SQL> select to_date('1259','HH24MI') from dual;

TO_DATE('1259','HH2
-------------------
2010-08-01 12:59:00

SQL> select to_date('1364','HH24MI') from dual;
select to_date('1364','HH24MI') from dual
               *
ERROR at line 1:
ORA-01851: minutes must be between 0 and 59


SQL> select to_date('2515','HH24MI') from dual;
select to_date('2515','HH24MI') from dual
               *
ERROR at line 1:
ORA-01850: hour must be between 0 and 23