Don't Change the Channel Silver
While Channeling gain — Shield every second. It decays when you are not Channeling.
Total Shield: —
Total Shield: —
— marks a value the game fills in during a match: it depends on your stats or counts what happens. Your in-game tooltip shows it.
Patch 16.21 (PBE) — test-server data, may change before release. Text and values from the game files via CommunityDragon (16.21.8264391+branch.main.content.beta).