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This $30 USB-C meter will tell you if your iPhone chargers are genuine or not

The ChargerLab Power-Z C240 is a handy accessory that provides key charging diagnostics.
Written by Adrian Kingsley-Hughes, Senior Contributing Editor
ChargerLab Power-Z C240 in action!

ChargerLab Power-Z C240 in action!

Adrian Kingsley-Hughes/ZDNET

ZDNET's key takeaways

  • The ChargerLab Power-Z C240 power meter is available for $30.
  • There are no buttons or dials to learn to use, and its plug-and-play functionality couldn't be easier to use.
  • The display is a little on the small side, and there are no advanced features.

USB testers are incredibly handy tools. These small dongles plug inline with a cable to evaluate USB ports and the outputs from chargers, offering valuable insight into a device's functionality (or lack thereof).

I frequently use them for various purposes, such as verifying if a charger or cable is functional, checking if a device is charging, monitoring how much power a device draws, and even determining the total power capacity of a battery.

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Given their utility, I always keep a handful of these testers on hand. Maybe that's why I'm often asked, "What's a good, affordable, easy-to-use USB tester?" 

My top recommendation is the ChargerLab Power-Z C240. It's an excellent choice for those new to using these tools or anyone looking for a reliable tester without breaking the bank.

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ChargerLab Power-Z C240 tech specs

  • Display: 1.14-inch color IPS 135 x 240 pixel display
  • Ports: USB-C (USB-A supported with converter)
  • Max Power: 240W
  • Voltage: 0 - 50V
  • Current: 0 - 6A
  • Other Features: D+, D-, CC voltages, Wh reading, runtime timer
  • Bidirectional: Yes 
ChargerLab Power-Z C240 features

ChargerLab Power-Z C240 features


Many USB testers can be quite cumbersome, overloaded with buttons and dials that make them complex to use. A good example is the FNIRSI FNB58 -- a feature-rich meter that unfortunately comes with a steep learning curve.

In contrast, the Power-Z C240 is refreshingly straightforward. You simply plug it in, and it starts up immediately, displaying all the necessary data on its color screen.

Although the display is on the smaller side, it is sharp, bright, and colorful, making the information easy to read and understand. This user-friendly design makes the C240 an excellent choice for those who need a functional USB tester without the complexity.

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A pro tip to consider: If you find the screen hard to read, use your phone to take a photo or video of it. 

This meter also supports up to 240W of power transfer, which means it's future-proofed as faster chargers continue to hit the market.

ZDNET's buying advice

At $30, the ChargerLab Power-Z C240 is an excellent value, offering robust capabilities without a hefty price tag. It's a smart choice for anyone looking to keep up with the latest in charging technology while ensuring future compatibility with high-powered devices.

If you're looking for a more professional-grade USB tester that can display graphs, identify charging protocols, and perform ripple and cable resistance tests, then the Power-Z KM003C might be the ideal choice for you. This meter is designed to provide deeper insights and comprehensive testing capabilities, making it perfect for users who require higher precision data for diagnostics and evaluation.  

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