ZB-RS485-23 communication transmission cable 4-20mA signal output

ZB-RS485-23 communication transmission cable 4-20mA signal output

ZB-RS485-23 communication transmission cable 4-20mA signal output

Product Description: Shielded twisted pair, conductor made of 2 * 2 * 22AWG multi stranded tinned electrolytic copper wire twisted together, color PP insulation sheath suitable for installation and identification, each pair of wires has aluminum foil/polyester tape overall 99.9% shielding, additional independent multi stranded tinned copper wire grounding conductor, industrial gray PVC outer sheath.

The RS-422 interface is a unidirectional, balanced transmission specification for single machine transmission and multi machine reception, named the TIA/EIA-422-A standard. In order to expand its application scope, EIA developed the RS-485 standard based on the RS422 interface in 1983, which added multi-point and bidirectional communication capabilities, allowing multiple transmitters to be connected to the same bus. At the same time, the driving capability and conflict protection characteristics of the transmitters were increased, and the bus range was expanded. Later, it was named the TIA/EIA-485-A standard. Due to the fact that the recommended standards proposed by EIA are prefixed with "RS", it is still customary in the communication industry to refer to the above standards as RS prefix.

The full name of RS422 interface standard is "Electrical Characteristics of Balanced Voltage Digital Interface Circuits", which defines the characteristics of interface circuits. Actually, there is also a signal ground wire, a total of 5 wires. Since the receiver adopts high input impedance and the transmission driver has stronger driving ability than RS232, it is allowed to connect multiple receiving nodes on the same transmission line, up to 10 nodes can be connected. There is one master device (Master) and the rest are slave devices (Salve), which cannot communicate with each other. Therefore, the RS422 interface supports point to many bidirectional communication. The input impedance of the receiver is 4k, so the load capacity of the transmitter is 10 × 4k+100 Ω (terminating resistance). The RS422 four wire interface, due to the use of separate transmission and reception channels, does not require control of data direction. Any necessary signal exchange between devices can be done through software (XON/XOFF handshake) or hardware (a pair of separate twisted pair cables).