Uses power lines to communicate
These modules, sold in pairs, communicate serially without extra wires or cables. With a DB-9 serial port on one side and a 110/220V power cable slot on the other, they transmit and receive high-frequency signals over power lines using high-pass filters, all with low h.f. output to keep from interfering with electric power on the network. They can transmit data to 500 m at up to 230 kbps, with 56-bit DES data encryption for RS232 signals. The modules are based on a 32-bit RISC processor with 8 MB SDRAM and 4 MB flash memory. They work on 110V or 220V supplies, have built-in surge protectors, and are DTE/DCE selectable.
Saelig Co., Inc.