The catalog number 849A-ZAD24 is an order reference for a timer component from the 849A series by Allen-Bradley/Rockwell Automation. The unit falls into the pneumatic category of timers and counters. The 849A-ZAD24 timer unit features an “on delay” capability and it operates on an input voltage range of 110 to 120 Volts. The maximum voltage of the unit is 600 Volts AC and the line frequency is 60 Hertz. The 849A series timers feature a timing range of 0.05 to 180 seconds. The 849A-ZAD24 timer unit has an open enclosure and it weighs around 2 kilograms (4.5 pounds). The standard ambient temperature range is 0 to 104 degrees Fahrenheit (-17 to 40 degrees Celsius) but this timer can handle a wide temperature range of as much as -20 to 150 degrees Fahrenheit (-28 to 65 degrees Celsius) under certain circumstances.

The Allen-Bradley/Rockwell Automation 849A-ZAD24 timer unit is intended for industrial usage and it provides double timing units along with visual contacts that may be helpful in certain situations. Also, the 849A series timers support the use of auxiliary contacts for applications where these are necessary. The auxiliary contacts are available as a set of instantaneous auxiliary contacts (1 NO, 1 NC) and as 2 sets of instantaneous auxiliary contacts (2 NO, 2 NC). Usually, auxiliary contacts are rated at 5 Amps and 115 Volts or at 1 Amp and 230 Volts. The 849A series timers feature contact ratings that include a continuous carrier current rating of 10 Amps and a closure rating of 7200 Volt-Amps and an opening rating of 720 Volt-Amps.