Ascom a51 Alarm Transmitter

A rugged, easy-to-use and portable alarm transmitter equipped with smart personal alarm capabilities.

Ascom a51 is a durable alarm transmitted designed with advanced personal safety in mind. If for some reason you cannot trigger a distress alarm manually, this smart pocket-sized portable device can automatically trigger “man-down” or “no-movement” alarm signals.  For extra safety, a pull-cord triggers a distress alarm if the handset is forcibly taken from staff.  The Ascom a51 also features an optional on-site positioning function. The location can be transmitted together with distress signals, helping the rescue team to determine where the incidence has occurred.


Ascom a51 Alarm Transmitter technical specification

Standard Features

  • Robust and shock resistant
  • Personal alarm
  • 2 push-buttons for configurable alarms
  • Safety Pull-cord alarm
  • Man-down and no-movement alarm (option)
  • 2-tone coustic location signal (ALS)
  • SIM card for identity and personal settings
  • Location function (IR and LF) (option)
  • Battery check function
  • Internal antenna
  • Vibrator alert


  • Size (h× w × d):   85 × 57 × 33 mm incl. clip
  • Weight:   93 g incl. battery
  • Colors:  Steel Grey / Ice blue
  • Display:   LCD Dot matrix
  • Clip:   Hinge-type (standard) or swivel-type


  • Operating temperature:   -10°C to +55°C
  • Storage temperature:   -20°C to +70°C
  • Enclosure protection:  IP40, EN60529
  • Free fall test:     IEC 60068-2-32, procedure 1,  Dropped 12 times from 1.5 meter

Supporting documents

Ascom a51 data sheet

Ascom a51 data sheet

Heavyweight protection in a lightweight package