Please use the following report, to see how long an asset has been on.
Select Top 1000000 tblAssets.AssetID,
tblAssets.AssetName,
Convert(nvarchar(10),Ceiling(Floor(Convert(integer,tblAssets.Uptime) / 3600 /
24))) + ':' +
Convert(nvarchar(10),Ceiling(Floor(Convert(integer,tblAssets.Uptime) / 3600 %
24))) + ':' +
Convert(nvarchar(10),Ceiling(Floor(Convert(integer,tblAssets.Uptime) % 3600 /
60))) As [uptime day:hour:minutes]
From tblAssets
Order By tblAssets.AssetName