Industrial-Grade RS485 Extender Isolated RS-485 Repeater Isolator Anti-Interference Anti-Surge Guide

Industrial-Grade RS485 Extender Isolated RS-485 Repeater Isolator Anti-Interference Anti-Surge Guide

Description:
Isolated RS-485 repeater is a high-performance industrial-grade RS485 signal amplifier and extender. The product can automatically sense the direction of the data flow and the communication baud rate, without any control or handshake signals, ensuring full transparent transmission of data. The equipment power supply and communication signal are completely isolated, and measures such as surge protection and electrostatic protection are also provided. It boasts long transmission distance, high speed, stable and reliable performance, etc. It is widely used in attendance machines, IC card charging systems, automated control, access control systems, parking lots, canteen sales systems, and highway toll collection systems.

Features:
1. Industrial grade design, complete communication isolation, stable and reliable performance, transmission rate up to 300Kbps
2. Built-in high-quality DC/DC isolated power supply module to achieve electrical isolation between ports
3. Support multi-machine communication, up to 128 nodes can be connected, the longest transmission distance is 1500meter/4921.3ft
4. Data flow automatic control technology, automatically distinguish and control the direction of data transmission
5. Multiple protection measures: ±15KV ESD protection, 600W dual-channel TVS protection 2.5KV communication isolation
6.The power supply has a wide range of 9-36VDC, and has reverse connection protection

Electrical Parameters:
RS485 equipment is suitable for long-term stable operation under typical values. The equipment 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 equipment damage!

- Working voltage: Typical DC 9-36V (limit value DC 36V)
- Rated power: Typical 0.36W (9V/35mA; 12V/27mA; 24V/15mA) (limit value 0.5W)
- Working environment: Typical -30℃ to 80℃, humidity: >95%RH (limit value -40℃ to 85℃)
- Isolation voltage: Typical 2000V (limit value 2500V)
- Interface protection: Typical 600W lightning surge (limit value 600W)
- Load capacity: Typical 1-128 nodes (limit value 128 nodes)
- Communication distance: Typical 0-1500meter/0-4921.3ft (limit value 2000meter/6561.7ft)
- Communication rate: Typical 300bps-115.2Kbps (limit value 300Kbps)
- Dimensions: 100 x 54 x 32mm/3.9 x 2.1 x 1.3"
- Weight: 69g/0.2LB

Package Included:
- 1 x Set of RS485 Repeater

485 Wiring Precautions:
1. 485 communication cable must use shielded twisted pair, preferably multiple strands for spare use. It is recommended that the total length does not exceed 1500m/4921.3ft.
2. The wiring should be as far away as possible from high-voltage wires, not parallel to the power cables, and not to be bundled together.
3. 485 bus must be a hand-in-hand bus structure, and resolutely put an end to star connection and bifurcation connection.
4. If there are more than 30 controllers or cable length is greater than 500m/1640.4ft, it is recommended to use a RS485 repeater.
5. The AC-powered equipment and chassis must be grounded and well grounded.
6. Connect the GND ground of all 485 devices with shielded wires.

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 38～88 ohm/km
- Capacitive reactance 30～50 nanofarad/km
- 2-core shielded twisted-pair cable with a twisting distance of 20mm/0.8" (If the distance of the line is not more than 500meter/1640.4ft, the line standard can be appropriately lowered, but it must be twisted pair)

Bus Restrictions:
It is composed of two or more devices that have physical connections with each other. A maximum of 128 devices are allowed to be connected to the bus. Without a repeater, the bus length is not greater than 1500meter/4921.3ft. The system bus should not be branched. If branching is inevitable, the following requirements must be met:
1. The branch length is not more than 10meter/32.8ft; the total length of the bus does not exceed 800meter/2624.7ft; the total number of devices on the branch line is recommended to not exceed 50pcs.
2. All communication signal lines should be kept away from interference sources as far as possible. The signal lines should be run through weak electric wells. They should not be wired in parallel with strong currents (such as 220V residential power supply) or radio frequency signal lines (such as CATV, large-signal audio lines), and the distance should be greater than 0.5 meter/1.6ft.
3.The joints of all circuits must be connected by welding or screw clamping, and be waterproof and moisture-proof. For example, the butt joints can be welded and wrapped with waterproof tape or sealed with epoxy resin.

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 supply 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.

Meaning of Front Status Indicator:
Power indicator: Red power indicator light. The indicator light is always on after power on
Data indication: Green data indicator light. The indicator light flashes when there is data on the bus

Definition of Terminals:
1. DC9V: power interface
2. G: Isolated RS-485 terminal ground, can be connected to the ground or shielded wire
3. A: RS-485 signal input/output positive terminal
4. B: RS-485 signal input/output negative terminal


Five Recommended Debugging Methods:
First of all, ensure that the equipment wiring is correct and strictly in compliance with the specifications:
1. Common ground method: Use 1 wire or shielded wire to connect the GND ground of all 485 devices, so as to avoid the potential difference between all devices that affects communication.
2. Intermediate segment disconnection method: Check whether the equipment is overloaded and the communication distance is too long. The damage of a certain equipment affects the entire communication line and other reasons by disconnecting from the middle.
3. Separate wire drawing method: Simply pull a wire to the device temporarily, so that it can be used to rule out whether the wiring caused the communication failure.
4. Replace the converter: carry a few converters with you so that you can rule out whether it is a converter quality problem that affects the communication quality.
5. Laptop debugging method: first ensure that the laptop you carry with you is a device with normal communication, and replace the client's computer for communication. If it is possible, it indicates that the serial port of the client's computer may be damaged.