The 25-pin Female D-type 10-slot I/O Bus Expansion Baseplate, IC693CHS392, has several uses. It is basically used as a PLC local chassis but can also be used to extend I/O to other locations close by (called local I/O expansion) that are not more than 50 feet (15 meters) apart. Local I/O expansion allows users to increase a PLC?s I/O and enhances control under the monitoring of a single processor. There is no CPU on the baseplate. Local I/O expansion is a good option for smaller PLC systems with I/O situated close to the local chassis. The IC693CHS392 expansion baseplate has a 25-pin female D-type I/O Bus Expansion connector that is mounted at its right end. This connector is used for making connections to other baseplates. It has 10 slots labeled serially from 1 to 10. The baseplate cannot stand alone. It must be mounted in a CPU baseplate of a system having a CPU, either in a PLC or in a Personal Computer that has a Personal Computer Interface (PCI) Card. The first expansion baseplate is connected to the CPU?s baseplate via a short parallel cable which provides seamless parallel data transfer between the CPU baseplate and the locally expanded I/O baseplates. The type of the CPU determines the maximum number of Expansion baseplates that can be installed in a system. CPUs 331, 340, and 341 allows a maximum of 4 while CPUs 350 and higher can allow up to 7 baseplates. Power must be supplied to the expansion baseplate and must be calculated based on the baseplate?s modules as well as and the local load that will be placed on each baseplate?s power supply. IC693CH392 has a Rack Number Selection DIP switch, must be connected to a common ground and does not support these intelligent option modules: PCM, ADC, BEM330 and CMM311. These modules must be mounted in a CPU baseplate while all other I/O and option modules can be mounted in any type of rack. Technical Specifications Module Type: Expansion I/O Base Baseplate Option: Expansion Distance: Up to 50 feet Number of Slots: 10 Dimensions: 17.44 x 5.12 x 5.59 in. (W x H x D) Internal Power Used: 150 mA @ 5 VDC