How to fix my alarm?

My area was hit by a power serge and it blew my alarm , amoung other things , when i checked the alarm the main board seemed fine , fuses were in tacted , however when i checked the transformer the fuse was blowen , so i replaced it and the alarm came on, but as soon as 1 of the sensours got tripped the alarm turned off, and the fuse blew. do i need a new transformer or how would i fix it otherwise?