Mack V-MAC IV - Electrical Accessory Connection Points; Battery Post (BATT); Ignition Post (IGN); Ground Post (GND)

V-MACCo-PilotOperator'sManual71
ELECTRICALACCESSORYCONNECTIONPOINTS
ThisMACKchassisiselectricallyreadyforconvenientinstallationofelectrical
accessories.Usethedesignatedbatterypost(+12V),groundpost,CBjack,buffered
RPMoutputs,bufferedmi/houtputs,andtheSAE/A TAJ-1708postlocatedonthe
electricalequipmentpanelfortheinstallationofanyelectricalaccessories.Each
connectionpointisdescribedbelow.
BatteryPost(BATT)
Thisisa+12volt,unswitchedbatterypowerconnection.Itcanbeusedtopower
externaldevicesthatrequirepoweratalltimes,evenwhentheignitionkeyisturned
OFF.Thissourceisprotectedbya15-ampcircuitbreaker.
IgnitionPost(IGN)
Thisisa+12volt,switchedbatterypowerconnection.Itcanbeusedtopower
externaldevicesthatrequirepoweronlywhentheignitionkeyisON.Thissourceis
protectedbya15-ampcircuitbreaker.
GroundPost(GND)
Thisisagroundconnection.Itcanbeusedasapowerreturn(−)connectionfor
externaldevices.
RPMOutput
Thisisa50%dutycycle,5-volttransistor-transistorlogic(TTL)compatible,
square-wavesignalthatiscalibratedtoprovideastandardpulserateof12pulses
perenginerevolution.
Note:Transistor-transistorlogiccompatibleofthisoutputmaybeaffectedbyother
devicesconnectedtothisoutput.MaximumratedcurrentoftheTTLoutputis10
mA.Totalcurrentdrawofalldevicesconnectedtothisoutputmustnotexceed10
mAat4volts.
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