compustar alarm ?

why does this alarm have [acc,starter,ignition] on cn1 .and [acc,starter,ignition] on cn2 thanks    2w900fm-as

the wires on the cn2 is for second [acc, starter, ignition]. some cars required more than one of the listed and you can use those wire in conjunction with a relay to power up the extra wires needed. for example a car might have to ignition wires. you will need the igntion wire on the cn2 connect that wire to a relay and connect the wire off the relay to the igniton 2 wire on the car.