The QUADRA-TONE 500 Series are a high performance signaling device designed to function in situations which require a distinctive tone, such as areas of high ambient noise or where a different sound is required to be distinguished from other nearby signals.
Catalog numbers AU-501, AU-502, AU-503 and AU-504 can be easily wired to sound one of four (4) built-in tones: WHOOP, WAIL, HI-LO or HORN.
The AU-502 is Listed for Life-Safety / Fire Alarm use, while the AU-501, 503 and 504 are listed for General Signaling.

The AU-502 can be powered from either a switchable or a continuous source of 24VDC. By powering the AU-502 from a switchable source (such as the AU-5395), minimum power drain during periods of inactivity can be maintained.
Additionally the 24VDC-power input to the AU-502 is polarity sensitive, allowing for connection to a supervised polarity reversing power source. Tone selection can be permanently wired inside the unit to provide a single tone (or a coded tone using the Horn Sound), or remotely controlled using dry contacts or relay modules.
The AU-503 and AU-504 are normally wired to a continuous source of AC, with a selection jumper wired into the unit to select the tone desired. The tone selection jumper, can be brought outside to allow for remote tone selection using dry contacts.