PortaPow USB Power Blocker - Stops Charging, Allows Data (Single Pack)

Perfect for what I needed it for! I have a Heltec LoRa board connected to a Raspberry Pi but the Pi is unable to deliver the Heltec's needed power supply. With this, I'm able to maintain the serial connection while putting the Heltec on battery power. This thing works very well!

They work as intended, I'm using one with a Raspberry Pi (running Octopi) attached to an Ender 3 v2 printer to enable controlling the printer via Wi-Fi. Apparently you can damage your Raspberry Pi if you allow the Ender 3 v2 USB port to back feed power into it. This adapter severs the power lines while still allowing the two devices to communicate properly. It's far more elegant then modifying a USB cable. Devices wouldn't communicate at first but it was a bad cable not this adapter so make sure your USB cable is good. They're great value for the money, they can also be used to help eliminate USB power noise on some digital audio interfaces like the Scarlet series for example.

USB Power Blocker works exactly as described. Many people sell Data Blockers, it's hard to find a Power Blocker. this works great... solves the problem with a poorly designed USB Port causing voltage issues.

Does exactly what I wanted it to do. I wanted to use it, to automatically turn on/off a 2.5" mechanical hdd I use for backup. I used a portable enclosure with a 4 tb 2.5mm mechanical drive with a usb-c Y adapter with one USB to connect to a computer and another is plugged into a tasmota usb power switch, which can be controlled by hardware. This way I am able to "unplug" and "plug" the hard drive into the computer using a python script, all 100% automated.

From other reviews, I suppose this product works fine for USB 1 or 2 based devices, but it does not support USB 3+, effectively lowering transfer speeds down to USB 2 480Mbs). So if you're trying to connect a powered hub and avoid backfeeding the power to your host (like a Raspberry Pi), you will be stuck with slow transfer speeds. I only put one star because of other reviews and product build quality seems acceptable.

Does exactly what it says is does. Prevents 5v power from reaching the device. Really only needed when dealing with self-powered devices that don't implement USB properly, which either try to backpower the host, or partially start only the 5v components. In the past I'd carve up a cable, and cut the 5v line, or modify the target device itself, and this is a bit easier of a solution. Things work well at 12Mbps (USB 1 "Full" speed). I have not tested with any 2.x devices, though the traces are pretty short, I would expect no issues. (All of my easily available 2.x devices are bus-powered, and they won't work for obvious reasons).

This product works as intended for blocking power on the usb, but did not work with the products I had wanted to use it with. But I was impressed with the how sturdy the build quality of this is. I own a Schiit Modius and Bifrost (gen 3 usb), both devices are recognized via usb with this device, but would not output anything. Both devices had independent power of the computers usb. The problem I wanted to solve is either EMI noise or a usb ground loop from a high power gaming computer. When either dac is connected via usb, they pick up a lot of electrical noise when the computer is in high power states. The noise comes through on the Modius even if on a different input, the computer usb has to be completely disconnected (seperate usb power via wall wart and optical from the computer are crystal clear). Unfortunately, the same noise is coming through to the DACs with the power blocked via this device... So the usb is dirty on just the data pins. I have ordered a slightly more expensive usb isolator and filter to try...

TL;DR: It doesn't work with iPhones or apple trackpads. Or pretty much any other self-powered device I have laying around. So, I use an Apple Trackpad with desktop computers - a mac and a pc. If I leave it plugged in via usb, it automatically switches with my KVM. If I don't, I have to manually pair it over bluetooth. After 2 years of being plugged in 24/7, my apple trackpad's battery got bloated, so I'll sadly have to dispose of that one or at least take it apart to get the battery out. We'll see how that goes. In the meantime, I really missed having a trackpad, so I bought another. And I bought this, in hopes that I could use it over USB without charging it. It only needs to be charged once every few weeks, after all! Sadly, without the power source, the trackpad doesn't detect the USB connection. :( So I guess.. 5 star review? I'm sore it doesn't work for my use case, and to be honest, I'm not sure it actually works at all because of that hahaha. Nothing I plugged in detects USB. That's worrisome. Try it anyway? It's only $6.50 and it's a nice little dongle.

Works as advertised. Blocks the power. I use it with an Android Auto external device because the data+power USB port in my car remains active for an extended period after turning off the car. So I added a splice to draw power from another port (that is off when the car is off) and then only allow data in the primary port. Works perfectly.

Cumpre com a sua finalidade

Fait parti d'un petit montage dans la voiture pour alimenter le boitier Android Auto sans fil. Le boitier est bien alimenté uniquement quand le moteur tourne. (la connexion se rétablissait avec le téléphone quand je sortait pour aller dans le jardin ou que je bricolais dans le garage). Problème résolu, ça fonctionne depuis 15 jours.

Excelente produto. Recomendo!

Hace lo que promete.