Serial remote I/O slave unit for DL405 PLC
The DL405 offers full-size remote I/O. The goal of remote I/O is to reduce wiring costs by allowing I/O points to be located near the devices they are controlling. The D4-450 has the D4-RM functionality built into the 25-pin port directly on the CPU. However, you can also choose to use the D4-RM.
Here’s how it works:
A special module called the Remote Master is placed in the CPU base. This Master module controls up to seven Remote Slaves. The Remote Slaves are connected to the Master in a daisy-chain manner over a twisted pair communication cable (maximum length 1200m). Each Remote Slave attaches to a DL405 base (any size). Standard DL405 modules populate the remote bases.
You can assign normal input and output addresses to the remote points, or you can assign special remote I/O addresses. The Remote Master sends the remote I/O information to the CPU. The communication between the Remote Master and the CPU is asynchronous to the CPU scan. For this reason, remote I/O applications should be limited to those that do not require the remote I/O points to be updated with every CPU scan.
This product is equivalent to: Texas Instruments / Simatic TI: 405-RIC / U-02RS