Size archive log different with online redo log

Dear Experts,

I had a problem with archive redo log size. I saw the size between archive redo log and online redo log is different.

The online redo log on path /oracle/SID/origlogA/log_g17m1.dbf , the size is 280MB, but on archive log the size just 130MB.

Why the size different? How to change the archive redo log?

We are running with Oracle 11.2.0.4.

Please aid me to solve this issue.

Thanks

Edy