I am experiencing a weird issue with my QA403.
I have tried with both the latest 1.209 version, as well as, the latest stable 1.202
The firmware is version 60
After hardware reset the device seems to be functioning properly when in run mode for a couple of minutes, but at some point it will exit the run mode and any attempt to start again will immediately result in exiting the run mode. The software does not report any error, but rather reports the device to be back in “Ready” mode! The only way to fix this issue is to manually disconnect and reconnect the device, or use “Reset Hardware” from the hidden debug menu.
Do I have a faulty device?
Thank you in advance for your attention and support.
OK, after further investigation I have an update.
I’ve used a USB-3 Hub that has the ability to deliver up to 60W of power! (Sarbent USB 3.0 7-port hub). When I use a really short USB cable to connect the QA403 to the hub, I am getting USB voltage more than 5V and the device exhibits the weird behavior of refusing to run after a few minutes. However, using a longer cable (6 ft +) the reported USB voltage is below 5V (4.9) and the device seems to operate normally indefinitely.
Hopefully this is helpful for any others who may experience a similar issue.
Also, please don’t hesitate to propose any additional testing that I can perform to further investigate / troubleshoot the root cause.
Hi @etl17, the QA40x won’t care if the voltage is a bit above 5V. If it’s more than 5.4V you might start hurting the life span of some of the internal regulators. But the QA40x should operate the same from a reported voltage of about 4.6 to 5.2V. Below 4.6V you’ll see the USB voltage turn orange and below ~4.5V it’ll turn red. These are telling you that the internal regulators may have dropped out of regulation and so measurements may have been compromised.
If you are in the 4.6V to 5.2V range and you are experiencing connection issues that are cable dependent, I’d suspect the USB cable data wires are intermittent.