Product Specification Sheet APS1124

Rev. 01/2019

LI424BP Flashing Strobe with Piezo Buzzer for Hearing Impaired

Architects' And Engineers' Specifications

The strobe light unit(s) with built-in Piezo Buzzer shall be Alpha Communications® LI424BP or approved equal. Operation shall be accomplished by placing a call to an apartment intercom (or video-intercom) station. The strobe shall flash for approximately 20-35 seconds after activation of the incoming call signal.

The strobe light shall have a brightness of 15 candela per UL® 1971 (75 candela per UL® 1638). It shall be encased in an attractive, flame retardant type ABS plastic housing. The strobe shall also have a built-in 24vdc Piezo Buzzer.

The strobe light shall meet ADA and UL® requirements for signaling appliances. The strobe shall be powered by the appropriate 24VDC power source (IA543, PK601A or equivalent). Current draw shall be 120mA.

Contractor shall observe all local and national electrical and building codes.

  • Precision engineering
  • Hi-brightness strobe
  • Built-in 24vdc Piezo Buzzer
  • Built-in timer circuitry
  • Multiple applications
  • Low-power operation
  • Easy to install and operate
LI424BP Flashing Strobe with Piezo Buzzer for Hearing Impaired

The Alpha Communications® LI424BP strobe is a high-intensity remote visual signaling device which is typically used with the Alpha Communications® IA543 amplifier apartment intercom systems, and optionally with the Alpha Communications® IA502 multi-entrance transfer relay(s).

Due to its versatility, the LI424BP can also be used as a stand-alone device, which can be triggered by a dry contact pushbutton or dry contact relay closure.

The unit is primarily for use in locations where hearing-impaired persons require supplemental call notification, but can be used anywhere that a visual indication of an incoming call is desired. The bright strobe light flashes once a second for approximately 20-35 seconds when an incoming call is detected (depending on amperage of the 24VDC power supply). This unit will also sound a built-in Piezo Buzzer for as long as the strobe is flashing.

The device can be installed onto a standard 4-inch square electrical box or similar indoor openings. It is not a weatherproof device and therefore should not be used for any outdoor applications. Installation is facilitated by use of simple connections to the pre-mounted circuitry and a complement of mounting hardware.

Required Components
  • LI424B Strobe Unit
  • System Amplifier: may be used with IA543 and related system components (IA502 transfer relay(s), IS and IR apt. stations, AM & VI series or similar entrance panels).
  • PK601A Power Supply (requires SS106 transformer for power). One (1) per system when used with apartment amplifier(s) shown above, or one (1) per unit when used as stand-alone strobe(s), or other equivalent 24VDC power supply.
Dimensions: Height: 5.50" (140mm)
Width: 5.125" (131mm)
Depth (inside wall): 1.50" (39mm)
Projects: 2.125" (54mm) from mounting surface
Construction: Attractive flame retardant type ABS plastic casing
Strobe: 15 candela per UL® 1971, 75 candela per UL® 1638
Power: 24 VDC, 120 mA
Wiring: 18 ga. minimum, 750' maximum
Mounting: Standard 4-inch square electrical box
Alpha Communications
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.