"Find" "ChnFind"-method cant use "

English:
Hi all,
I'm new here but cant find a topic that looks my problem.
 
Im scripting in VBS at the moment.
My script searches for outliners and copy them to an new .txt document.
Basicly it work great with ">". But when I use "<" to compare the measurement-data with the limit
find returns "0" as answer. That means "nothing found".
Here a sample about my problem:

 Do'While (ChannelNr < finalcount)

    ChannelNr =  ChannelNr+1
    laengemax =  ChnLength(Ch("[" & ChannelNr & "]/I_" & pruefling &"\15"))      
    var       =  msgboxdisp ("ChannelNr =" & ChannelNr & vbCrlf & "ChnLength: =" & laengemax,"MB_OK", "MsgTypeInformation",0,2)
    intMyResult1   =  1 

    'Hilfe für Schleifen-EXIT
    uebergabecount = 1
    uebergabefind  = 1
    uebergabefind  = chnFind("Ch(""["&ChannelNr&"]/I_"& pruefling &"\15"") < "& iunten   ,1)
                     
    Dowhile uebergabefind <>0

        morefail1       = intMyResult1+1
        intMyResult1    = chnFind("Ch(""["&ChannelNr&"]/I_"& pruefling &"\15"") < "& iunten , morefail1 )
        if morefail1    = 0thenAutoQuit
        if morefail1    = laengemax thenAutoQuit

        pastefail1      = CHV(intmyresult1,"["&ChannelNr&"]/I_"& pruefling &"\15")
        timefail1       = CHV(intmyresult1,"["&ChannelNr&"]/Time")
        intMyHandle1    = TextFileOpen((MyFolders(0)&"Fehlerprotokoll.txt"), eTextFileAttributeWrite )
        intMyText1      = TextfileWriteLn(intMyHandle1, "Zeitstempel:  "& timefail1 &"  Fehler für I < Grenzwert.   I="& pastefail1 &"  !")
                           TextFileClose(intMyHandle1)
                  
        'Hilfe für Schleifen-EXIT
        uebergabecount  =  uebergabefind+1
        uebergabefind   =  Find("Ch(""[" & ChannelNr & "]/I_" & pruefling & "\15"") < " & iunten , uebergabecount )
                      
    loop 'Grenzwert1

loop Until (ChannelNr = finalcount)'Channel
 

 
 
If anyone has an Idea, please inform me (=
 
Thanks a lot.
sincerely Michael