USB tester electro base UT658 — voltage and current measurement for USB devices

The electro base UT658 is a compact USB tester engineered for inline measurement of voltage and current on USB connections. Designed to be placed between a USB power source and a connected device, the UT658 provides real-time numeric readings that help verify chargers, power banks and USB cables. The device assists technicians and end users in diagnosing charging problems, confirming power delivery parameters and ensuring safe, compatible charging conditions for smartphones, tablets and other USB-powered gadgets.

Advantages

The UT658 delivers clear, continuous readings of voltage and current without interrupting normal charging. Its compact form factor makes it easy to insert into a USB cable path and transport between test points. The tester operates with common USB power sources and devices, allowing quick verification of output voltage stability and charging current under load. Readouts support troubleshooting of weak cables, faulty chargers and unexpected power draw, enabling faster identification of issues.

Suitable for

• Testing USB chargers and wall adapters
• Verifying power bank output and capacity behavior under load
• Diagnosing charging problems with smartphones, tablets and accessories
• Checking USB cable quality and voltage drop over a connection
• Verifying USB power delivery in field service and repair workflows

Key specifications

• Measurement parameters: DC voltage and DC current
• Connection type: inline USB connection for power in and power out
• Display: real-time numeric readout for voltage and current
• Form factor: compact, portable inline tester suitable for bench and field use
• Compatibility: works with standard USB-powered devices and chargers

How to use

Insert the UT658 inline between the USB power source and the device under test by connecting the power source to the tester input and the device to the tester output. Power on the source and observe the display for instantaneous voltage and current values while the device is charging or under load. Compare measured values to the expected output of the charger or device specifications to identify deviations, unstable voltage, or excessive current draw. Remove the tester once measurements are complete and disconnect safely.

Usage recommendations

Use the tester with cables and connectors in good condition to avoid misleading voltage drop readings. When measuring, allow the device under test to reach a steady charging state for accurate current readings. Avoid exposing the tester to moisture and high temperatures; store it in a dry environment when not in use.