Allen-Bradley 1756-L55M24 is a processor module for the ControlLogix platform. The ControlLogix system provides processing, security, motion, discrete and drive control, and enhanced I/O in a compact package. Modular architecture enables efficient design and modification. The ControlLogix system consists of a chassis that contains the processor module (also known as the controller) and the I/O module. There are a number of communication modules available that can be installed in the system chassis to enable communication with other networks. The ControlLogix system is very flexible: multiple controllers can be installed in a single chassis, and I/O can be installed in distributed locations and connected via I/O links.
The 1756-L55M24 can be installed in any slot in the system chassis. In addition, the controller can be installed or removed while the chassis is powered on. However, inserting or removing a module in a dangerous location is dangerous and may result in an explosion. Therefore, in hazardous locations, the power supply to the system should be disconnected before installing or removing the controller. The 1756-L55M24 controller has 3.5 MB of non-volatile user memory, so it can be used without a battery. It has an integrated RS-232 serial port for communication. Optional communication modules include Ethernet, DeviceNet, ControlNet, DH+, SynchLink, and Remote I/O.
