What is an RS-485 cable?
What is an RS-485 cable?
What is RS-485? RS-485 is an industrial specification that defines the electrical interface and physical layer for point-to-point communication of electrical devices. The RS-485 standard allows for long cabling distances in electrically noisy environments and can support multiple devices on the same bus.
How many wires are in RS-485?
RS485 needs 3 conductors and a shield. Many people say it’s a two-wire network but it is not. Two conductors are used to carry the RS485 Differential voltage signal. The Shield is connected to earth/ground at one end only and provides shielding against induced noise.
Is RS485 serial?
RS232, RS422, RS423, and RS485 are all essentially physical layer protocols. They are all serial communication protocols and are ubiquitous device interfaces.
Where is RS485 used?
In computer systems, RS485 is used for data transmission between the controller and a disk drive. Commercial aircraft cabins also use RS485 for low-speed data communications. This is due to the minimal wiring required due to the wiring configuration requirements of RS485.
What voltage does RS485 use?
Standard RS485 transceivers operate over a limited common mode voltage range that extends from –7V to 12V. In a commercial or industrial environment, ground faults, noise, and other electrical interference can induce common mode voltages that exceed these limits.
Is RS485 serial or parallel?
What is the voltage level of RS485?
–7V to 12V
Standard RS485 transceivers operate over a limited common mode voltage range that extends from –7V to 12V. In a commercial or industrial environment, ground faults, noise, and other electrical interference can induce common mode voltages that exceed these limits.
Does RS485 provide power?
Most RS-485 transceivers use either a 5-V supply voltage or a 3.3-V supply voltage. Therefore, the internal power dissipation (not due to loading or switching) can be as high as 200 mW (5 V · 40 mA) for some older generation devices.
Is RS485 synchronous or asynchronous?
The RS232 and RS485 interfaces use asynchronous serial communication. This means that they utilizes start and stop bits in order to know when information is being sent. This is a bit different from the synchronous data communication in which devises must be synchronized at first and then send data continuously.