Problem with CRONTAB file

[Susanne Ramsey]

I have a SUN 4/330 and a SUN 4/470 server on each I have set up cron
entries to do backups at 3am in the morning..  My problem is that at 3pm
it also tries to fire off the program..  Now in the Sun OS Ref manual it
says that the second field in a crontab file is for hours, which can have
values in the range 0 through 23..  So if I say 3 thats 3am not 15 for 3pm
right..????  So why is this thing trying to run at 3pm...  ???  

Here's the entry out of the root crontab file -

30 3 * * * /var/adm/BACKUPS/dump0.com

Please respond to me, if there is intrest I will summarize... 

Many thanks - 
Susanne B. Ramsey