Reading output from Alarm System using Arduino


I have Texecom Premier 24 installed in my home, which has 8 programmable ports, they manuals says all these ports can be programmed and they are 'Switched 0V' , I'm not sure what does 'Switched 0V' mean, the alarm system runs on 12 V, so now I would like to read the value from those output pins using Arduino but I don't know what would I need as I have very limited knowledge of electronics, the problem is both systems run on different voltage levels, so to read the output from the Alarm system would I need some special circuit with resistors to bring the voltage level down?

I would really appreciate if someone could help me with this.

Thank you,

Do you have a link to the manual?

I might be the case that these ports are volt free contacts, in other words it is just a closing contact with no voltage present . You must post the manual or some more documentation to make sure.