cron job starts after timeout not after definition

Hello

my cron job definition is
'0 35 17 * * *'
so, it should run once a day at 17:35

to prevent maybe an other bug 
(because job starts at 17:34:58 and runs so twice)
so I tried the attribute timeout '30sec'
but with that, the job starts after startup of the program and not at the defined time with defined timeout
> 17:35:30

any ideas? 
thx

greetings 
Klaus