Count consecutive, non zero values in a column

Well, you stated "anything"... :smileywink:

Below some rather complicated Power Query M-code that generates base data and creates the frequency distribution.

I wasn't sure about the 12-border; I put 12 in the upper group, based on your bin-values.

The trick with consecutive values is to add argument GroupKind.Local to Table.Group as indicated in the comments.

let
// First some lines to generate data
    Source = List.Random(1000),
    #"Converted to Table" = Table.FromList(Source, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
    #"Renamed Columns" = Table.RenameColumns(#"Converted to Table",{{"Column1", "Downtime_hrV"}}),
    #"Added to Column" = Table.TransformColumns(#"Renamed Columns", {{"Downtime_hrV", each _ + 0.45, type number}}),
    #"Rounded Off" = Table.TransformColumns(#"Added to Column",{{"Downtime_hrV", each Number.Round(_, 0), type number}}),
// Now we have base data

// Group By via UI, adjusted by adding GroupKind.Local to get consecutive results
    #"Grouped Rows" = Table.Group(#"Rounded Off", {"Downtime_hrV"}, {{"Count", each Table.RowCount(_), type number}},GroupKind.Local),

// Standard filtering on value 1
    #"Filtered Rows" = Table.SelectRows(#"Grouped Rows", each ([Downtime_hrV] = 1)),

// Group By on Count via UI, code extended with null and the (x,y) function to adjust values to 1 (<6), 2 (<12) or 3 (>=12): 
    #"Grouped Rows1" = Table.Group(#"Filtered Rows", {"Count"}, {{"Frequency", each Table.RowCount(_), type number}}, null, (x,y) => Value.Compare(List.Count(List.FirstN({1,6,12}, each _ <= x[Count])),List.Count(List.FirstN({1,6,12}, each _ <= y[Count])))),

// Add group labels
    #"Added Conditional Column" = Table.AddColumn(#"Grouped Rows1", "Group", each if [Count] < 6 then "1-5" else if [Count] < 12 then "6-11" else ">=12" ),

// Select Group and Frequency
    #"Removed Other Columns" = Table.SelectColumns(#"Added Conditional Column",{"Group", "Frequency"})

in
    #"Removed Other Columns"