USB Tester Current Voltage Capacity Meter 4-20V 0-3A Timer KWS-V20 Blue USB Meter Portable PnP for Battery Charger Power Bank

High-concerned chemical : none Type : Module Origin : Mainland China Condition : New

USB Power Meter! KWS-V20 Current Voltage Capacity Tester – 4-20V, 0-3A, Timer 0-99H, ±1% Accuracy. Test Chargers, Power Banks, Cables – Plug and Play! Key Features & Benefits Multi-Function Measurement: Real-time display of voltage (4-20V), current (0-3A), capacity (mAh), energy (Wh), time (0-99H).

Battery Capacity Test: Test power banks, phone batteries – check health and real capacity.

Charger Performance Test: Check USB chargers (phone chargers, car chargers, computer USB ports) for output quality.

Cable Loss Evaluation: Compare input vs output voltage – identify poor quality cables.

Plug and Play: No external power needed – simply insert into USB circuit.

Wide Applications: Factory testing, lab use, DIY projects – test chargers, power banks, USB device power consumption. Product Description Want to know if your charger is underperforming? The real capacity of your power bank? Cable loss? This KWS-V20 USB voltage current capacity tester is the tool you need. Blue transparent housing, compact size – just insert into the USB charging circuit to monitor voltage, current, capacity, energy, and time in real time. Voltage range 4-20V, current 0-3A, ±1% accuracy, timer up to 99 hours. Perfect for testing phone chargers, measuring power bank capacity, or evaluating cable loss. Plug and play, no external power needed. Essential for factory QC, lab testing, and DIY projects. Quick Start Guide & Important Tips What It Does & What You Need This tester does:

Measures USB voltage (4-20V) and current (0-3A)

Accumulates capacity (mAh) and energy (Wh)

Timer function (0-99 hours)

Tests chargers, power banks, cables This tester does NOT: Support >20V or >3A, trigger fast charging protocols, waterproof You will need: Device to test (charger, power bank, cable, USB load), USB power source Package includes:

1-Pack: KWS-V20 Tester ×1

3-Pack: Testers ×3 Usage in 3 Steps 1️⃣ Connect Tester: Plug the tester's USB-A male end into the charger or power bank (input). Connect the device under test to the tester's USB-A female port (output).

2️⃣ Power On: The display lights up showing voltage and current. Short press the button to cycle through readings (voltage/current/capacity/energy/time).

3️⃣ Read Data:

Voltage (V): 4-20V range – 5V charger should show 4.8-5.2V

Current (A): Depends on load – max 3A

Capacity (mAh): Accumulated charge – for battery testing

Energy (Wh): Accumulated energy

Time (H): Elapsed time since power-on (max 99H) ️ Critical Warnings: Voltage/Current Limits: Do not exceed 20V or 3A – may damage tester.

Polarity: Tester is directional – USB-A male = input, female = output. Do not reverse.

Accuracy: ±1% – suitable for general testing. For higher precision, use professional equipment.

Fast Charging Protocols: This tester does not trigger fast charging – it only measures actual voltage/current. Use a protocol trigger for fast charging testing. Button Functions Short Press Cycle display: Voltage → Current → Capacity → Energy → Time Long Press Reset capacity, energy, and time to zero Common Questions Tester not working or display abnormal?

Check input power source (charger/power bank has power)

Ensure secure USB connections

Try a different power source or cable

How to test power bank capacity? Fully charge the power bank. Connect tester (input from power bank, output to USB load like resistor or phone). Discharge power bank until auto-shutdown – read capacity (mAh) on tester. Use constant current load for accurate results.

Current shows 0.00A?

Ensure a load is connected to output

Load may be very low power (<10mA) – below tester resolution

Check if load is working

Can it test fast charging? It can measure actual voltage/current during fast charging, but cannot trigger fast charging protocols. Use a fast charging charger and device, or a protocol trigger.

How to reset data? Long press the button for about 3 seconds – capacity, energy, and time will reset to zero. Note: Due to manual measurement, please allow 1-3mm error. Color may vary slightly due to monitor differences. Please refer to the actual product.

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