Feature: 1. Industrial‑grade design, complete communication isolation, stable performance and transmission rate up to 115.2Kbps. 2. Built‑in DC/DC isolated power supply module to achieve electrical isolation between ports. 3. Support multi‑machine communication, each channel can connect up to 128 nodes, and the longest transmission distance is 2500 meters. 4. Data flow automatic control technology, automatically distinguish and control the data transmission direction. 5. Multiple protection measures, plus or minus 15KV ESD protection, 600W dual‑channel TVS protection 2.5KV communication isolation. 6. The power supply has a wide range of 9-24VDC and has anti-reverse protection. Specification: Item Type: Repeater Compatibility: Compatible with RS-232, RS-485TIA/EIA standards Working Voltage: DC: 9-24V Rated Power: 0.5-1.2W Input Interface: 1 RS-232/1 RS-485 Output Interface: 4 RS-485 Load Capacity: 128 nodes per interface Communication Distance: 2500 meters shielded wire or twisted pair wire per interface Communication Rate: 300bps-115.2Kbps Installation Method: 35mm rail installation, 4-hole installation on the back plate Structure Size: Approx. 115 x 90 x 40mm / 4.5 x 3.5 x 1.6in Working Environment: -30℃ to 70℃ relative humidity>95%RH Wiring Notes: 1. 485 communication line must use shielded twisted pair, preferably multiple strands for spare, the longest is not more than 2500 meters. 2. The wiring should be as far away as possible from high-voltage wires, not parallel to power lines, and not to be bundled together. 3. 485 bus must be a hand-in-hand bus structure, and resolutely eliminate star connection and bifurcation connection. 4. If there are more than 30 controllers or the cable length is greater than 500 meters, it is recommended to use a 485 repeater. 5. The AC-powered equipment and the chassis must be grounded and well grounded. 6. Connect the GND ground of all 485 devices with shielded wires. Requirements For Wire Selection Using RS-485 Bus For Communication: Use 2-core shielded twisted pair cable Copper, wire diameter 0.5～0.75 square millimeter, Impedance 38～88Ω/km, Capacitive resistance 30～50nF/km, 2-core shielded twisted-pair cable with a twisting distance of 20 mm (if the line distance is not more than 500 meters, the line standard can be appropriately reduced, but it must be a twisted pair) Signal Common Ground: 1. All devices on the same network segment must have a unified signal ground to avoid common mode interference. 2. For centralized power supply, directly connect the DC negative poles of all power supplies on the same network segment (including the self-contained power supplies of communication equipment) to form a common signal ground. At this time, the signal ground is the DC power ground. 3. When a single home supplies power independently, connect the ground (black wire) pins of all bus devices on the same network segment together to form a common signal ground.. Package List: 1 x Repeater Note: The device is suitable for long‑term stable operation under the recommended value; the device will not be damaged when working under the limit value, but may cause performance degradation; do not exceed the limit value range at any time, otherwise it may cause damage to the device