I have made a control box for my pool pump. The buzzer is 110 mA the power needed is 12 Volt backup battery and 12 volt wall wart.

Do I need to place a fuse in the circuit, inside of the control box?

For instance, if the wall wart goes bad or too much voltage goes through the power jack, it may make the battery explode or get real hot! It may be a fire hazzard.

If so, what kind or type of fuse or breaker would I place in line for 110 ma buzzer and 12 volt wall wart?

Here is a photo!

 

Are you charging the battery with this circuit?

 

I am not trying to charge the battery. I was trying to figure out what to do about that problem.

Do you have any ideas? Is there a switch that I can get or something?

 

I guess I need to put in 2 diodes, to correct the problem, right?

One between the adapter power wire and one between the battery, I guess!

What about some sort of fuse?

 

Yes, you will need two diodes to keep the adapter from charging the battery, and to keep the battery from discharging through the adapter.

It wouldn't be a bad idea to fuse both the adapter input and the battery + terminal connection. From the looks of things, a 250mA (1/4A) fuse for each would do the trick.

If you're using a sealed lead-acid battery, it will be dead within a month or two without a charging circuit.