Specifications

EssentialsofCrestronProgramming
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Thesubmenualsoincludestheoptiontodisplaythedevicefunctions,whichcanhelp
youverifythatthedeviceprovidestheexpectedcommands.ClickShow
IRFunctionstoviewthecommands.
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Relays
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Manydevicesemployinternalelectronicsthatallowfunctionstobetriggeredthrough a
simpleelectricalcontact.Intheworldofcontrolsystems,thisisaccomplishedusing
relays.Devicessuchasscreens,drapesandprojectorliftstendtousethistypeof
interface.Inaddition,somenot‐dimmedlightingcircuitsca
nbeswitchedonandoff
usingrelays.
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Crestronmanufacturesrelaysofmanydifferentflavors:low‐powerrelaysforusewith
devicesthatdonotdrawalotofcurrentorrequirehighvoltages,andhigh‐powerrelays
fordirectcontrolofmotorsandlightingcircuits.Inaddition,relayscaneit
herbe
mechanicalorsolid‐state.
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Toconfigurearelaydevice,thecontrolsystemmusthavearelaycardinstalled.Most
Crestroncontrolsystemsprovideabuilt‐inrelaycard;forexample,theC2I‐RY8cardis
builtintothePRO2.Itprovideseightlow‐voltagerelayports.Inaddition,Crestron
manufacturesplug‐inre
laycards,suchasCNXRY‐8,thatcanbeinstalledinthe
expansionslotsofthecontrolsystem.