Text to Time

Hi NA2466,

Based on test, current power query seems not support millisecond. In my opinion, I'd like to suggest you split timestamp to multiple columns with different time unit.

Steps:
1. Duplicate timestamp column.
2. Split timestamp to minute and second.
3. Split above second to second and millisecond.
4. add custom column to store real millisecond.(above millisecond *100)

Full query:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjCwMjDUM1OK1YGwjfQMIGwTK2MTPROl2FgA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [ResponseTimeStamp = _t]),
    #"Added Custom" = Table.AddColumn(Source, "Custom", each [ResponseTimeStamp]),
    #"Changed Type" = Table.TransformColumnTypes(#"Added Custom",{{"ResponseTimeStamp", type text}}),
    #"Split Column by Delimiter" = Table.SplitColumn(#"Changed Type", "Custom", Splitter.SplitTextByDelimiter(":", QuoteStyle.Csv), {"Minute", "Second"}),
    #"Split Column by Delimiter1" = Table.SplitColumn(#"Split Column by Delimiter", "Second", Splitter.SplitTextByDelimiter(".", QuoteStyle.Csv), {"Second", "Millisecond * 100"}),
    #"Changed Type1" = Table.TransformColumnTypes(#"Split Column by Delimiter1",{{"Minute", Int64.Type}, {"Second", Int64.Type}, {"Millisecond * 100", Int64.Type}}),
    #"Added Custom1" = Table.AddColumn(#"Changed Type1", "Millisecond", each [#"Millisecond * 100"]*100),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom1",{"Millisecond * 100"})
in
    #"Removed Columns"

You can also refer to below link which has the similar requirement:

Time Duration including milliseconds

Regards,

Xiaoxin Sheng