NGA-504 is a Wall Mounted Addressable Sounder/ Beacon with low power consumption. Up to 32 individually addressed sounders can be installed per loop occupying address 94 to 125. The address is set using switches 1 to 5 of the 8 way DIL switch. Four different tones are available and selected using DIL switches 6 and 7.

When individual address reporting is not required, NGA-504 can be configured as a Shadow Sounder. In this case sounders do not occupy an address in the loop thus freeing up addresses for more detection devices. Shadow sounders do not report back to the control panel so their presence on the loop is not monitored. Shadow sounders draw current from the loop (4.1 mA in alarm) and must be included in loop load calculations.