Here's a simple guide on how your pi-top  Hub works and simple checks you can make to ensure it's correctly installed.
A Static green LED light on the Hub confirms power is passing through correctly and has a good connection with the Raspberry Pi and Cooling Bridge.
Take a look at the Getting Started Guide to check your pi-top  build.
Further checks you can make:
- The microSD card has been inserted correctly into the Raspberry Pi and has the latest pi-top Operating System installed.
- The Power Supply Unit has been fully inserted into the back of the pi-top  unit.
- The Cooling Bridge has the correct Thermal Pad attached to the Heat sink and has a good connection with the Raspberry Pi pins and Hub.