Using an IF statement to insert the time using NOW() but then not update it

[TescoCFCLoader]

I'm working on a spreadsheet to track how many delivery vans I've loaded each day.

The loading sheets have barcodes at the bottom which I scan into my table. They're in the format T<trip><date_as_yyyymmdd>V<van_number>, i.e. T001A20221024V101.

At work the people on the desk have a spreadsheet (on SharePoint) which the manager monitors for loader performance. When our card is scanned to enter our name next to each trip the Start Time (NOW()) is entered by using a circular reference to prevent it from updating.

I'm trying to incorporate that into my own spreadsheet but I can't figure out how to do it - it's either returning the word FALSE or it's inputting the time but updating it. I don't get chance to look at the formulae as it's in constant use from 3:30am until approximately 7:30pm every day (and us loaders aren't allowed behind the desk).

The formula I have (in C2) currently is:

=IF(ISBLANK(C2),IF(ISBLANK(A2),"",NOW()))

and this is returning FALSE in all cells in the row (including those where column A (Scan) is blank).

If I change it to:

=IF(ISBLANK(A2),"",IF(ISBLANK(C2),NOW()))

it still returns FALSE but only in the rows where Scan is not blank.

If I change it to:

=IF(ISBLANK(A2),"",IF(ISBLANK(C2),"",NOW()))

it returns the time but updates on each change I make.

I need it to only enter the time in C2 when A2 is not blank and C2 was previously blank.

 

[jasonb75]

Try

=IF(A2="","",IF(C2="",NOW(),C2))

 

[TescoCFCLoader]

Try

=IF(A2="","",IF(C2="",NOW(),C2))

Brilliant, thanks!
That's what I was missing: C2 if false to override NOW() with the fixed time.