Programmable Logic Controllers (PLC) 

They employ Modicon 800 series housings, interfaces and I/O modules. These PLCs ’ are supported by the same instruction set as the other 984 models, and are programmed by Modsoft panel software. All of these units have a built-in power supply. All of these units are fully compatible with the Modicon 984 PC instruction set, and solve user logic at a rate of from 1 ms to 2.5 ms per thousand nodes of user logic. The 785El785Dl785K are 24-bit CPUs ’ and the rest are 16-bit CPUs. ’

These units have two, or three built-in Modbus ports for data transfer and remote programming. Through these ports, communication processing on the CPU board links the controller to multiple supervisory and programming devices such as a host computer or Modicons ’ programming panel. The two Modbus ports allow you to connect more than one Modbus device to the controller. Some models have both a single Modbus port and a second port for the Modbus Plus high speed Local Area Network. While others have two Modbus ports and one Modbus Plus port. The DIP switch for setting the Modbus Plus port address can be accessed through the bottom of the modules ’ case. User memory is backed up by a lithium battery which has a conservatively rated service life of one year. Once energized, the BATTERY LOW indicator will come ON when the battery has 14 days left before it will be effectively drawn down. The battery has a five-year shelf life.