Rockwell Automation 1756-L6x_L7x ControlLogix System User Manual - Manual (Page 13)

Rockwell Automation Publication 1756-UM001O-EN-P - October 2014 13
Preface
Redundant ControlLogix Controllers
Certain ControlLogix controllers are also supported for use in redundant
systems. For more information about controllers and redundant systems, see
Chapter 12 .
Extreme Environment ControlLogix Controllers
The extreme environment ControlLogix controllers, catalog numbers
1756-L73XT and 1756-L63XT, provide the same functionality as the 1756-L73
and 1756-L63 controllers, but are designed to withstand temperatures
-25…70 °C (-13…158 °F).