Sonalert® SC648

The Mallory Sonalert SC648 Audible Alarm is a compact, electronically driven piezoelectric sounder designed to provide continuous audible notification in electrical control and monitoring applications.

Operating across a 10–48V DC range, the SC648 produces a steady 2,900 Hz tone with a medium sound output, including a rated 68 dB(A) at 2 feet when powered at 10V DC. Unlike pulsing or intermittent alarms, its continuous signal provides a consistent audible indication when the connected circuit activates.

The SC648 features low current consumption of approximately 4–18 mA, allowing integration into control circuits without substantial electrical demand. Its panel-mount configuration and screw-terminal connections support straightforward installation and replacement in equipment enclosures.

For marine applications, the SC648 can be integrated into compatible vessel monitoring systems, electrical distribution panels, and machinery status indicators where a continuous audible notification is required. Its operating temperature range of -30°C to +65°C supports use in a variety of equipment environments, although installation-specific protection may be necessary where moisture or salt exposure is present.