Dissipation Power:0.5w
Supply Voltage:9-36v
Model Number:RS485 Photoelectric isolation
Type:Logic ICs
Condition:New
Wireless transmission speed:Other /other
Isolation typeRS485Repeater
A: product profile
Isolation typeRS485ERepeater is a high - Performance Industrial RS485 signal amplifier. The product can automatically sense the direction of the data stream and the baud rate of communication, without any control or handshaking signals, so that the data can be transparently transmitted. The power and communication signals of the device are completely isolated, with surge protection and electrostatic protection. The utility model has the advantages of long transmission distance, high speed, stable and reliable performance, etc.. Widely used in attendance machine, IC card charging system, automatic control, access control system, parking lot, canteen meal system, highway toll system.
Two: product features
1, industrial design, communications completely isolated, stable and reliable performance,Transmission ratemostUp to 500Kbps;
2 built-in high quality DC/DC isolated power module to realize the electrical isolation between ports;
3,Support for multicomputer communicationIt can connect up to 128 nodes, the maximum distance is 1200 meters;
4 data stream automatic control technology, automatic discrimination and control of data transmission direction;
5, multiple protective measures:ESD protection for positive and negative 15KV600W dual TVS protection, 2.5KV communications isolation;
6, the power supply range of 9-36VDC, and has anti reverse protection;
Three: electrical parameters:
The RS485E device is suitable for stable long-term running in the recommended value; equipment work will not be damaged in the limit value, but may lead to decreased performance; at any time not to exceed the limit value, otherwise it may cause damage to the equipment!
| Item / parameter | Recommended value (typical value) | Limit value |
| working voltage | DC:9-36V | DC:9-36V |
| Rated power | 0.36W (9V/35mA; 12V/27mA; 24V/15mA) | 0.5W |
| working temperature | -30C70C | -40C80C |
| Responsible ability | 1-128 node | 128 node |
| Communication distance | 0-1200 meters | 1200 meters |
| Communication speed | 300-500K BPS | 500Kbps |
Four: 485 wiring notes:
1.485 communication lines must use shielded twisted pair, preferably multi stock standby, with a total length of not more than 1200 meters.
2., wiring as far as possible from the high voltage wire, do not parallel with the power line, but also can not be tied together.
3.485 bus must be hand in hand bus structure, and resolutely put an end to star connection and fork connection.
4. more than 30 controllers or lines longer than 500 meters, you must use 485 repeaters.
5. AC power supply equipment and chassis must be true grounding, and good grounding.
6. connect the GND of all 485 devices with shielding wire.
7. on the last 485 device, 485+ (A) and 485- (B), and the termination resistance of 120 ohms.
Five: communication using RS-485 bus wire selection requirements:
Using 2 core shielded twisted pair
Copper, wire diameter 0.5 to 0.75 mm2,
Impedance 38~88 ohms / km,
30 ~ 50 nanofarad capacitance / km,
A 2 core shielded twisted pair with a distance of 20 mm (if the line is no more than 500 meters) may reduce the line standard but must be twisted pair
Six: bus limit:
Consisting of two or more devices that are physically connected to each other, the bus allows up to 128 devices to be hooked up, and the length of the bus is no more than 1200 meters without repeaters. The branch of the system bus should not be present. If branches are unavoidable, the following requirements must be met:
The length of the 1. branch shall not be greater than 10 meters; the sum of the length of the bus shall not exceed 800 meters; the total number of equipment on the branch shall not exceed 50.
2. of all communication signal lines should be kept away from the interference source, signal line should not weaken electric wells, and power (such as the 220 volt residential power) or a radio signal line (such as CATV, audio signal line) parallel line, if the parallel line, the distance should be greater than 0.5 meters.
Contact 3. all lines must use wire or screws tight connection and welding, waterproof and moistureproof processing, for example, can be used after welding butt joint waterproof tape or tightly sealed with epoxy resin processing.
Seven: signal common ground:
1. all devices on the same network segment must have unified signal ground to avoid common mode interference.
2. centralized power supply, the same network segment of all the power supply (including communication equipment with its own power supply) directly connected to the DC negative to form a common signal,
At this point the signal is the DC source.
3.When single power is supplied independently, the ground (black wire) pins of all the bus devices on the same network segment are connected together to form a common signal ground.
Eight: wiring diagram
Nine: how many debugging methods are recommended?:
First of all, make sure that the equipment is properly wired and strictly compliant:
1, common ground law: with 1 lines or shielding lines all 485 devices connected to GND, so you can avoid potential influence the communication between all equipment.
2, terminal resistance method: in the last 485 devices on the 485+ and 485-, and connect 120 ohm terminal resistance to improve the quality of communication.
3, intermediate section disconnection method: by breaking off from the middle to check whether the equipment is too heavy, the communication distance is too long, the damage of a device to the whole communication line and so on.
4, individual pull method: simple, simple, temporarily pull a line to the device, so that can be used to exclude whether the wiring caused communication failure.
5, replace converter method: carry a few converters, so that you can rule out whether the quality of the converter, affecting the quality of communication.
6, notebook debug method: first is to ensure the normal communication equipment to carry their own notebook computer, replace the customer computer to communicate, if you can, then the customer computer serial may be damaged.
