The Edwards SIGA-IM2 Isolator Module is an addressable device that protects a signaling line circuit (SLC) from a to wire-to-wire short. The SIGA-IM2 module monitors line voltages and opens the data to detect a short, isolating the short between the two modules located closest to the short. The loop controller assigns an address to the SIGA-IM module. The module uses one detector address on the SLC.