gefran TPD32-EV-...-4B - Rs485 Serial Interface; Description

—————— TPD32-EV ——————
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4.5 RS485 SERIAL INTERFACE
4.5.1 Description
TheRS485serialinterfaceenablesdatatransferviaaloopmadeoftwosymmetrical,spiralconductorswitha
commonshield.Themaximumtransmissiondistanceis3936feet(1200m)withatransferrateof38,400KBaud.
Thetransmissioniscarriedoutviaadifferentialsignal.
RS485interfacesarebus-compatibleinhalf-duplexmode,i.e.sendingandreceivingtakeplaceinsuccession.
Upto31TPD32-EVdevices(upto128addressselectable)canbenetworkedtogetherviatheRS485interface.
AddresssettingiscarriedoutviatheDevice addressparameter.Furtherinformationconcerningtheparameterstobe
transfered,theirtypeandvaluerangeisgiveninthetablecontainedinsection10,“ParameterList”(RS485column).
TheRS485ontheTPD32-EVseriesdevicesislocatedontheRegulationcardintheformofa9-poleSUB-D
socketconnector(XS).Thecommunicationmaybewithorwithoutgalvanicisolation:byusinggalvanicisolation
anexternalpowersupplyisnecessaryfor+5V.ThedifferentialsignalistransferredviaPIN3(TxA/RxA)and
PIN7(TxB/RxB).BusterminatingresistorsmustbeconnectedatthephysicalbeginningandendofanRS485
businordertopreventsignalreexion.ThebusterminatingresistorsonTPD32seriesdevicesareconnected
viajumpersS12andS13.Thisenablesadirectpoint-to-pointconnectionwithaPLCorPC.
1 2 3 4 11 12 13 20 21 22 23 24 25 26 27 28
1 2 3 4 11 12 13 20 21 22 23 24 25 26 27 28
R-TPD32
33 34
33 34
XS
12
3
45
98 76
150 R
TxA/RxA
TxB/RxB
0VS
+5VS
S12 S13
PE
RS485
100 R
470 R 470 R
+5 V
S19
S18
Figure 4.5.1.1: RS485 serial interface
note!  EnsurethatonlytherstandlastdropofanRS485bushaveabusterminatingresistor
(S12andS13mounted).Inallothercases(withintheline)jumpersS12andS13mustnot
bemounted.WithS18andS19mountedthedrivesupplytheserialline.Thismodalityis
allowedonpoint-to-pointconnectionwithoutgalvanicisolationonly.