RS485 standard, Schematic diagram | Schneider Electric Altivar 212

Appendix

RS485 standard

The RS485 standard (ANSI/TIA/EIA-485-A-1998) allows variants of certain characteristics:

•Polarization

•Line termination

•Distribution of a reference potential

•Number of slaves

•Length of bus

It does not specify the connector type or pinout.

The Modbus specification published on www.modbus.org in 2002 contains precise details of these characteristics. They are also summarized in the next sections (Modbus 2-wire and 4-wire standard schematics). The latest generation Schneider Electric devices conform to this specification.

Modbus 2-wire standard schematic

The standard schematic corresponds to the Modbus specification published in 2002 on www.modbus.org (Modbus_over_serial_line_V1.pdf, Nov 2002) and, in particular, to the 2-wire multipoint serial bus schematic.

Schematic diagram

Master

R	G	5 V

650 Ω

650 Ω

0 V

	D1
120 Ω	120 Ω
1n F	1n F
	D0
	Common

R

G

Slave 1

R

G

Slave n

62	S1A53844 01/2011

Image 62

Schneider Electric Altivar 212 manual RS485 standard, Modbus 2-wire standard schematic, Schematic diagram

Contents

Altivar S1A53844 01/2011 Table of Contents Table of Contents Safety Information Important Information About the Book At a Glance Hazard of Electric SHOCK, Explosion or ARC Flash S1A53844 01/2011 Introduction Introduction Topic Hardware setupWhats in this Chapter? Cross section Pin out of the Open Style Modbus connectorRJ45 Tightening torque Pin Signal Connection via Open Style wiring systemPin out of the RJ45 Modbus connector Open Style Reference Connecting cables Connection via RJ45 wiring systemConnection accessories RJ45 Reference Protection Against Interference Description of terminals PTC resistor value F646 GND Hardware setup Configuration Parameters Modbus Adjustment range Default Valid Address Configuration of the communication parametersAccess to the parameters After Control by the Modbus network Configuration of the control sourceParameters Modbus Setting Communication Parameters Setting Default ValidControl by the terminals, monitoring by the Modbus network Parameters Modbus Setting Default Valid LI R selection F112 Parameters Modbus Setting Default Valid AddressCom channel choice F807 Communication Menu COM submenu LI R selection Frequency source Parameters LocationRemote spd ref 2 F207 VIA VIA Complete control diagram Commands CMOd Configuration of the indirect blocks Configuration Configuration of the communication interruption Communication detected fault 16#851 Configure the drive behaviourParameter Modbus Setting Default Valid Address 2129 Configuration Modbus services Slave Slave j Slave k RTU modePrinciple of the Modbus protocol Slave address Function code Data Function 3, quantity = Modbus functions availableRead one word Status info Read indirect blockFunction 3, quantity = 1 Read indirect block of 2 parameters Write Single Register Write multiple registers Function 16 = 16#10, quantity =1 Speed Setpoint Command word Frequency SetpointWrite indirect block Request 6C 7E Response Read Device Identification 43/14 Error response Exception code Modbus services Parameter list Referring to the Altivar 212 programming manual Auto ramp AUI Disabled ManualSetting of Max frequency FH General Setpoints from serial communication Commands from serial communicationList of control parameters Outputs control from serial communication Frequency and speed List of monitoring parametersStatus Current and torque Trip and alarm codes Power and energyMaintenance Values Bit Specifications Remarks CommandsCommand word FA00 Examples Command word 2 FA20Energy reset bit Over-current stall level change bit Speed setpoint FA13 SetpointsFrequency setpoint FA01 Status Status word FE0I Fd01 Status word 2 FE42 Fd42 Command mode status FE45Setpoint mode status FE46 Status word 3 FE49 Fd49 Alarm of run time FE79 Trip and alarm codesAlarm code FC91 Code Value Description Hexadecimal number Decimal number Digital outputs status Fd07, FE07 Monitoring and control of I/O from communicationDigital inputs status Fd06, FE06 Bit Terminal name Function parameter title Damper opening command Digital outputs command FA50Analog outputs command FA51 Analog inputs values FE35, FE36 F580 = 3 Drive model code F805 Model Voltage Power Rating Code FB05 Class FB72bit8Identification ATV212WU15N4C S1A53844 01/2011 Appendix RS485 standard Modbus 2-wire standard schematicSchematic diagram Migration Commissioning Migration ATV21 ATV212For example ATV212Modbus manualENS1A5384401 S1A53844 01/2011