gefran TPD32-EV-...-4B - External Devices; Connection Cables

—————— Instruction manual ——————
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- Theinternalpotential0Visconnectedtoterminal11.Inthemajorityofthecasestheinterferencesuppres-
sionisdecreased!
- Theregulationcardputsatyourdisposalthefollowingpowersupplies,whichhaveacommonreference
point:
  +10Vand-10Vforthereference
  +24Vforthepowersupplyofthedigitalinputsandoutputs
  +5Vfortheencoderpowersupply
- Theanalogoutputsaredividedfromtheinternalpotentialthroughadifferentialamplier.Thetwooutputs
oftheoptioncardhavethesamepotential(terminal22and24ofTBOoptioncard).WhentheTBOoption
cardisused,thepotentialoftheanalogoutputsaredivided.Forabetterinterferencesuppressionandforthe
“cleaning”oftheoutputsignals,theterminals2and4oftheTBOoptioncardaredirectlygroundconnected
(terminal10and/or20oftheR-TPD32-EVcard)orviaa0.1µF/250Vcapacitor.
- Thedigitaloutputshavethesamepotential(terminal37)buttheyaredividedfromtheregulatorinternal
potentialviaoptoisolators.Inordertousetheoutputs,itisnecessarytoconnectapowersupplyvoltageto
theterminal30.
- Thedigitalinputsaredividedfromtheregulatorthroughoptoisolators.Theterminals31to34haveterminal
37asacommonpotential.
External devices
Asfortheinstallationofcontactors,protectiondevices,chokes,ltersandotherexternaldevicesitisneces-
sarytofollowtheindicationgiveninthepreviouschapters.Thesametheoryisvalidformotors,encodersand
tachometers.
Connection cables
Theencodershieldedcablemustbemadeoftwistedpairs.Theconnectioncablesoftheencodersandofthe
motors,ifpossible,shouldbeconnecteddirectlytothedevice,withoutgoingthroughsupportterminalstrips.
Theshieldingsofthesignalconductorshavetobegroundconnectedonbothsides.Anyway,forallanalogand
digitalsignalswithverylongconnections(outsidetheelectricboard),itissuggestedtohaveagroundconnec-
tiononlyontheconverterside,inordertoavoidpossiblenoisescausedbytheclosingofthegroundloops.In
particularcasesitcouldbenecessarytoconnecttheshieldingonbothsides,thusgrantingthepointequipoten-
tialityviasuitableconnectioncables.
Theencodercablehastobemadeupoftwistedloopswiththeglobalshieldingconnectedtothegroundonthe
converterside.Avoidtoconnecttheshieldingonthemotorsideconnector.Inparticularcases(cablelongerthan
100meters,strongelectromagneticnoise),itcouldbenecessarytouseacablewithashieldingoneveryloopto
beconnectedtothepowersupplyground.Theglobalshieldinghasalwaystobegroundconnected.