Firmware is software that is installed into the hardware of a device. In this case, it is a way to ensure that your hub and bulbs are running the most current version.
The Sengled Home app will let you know when a firmware update to your hub or bulbs is needed. There will be a red dot next to the “Settings” tab in the bottom right corner on the “Home” screen of the Sengled Home app.
To update your firmware, press “Settings” then press “Firmware Upgrade”.
Note that “Firmware Upgrade” on the “Settings” screen also has a red dot next to it indicating a firmware update is needed.
From here, you will be on the “Firmware Update” screen. Notice the devices that need an update have a red arrow next to them. The devices that have the latest firmware do not have a red arrow next to them.
Press “Upgrade All” and then “Upgrade” to update the firmware of your hub and/or bulbs.
Please note that a hub can take three to five minutes to update. After the update is complete, the hub will turn off and be offline in the Sengled Home app temporarily to install the update—much in the same way a computer will restart after an update. The speed of the update is dependent on the speed of your internet at the location the hub is being used in. Be sure to keep your hub powered on during the update.
Bulbs take six to twelve hours to update their firmware. This is because the bulbs use the ZigBee HA communication protocol. Be sure to leave the bulbs powered on from the light fixture they are being used in during firmware updates.
While firmware is updating, controlling the lights may be on a slight delay. You can still use the bulbs in the meantime.
As we can see from this photo, the hub has successfully updated to the latest firmware. The bulb is still updating its firmware; this is normal since, at the time of this screenshot, it has not been six to twelve hours.
The length of time it takes for bulbs to update is due to the use of ZigBee HA protocol. The protocol does not carry as much data as Wi-Fi, but has a much greater reach.