RS-422StandardTIA/EIA-422Physical MediaTwisted PairNetwork TopologyPoint-to-point, Multi-droppedMaximum Devices10 (1 driver & 10 receivers)Maximum Distance1500 metres (4,900 ft)Mode of OperationDifferentialMaximum Binary Rate100 kbit/s – 10 Mbit/sVoltage Levels−6V to +6V (maximum differential Voltage)Mark (1)Negative VoltagesSpace (0)Positive voltagesAvailable SignalsTx+, Tx-, Rx+, Rx- (Full Duplex)Connector typesNot specifiedRS-422, also known as TIA/EIA-422, is a technical standard originated by the that specifies electrical characteristics of a digital signaling circuit. Can transmit data at rates as high as 10, or may be sent on cables as long as 1,500 meters. Some systems directly interconnect using RS-422 signals, or RS-422 converters may be used to extend the range of connections. The standard only defines signal levels; other properties of a serial interface, such as electrical connectors and pin wiring, are part of the and standards. Contents.Standard scope RS-422 is the common short form title of (ANSI) standard ANSI/TIA/EIA-422-B Electrical Characteristics of Balanced Voltage Differential Interface Circuits and its international equivalentITU-T Recommendation T-REC-V.11, also known as X.27. These technical specify the electrical characteristics of the balanced voltage digital interface circuit. RS-422 provides for data transmission, using, with unidirectional/non-reversible, or non-terminated transmission lines, point to point, or multi-drop.
Converters RS-232 to RS-422/RS-485 Interface Modules are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for Converters RS-232 to RS-422/RS-485 Interface Modules.
In contrast to, RS-422/V.11 does not allow multiple drivers but only multiple receivers.Revision B, published in May 1994 was reaffirmed by the in 2005.Characteristics. Data Rate / Line Length chart from RS-422 Annex ASeveral key advantages offered by this standard include the differential receiver, a differential driver and data rates as high as 10 Megabits per second at 12 meters (40 ft). Since the signal quality degrades with cable length, the maximum data rate decreases as cable length increases. Figure A.1 in the annex plotting this stops at 10.The maximum cable length is not specified in the standard, but guidance is given in its annex.
(This annex is not a formal part of the standard, but is included for information purposes only.) Limitations on line length and data rate varies with the parameters of the cable length, balance, and termination, as well as the individual installation. Figure A.1 shows a maximum length of 1200 meters, but this is with a termination and the annex discusses the fact that many applications can tolerate greater timing and amplitude distortion, and that experience has shown that the cable length may be extended to several kilometers. Conservative maximum data rates with 24AWG UTP cable are 10 Mbit/s at 12 m to 90 kbit/s at 1200 m as shown in the figure A.1. This figure is a conservative guide based on empirical data, not a limit imposed by the standard.RS-422 specifies the electrical characteristics of a single balanced signal. The standard was written to be referenced by other standards that specify the complete DTE/DCE interface for applications which require a balanced voltage circuit to transmit data. These other standards would define protocols, connectors, pin assignments and functions.
Standards such as ( connector) and ( connector) use RS-422 electrical signals. Some RS-422 devices have 4 screw terminals for pairs of wire, with one pair used for data in each direction.RS-422 cannot implement a true multi-point communications network such as with since there can be only one driver on each pair of wires. However one driver can to up to ten receivers.RS-422 can interoperate with interfaces designed to, but they are not identical. RS-422 uses a nominal 0 to 5 signal while MIL-STD-188-114B uses a signal symmetric about 0 V.
However the tolerance for common mode voltage in both specifications allows them to interoperate. Care must be taken with the termination network.is a similar specification for unbalanced signaling.When used in relation to communications wiring, RS-422 wiring refers to cable made of 2 sets of, often with each pair being shielded, and a ground wire. While a double pair cable may be practical for many RS-422 applications, the RS-422 specification only defines one signal path and does not assign any function to it. Any complete cable assembly with connectors should be labeled with the specification that defined the signal function and mechanical layout of the connector, such as.Applications The most widespread use of RS-422 was on the early computers. This was implemented in a multi-pin connector that had enough pins to support the majority of the common pins; the first models used a 9-pin, but this was quickly replaced by a -8 connector. The ports could be put into either RS-232 or RS-422 mode, which changed the behavior of some of the pins while turning others on or off completely. These connectors were used both to support RS-232 devices like, as well as networking, RS-422 printers, and other peripherals.
Two such ports were part of every Mac until they were replaced, along with ports, by on the in 1998.RS-422 is a common transport mechanism for RS-232 extenders. These consist of RS-232 ports on either end of an RS-422 connection.Before hard disk based playout and editing systems were used, systems and facilities used RS-422A to remotely control the players/recorders located in the.
In most cases the connection was used, which makes use of a standard connector. This is the industry standard connector for RS-422, which is still found on much broadcast equipment today.See also.References This article is based on material taken from the prior to 1 November 2008 and incorporated under the 'relicensing' terms of the, version 1.3 or later.
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Warranty. Technical Support. Partners. Enviromental Policy. News & Events. About Us. The PSM-ME-RS232/RS485-P bi-directionally converts RS-232 interface signals to the RS-485 2/4-wire and RS-422 standard.With support for 4-wire balanced full duplex communication, or 2-wire half-duplex, the PSM-ME-RS232/RS485-P is suitable for most applications, including industrial, commercial and any general office computer device.
Transmission speeds of 1.2 kbps up to 115.2 kbps can be applied to point-to-point and point-to-multipoint networks.Use the PSM-ME-RS232/RS485-P in all common bus systems with UART/NRZ data format and character length of 10/11 bits. This is the best “plug and play” solution for converting RS-232 (V.24) to RS-422 (V.11) and RS-485, with electrical isolation. RS232 to RS485 Converter Features.
RS-422 4-wire for point-to-point operation. RS-485 2-wire operation, half duplex. RS-485 4-wire operation, full duplex. Automatic transmit/receive changeover. Transmission speed from 1.2 kbps up to 115.2 kbps. Integrated data indicator for dynamic indication of transmit and receive data. High-quality 3-way isolation between power supply, V.24 (RS-232), and RS-422/485 for reliable decoupling of the potentials with 1.5 kV.
Integrated surge protection with transient discharge to the DIN rail. Shipbuilding approval per DNV.
PSM-ME-RS232/RS485-P Technical Specifications Serial interfaceInterface 1V.24 (RS-232) interface in acc. With ITU-T V.28, EIA/TIA-232, DIN 66259-1Connection methodD-SUB 9 plugTransmission length15 m (shielded twisted pair)Conductor cross section flexible min.0.2 mm²Conductor cross section flexible max.2.5 mm²Conductor cross section AWG min.24Conductor cross section AWG max.12Pin assignmentDTE/DCE switchover via switchProtocols supportedtransparent protocolSerial transmission speed1.2; 2.4; 4.8; 7.2; 9.6; 19.2; 31.25; 38.4; 57.6; 75; 93.75; 115.2 kbpsInterface 2RS-422 interface in acc. With ITU-T V.11, EIA/TIA-422, DIN 66348-1Connection methodPluggable screw connectionTransmission length1200 m (shielded twisted pair)Termination resistor390 Ω150 Ω390 Ω (Can be connected)Conductor cross section flexible min.0.2 mm²Conductor cross section flexible max.2.5 mm²Conductor cross section AWG min.24Conductor cross section AWG max.13Protocols supportedtransparent protocolSerial transmission speed1.2; 2.4; 4.8; 9.6; 19.2; 38.4; 57.6; 75; 93.75; 115.2 kbpsInterface 3RS-485 interface in acc. With EIA/TIA-485, DIN 66259-1Connection methodPluggable screw connectionData direction switchingAutomatic control or via RTS/CTSTransmission length1200 m (shielded twisted pair)Termination resistor390 Ω150 Ω390 Ω (Can be connected)Conductor cross section flexible max.2.5 mm²Conductor cross section flexible min.0.2 mm²Conductor cross section AWG max.14Conductor cross section AWG min.24Protocols supportedtransparent protocolSerial transmission speed1.2; 2.4; 4.8; 9.6; 19.2; 38.4; 57.6; 75; 93.75; 115.2 kbpsAmbient ConditionsAmbient temperature (operation)-40 °C. 70 °CAmbient temperature (storage/transport)-40 °C. 85 °CPermissible humidity (operation)10%.