windows 7 - How to prevent UPS from waking up computer through USB?

I have a Eaton 3S 700 UPS plugged to my Windows 7 Pro 64-bit computer by a USB cable, and I can't prevent the UPS from waking up the computer constantly. This happen both when the UPS is in battery mode and utility power mode while battery charging. The computer wake up automatically a few seconds or minutes after going to sleep mode.

According to the Windows Device Manager settings (Power Management tab), the UPS is not allowed to wake up the computer, only the network adapter and the mouse can :

C:\>powercfg -devicequery wake_armed
Realtek RTL8168D/8111D Family PCI-E Gigabit Ethernet NIC (NDIS 6.20)
HID-compliant mouse

After some tests on USB devices wake ability settings, I found that the issue only occur when a least one USB device (mouse or keyboard) is allowed to wake the computer. When the network adapter (Realtek RTL8168D/8111D Family PCI-E Gigabit Ethernet NIC (NDIS 6.20)) is the only allowed device, the computer stay in sleep mode and will only wake up from either the power button or a wake-on-lan magic packet. But this is just a workaround, I don't want to settle for it.

I grabbed some data just after the system has been awakened by the UPS :

C:\>powercfg -lastwake
Wake History Count - 1
Wake History [0]
  Wake Source Count - 1
  Wake Source [0]
    Type: Device
    Instance Path: USB\ROOT_HUB20\4&28734d27&0
    Friendly Name:
    Description: USB Root Hub
    Manufacturer: (Standard USB Host Controller)

Event viewer :

The system has resumed from sleep.

Sleep Time: 2017-02-18T17:55:45.477601500Z
Wake Time: 2017-02-18T17:56:31.983600900Z

Wake Source: Device -USB Root Hub

I tried almost every tip from here and there (checked scheduled tasks, disabled wake timers, updated video drivers, updated BIOS, tried some control panel power management tweaks, enabled/disabled hibernation, enabled/disabled hybrid sleep) and got absolutely no results. Installing the official UPS management software (Eaton Power Protector) doesn't solve anything neither.

Then I took a look into the BIOS settings and I saw that ACPI 2.0 Support was disabled, so I enabled it and then did a fresh Windows installation on another hard drive (before installing the latest drivers and windows updates). Still no results.

In a last hope, I would like to know if anyone here could solve this issue.
You can download very detailed information on my system configuration (Everest and dxdiag reports) here : https://drive.google.com/drive/folders/0B1ltKLthoSRbZTh4UGdULTFaUE0?usp=sharing

Next to that, I have some other related questions :

• Is it the expected behavior (UPS wakes computer, no matter device manager settings) or could it rather come from a motherboard or UPS design flaw ?


• Why does this issue only affects the UPS and not other USB devices ? Has it something to do with the fact that the UPS is self powered ?

Thanks