Product Specification Sheet APS255

Rev. 07/2013

AB913B / AB913C St. Steel Remote Stations (RM5000EX / CB901EX Series)

Model AB913B Shown

Architects' And Engineers' Specifications

The remote station(s) shall be Alpha Communications® / Ring model AB913B (surface) or AB913C (flush) or approved equivalent. Remote(s) shall have clear two-way communications. Remote(s) shall feature a push button (for ringing a bell or acceptance of calls), ultra-sensitive electret microphone, hands-free voice operation and shall require simple home-run wiring. Remote(s) shall be surface wall mounted (model AB913B) or flush mounted (model AB913C) using the BBF863 flush backbox/housing. Unit(s) shall be finished in a stainless steel finish.

Units may be used directly outdoors and are designed to operate in a temperature range of minus 20 degrees to plus 50 degrees Celsius. Up to 10 remote stations may be connected in parallel, on a single call number. Master(s) shall be used with the RM5000EX and/or CB901EX series microprocessor intercom systems.

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

AB913B Surface and AB913C Flush Door Stations
Model AB913C Shown

The AB913B (surface) and AB913C (flush mounted) door stations are tested for external use in temperature from minus 20 degrees to plus 50 degrees C. They both use the same complete internal assembly. The circuit board is specially treated with anti-corrosive compound and fitted in stainless steel wall boxes for optimum protection against water, dust or chemical penetration. External housing are fitted with vandal-resistant locking screws. In function, they are identical, with warning lamp and a single push button. Used in the standard mode, the button closes a contact to operate a separate doorbell or chime circuit. Alternatively, they can be used in "accept" mode by resetting an internal switch. This means, when called, the substation receives a loud-speaking message, but the microphone is not switched on until the accept button is pressed. This is a useful facility in security situations, crew cabins aboard ships, private apartments etc. Both units are designed to work with the RM5000EX and/or CB901EX series microprocessor intercom systems.

  • Loudspeaking handsfree operation
  • Easy installation, screw terminal connections
  • Ultra-sensitive electret microphone
  • Multiple stations in parallel on a single call-number
    • AB913B. Door station, surface.
  • Stainless steel
  • Two-piece stainless steel housing
    • AB913C. Door station, flush-mounted.
  • Stainless steel
  • Flush Backbox (BBF863)
Depth 1.7" (42mm) 
1.6" (40mm)
Width 3.0" (72mm)
5.5" (140mm)
Height 7.9" (200mm)  9.9" (250mm)
Operating Voltage: 24V DC+/- 15%
Frequency range: 300 - 5000 Hz
Galvanic line: 0 dB (1 mW/600 ohm)
Speech level: normal: -12 dBm, max + 4dBm
Tone signalling: according to CCITT norms
External Loudspeaker impedance: 50 ohms
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Due to continuous product improvement, all colors, sizes, materials, finishes and specifications are subject to change without notice.