HITEC PMAC 3000 - Encoder (Optional)

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PMAC 3000 Page11
Encoder(optional)
ThePMAC 3000isavailablewithanencoderoption.Thisoptioniseasilyverifiedatpower  up
whenthesoftwareversionisdisplayedintheStartupScreen.SeeFigure2.Attheendofthe
softwareversion,“‐E”willappear.
TheencoderversionworkswithquadratureencoderswithsingleendedTTL/CMOSoutputs.It
powerstheencoderwith5VDC.
Therearethreemodesofoperationthatrelatetotheencoder.ThesemodesareOff,Angleand
RPM.HowtoselecttheappropriatemodeisdiscussedintheMenusectionlaterinthismanual.
In the Off mode, the PMAC 3000 behaves just like it would with the standard software (no
encodersoftware).IntheAnglemode,allencodermeasurementsaremade indegrees.Inthe
RPMmode,allencodermeasurementsaremadeinRPM.InthecaseofAngleandRPMmodes,
thedisplayissplit suchthatthesensorreadingisontheleftandtheencoderreadingontheright.
Theappropriateunitsareshownbelowthecorrespondingreading.
The encoder version provides for encoder limits, just like those provided for the load sensor.
TheselimitsareLow,Ok,HighandTarget.Ineachcase,theyareevaluatedinthesamewaythat
thesensorlimitsareevaluated.InthevariousPeakmodes,allthelimitsareevaluatedafterthe
processconcludes, whiletheTargetlimitisevaluatedinrealtime.IntheRecordmodes,onlythe
Targetlimitisevaluated.Asbefore,inthe Recordmodes,the Targetlimitis evaluatedinreal
time.IntheTrackmode,alllimitsareevaluatedinrealtime.
IntheTrackmode,Angle beginscountingimmediatelyandmayberesettozerobypressingthe
Tarebutton.NotethatpressingtheTarebuttonalsozero’sthesensorwhenrunninginRelative
mode.RPM,byitsnature,cannotbezeroed.
InthePeakmodes,Anglebeginscountingfromzeroassoonasthesensorloadhascrossedthe
Thresholdvalueandanewcycle  hasstarted.Asbefore,ifthesensorloadexceedstheTarget
level,thetargetoutputwillfire.InAnglemode,any
AnglereadingexceedingtheencoderTarget
value will  also cause the Target output to fire.After the cycle completes, the sensor value is
evaluatedwithrespecttothesensorlimits,and theAnglevalueisevaluatedwithrespecttothe
encoderlimits.InRPMmode,theRPMismonitoredthroughout
thePeakcycle,buttheRPMis
not zeroed at the start of it.As in Angle mode,if the RPMvalue exceeds the encoder Target
value,theTargetoutputwillfire.Afterthecycleiscomplete,theRPMvalueisevaluatedwith
respecttotheencoderlimits.Ineithercase,
AngleorRPMmode,anencoderlimitfailurewill 
trigger the corresponding output and will light the corresponding limit indicator on the front
panel.ItisthereforepossibletohaveaHighLimitandLowLimitviolationatthesametimeifthe
sensorviolatesoneofitslimitsand
theencoderviolatestheother.Notethat,inthePeakmodes,
theencodervaluethatiscapturedandevaluatedwithrespecttotheHighandLowLimitsisthe
valuethatcoincideswiththepeakvaluefromthesensor.Theencodervaluethatisevaluatedin