cause permanent damage to the product and it cannot be repaired. Always ensure correct polarity before connecting the device.
Ziurtatu eragiketa bolumenatage, current, and power do not exceed the rated maximums to prevent damage to the device or the power source being tested.
3. Produktuaren ezaugarriak eta osagaiak


- 4-Digit LED Digital Display: Ikuskizunak voltage, current, and power values.
- Hozte-haizagailu adimenduna: Oil bearing fan with intelligent temperature control, speed up to 5800±10% RPM. Activates automatically when current exceeds 2A or temperature exceeds 40°C.
- Precision Adjustable Potentiometer: Allows fine-tuning of the output current.
- USB Male Port: For connecting to USB power sources.
- Micro USB Port (Max. Current: 2A): For testing Micro USB cables and devices.
- Type-C Port (Max. Current: 4A): For testing Type-C cables and devices.
- ON/OFF tekla: Short press to toggle the load output on or off. Long press to set the default boot state (output on or off) for future use.
- Ezarri tekla: Short press to cycle through the display modes: Voltage (V), Current (A), and Power (W). Long press to enter the protection setting menu.
- Full Aluminum Heat Sink: Efficient heat dissipation for stable operation.
- Babes-ezaugarriak: Bolumen gehiegitage protection (OVP), Over-power protection (OPP), Over-temperature protection (OTP).
4. Zehaztapenak

| Parametroa | Balioa |
|---|---|
| Baloratu operatiboa Boltage | DC 4-25.0V |
| Gehienezko deskarga-potentzia | 25W |
| Funtzionamendu-korronte nominatua | 0.25-4.00A (Min. 0.05A when fan is off) |
| Fan Abiadura | Oil bearing intelligent temperature control fan, 5800±10% RPM |
| Constant Current Resolution | ± (% 1 + 3 digitu) |
| Beroa xahutzeko metodoa | Intelligent temperature control fan + Aluminum heat sink |
| Laneko Tenperatura | -10 ℃ ~ + 40 ℃ |
| Potentiometro erregulagarria | Precision multiloop adjustable potentiometer |
| Bistaratzeko modua | 4-bit LED tube |
| Zabalkuntza Portuak | Micro USB port, Type-C port |
| Produktuaren neurriak | 84 x 41 x 28 mm |
| Produktuaren pisua | 57 g |

5. Konfigurazioa
- Prepare Power Source: Ensure the power source (e.g., USB charger, power bank) you intend to test is within the operating voltagDC 4-25.0V-ko tentsio-tartea.
- Connect the Load Tester:
- For standard USB power sources: Plug the USB male port of the LD25 directly into the USB output port of your charger or power bank.
- For Micro USB or Type-C cables/devices: Connect the Micro USB or Type-C port of the LD25 to the respective cable or device.
- Egiaztatu konexioa: Once connected, the 4-digit LED display should illuminate, indicating the device is powered on. If it does not power on, check the connection and ensure the power source is active.
- Initial Current Setting: Before applying a load, ensure the adjustable potentiometer is set to a low current or off position to avoid sudden high current draw.
6. Funtzionamendu-argibideak
6.1 Oinarrizko funtzionamendua
- Piztu/Itzali:
- Sakatu laburra ON / OFF tekla to toggle the load output on or off.
- Luze sakatu ON / OFF tekla to set the default boot state (output on or off) for future use.
- Korrontea doitzea: Biratu Potentiometro erregulagarria to increase or decrease the discharge current. The current value will be displayed on the LED screen. Adjust gradually to the desired load.
- Bistaratzeko moduak: Sakatu laburra Ezarri tekla to cycle through the display modes: Voltage (V), Korrontea (A) eta Potentzia (W).
- Setting Protection Modes: Luze sakatu Ezarri tekla to enter the protection setting menu. Refer to Section 7 for details on protection functions.
6.2 Intelligent Cooling Fan Operation
The intelligent cooling fan will automatically activate under the following conditions to maintain optimal operating temperature:
- When the discharge current exceeds 2A.
- When the internal temperature of the device exceeds 40°C.
The fan supports continuous 25W discharge and ensures uninterrupted operation by efficiently dissipating heat.

7. Protection Functions and Troubleshooting
The LD25 USB Load Tester incorporates several protection mechanisms to ensure safe operation and prevent damage to the device and connected equipment.
- OVP (Boltage Babesa):
- Activates if the input voltage exceeds 25V (up to 30V).
- The digital display will show "OVP".
- Kontuz: liburukiatages exceeding 30V can cause permanent damage.
- OTP (Over-Temperature Protection):
- Activates if the load temperature exceeds 80°C.
- The device will stop working, and the digital display will show "OTP".
- OPP (Over-Power Protection):
- Activates if the discharge power exceeds 25W.
- The device will stop working, and the digital display will show "OPP".
When a protection condition is met, the device will halt operation. To resume, address the underlying issue (e.g., reduce voltage, allow cooling, reduce power draw) and then manually or automatically reset the load as configured.
8. Aplikazioak
The DROK LD25 USB Load Tester is a versatile tool for various testing scenarios:
- Charger Testing: Measure the actual output current capacity of USB chargers and power banks.
- Kablearen Kalitatearen Probak: Evaluate the quality and performance of Micro USB and Type-C charging cables by observing voltage drop under load.
- Bulk Aging Tests: Suitable for factory quality control and aging tests of chargers and power supplies.
- Power Delivery Verification: Confirm stable power output from various USB power sources.

9. Mantentzea
To ensure the longevity and accurate performance of your DROK LD25 USB Load Tester:
- Garbiketa: Erabili zapi leun eta lehor bat gailua garbitzeko. Ez erabili garbitzaile likidorik edo disolbatzailerik.
- Biltegiratzea: Gorde gailua leku fresko eta lehor batean, eguzki-argitik eta muturreko tenperaturetatik babestuta.
- Manipulazioa: Saihestu gailua kolpe gogorrak erortzea edo jasaten.
- Aireztapena: Ensure the cooling fan and heat sink are free from dust and obstructions to maintain efficient heat dissipation.