ATC 277SM User manual

High-SpeedRS-232/RS-485/RS-422
Single-ModeFiberOpticModem
User sManual
MODEL-277SM
(EnglishRev2.2)
1.0Description
TheMODEL277SMwasdesignedtoprovidethemost
versatileconnectionpossiblebetweenanyasynchronous
serialequipmentusing FiberOpticcable.Itallowsanytwo
piecesofasynchronousserialequipmenttocommunicatefull
orhalf-duplexovertwofibersattypicaldistancesupto
20KM.
RS-232datasignalsatup to115.2KbpsandRS-422,or
RS-485 datasignalsatup to250Kbpsaresupported.
Differentstandardscanbemixedand matchedtoallow
RS-232devicestoconnecttoyourRS-422orRS-485
system.ThismeanstheMODEL277SMcanreplace
convertersand isolatorswhenconnecting remotedevices,
whileprovidingtheEMI/RFIandtransientimmunityofoptical
fiber.
TheMODEL277SMsupportsboththeTransmit and Receive
datalines, and providesfullhardwarecontroloftheRS-422
/485driverwithautomaticSend DataControlcircuit.
Timeoutsareautodetectbetween0.10 and2.2ms.Allserial
connectionsareprovidedontheDB-9maleconnectoror
6-bitterminal,whilethesingle-modefiberisconnectedvia
twoSC/ST/FCconnectors.Theunitispoweredby9-24 VDC
at 250 mAmax.
2.0RS-232Connections
ConnectionoftheMODEL277SMissimpleand straight
forward.TheDB9maleserialconnectorisusedforconnect
toRS-232 interface.TheRS-232 signalsaredefinedasa
DTEdevice(inputonPin2andoutputonPin3)
Table1:RS-232ConnectionDiagrams
DB-9Male
(PIN) RS-232
2 RXD
3TXD
5 GND
3.0RS-422&RS-485Connections
Table2:RS-422/RS-485ConnectionDiagrams
6-Bit
Terminal RS-422 RS-485
PIN1 T+ 485+
PIN2 T- 485-
PIN3 R+ NC
PIN4 R- NC
PIN5 VIN VIN
PIN6 GND GND
4.0FiberOpticConnections
TheMODEL277SMusesaseparateLEDemitterand
photo-detectoroperatingat1310nmwavelengthConnections
totheemitteranddetectorareonSC/ST/FCtypeconnectors.
Onefiberisrequiredforeachconnectionbetweena
transmitterandreceiver.Inapoint-to-pointconfiguration,two
fibersarerequiredbetweenthetwomodems,onefordatain
eachdirection.
Themostimportantconsideration inplanningthefiberoptic
linkisthe powerbudget”ofthefibermodem.Thisvalue
representstheamountofloss indBthatcan bepresentin
thelinkbetweenthetwomodemsbeforetheunitsfailto
performproperly.Thisvalueincludeslineattenuationaswell
asconnectorloss.FortheMODEL277SMthetypical
connector-to-connectorpowerbudgetis13dB.Because
9/125um SingleModeFiber cabletypicallyhasaline
attenuationof0.6dBperKmat1310 nm,the13 dBpower
budget translatesinto20KM..
5.0Specifications
TransmissionLine: DualSingle-modeopticalcable
PointtoPointTransmission: Asynchronous,half
orfull-duplex
Interfaces: RS-232,RS-422, orRS-485
DataRates: RS-2320to115.2KBPS
RS-422/4850to250KBPS
Distance : RS-485/RS-422 0-1.2Km
FiberTypicalRange: Upto20KmonSinglemodeglass
fiber
CoupledPowerBudget: 15.0dB
OpticWavelength: 1310nm
FiberConnector: SC(ATC-277SM-SC)
ST(ATC-277SM-ST)
FC(ATC-277SM-FC)
Connectors: DB-9maleforRS-232, 6-Bitterminalfor
RS-422/485connection,
PowerSupply: Requires9 –24VVDC @ 250mA
max.
Operation temperature:-40 -70
EMIandSafety: CE FCC ClassA
Dimensions: 96 Lx66Wx26H(mm)
Weight: 0.40Kg
6.0OrderInformation.
Table3:OrderInformation
P/N: Fiber
Type Wavelength
(nm) Fiber Length(Km)
ATC-277SM-SC SC 1310 20
ATC-277SM-ST ST 1310 20

ATC-277SM-FC FC 1310 20