7 - 6 Genie Z-45/22 Part No. 32960Service Manual - Second EditionSection 7 - Repair ProceduresPLATFORM CONTROLS1-2Horsepower Limiter BoardThe horsepower limiter board is responsible forgoverning drive pump output. It reads engine rpmfrom the alternator. The horsepower limiter boardsenses drops in rpm normally due to increaseddrive resistance (rough terrain or incline) anddecreases voltage to the drive controller which inturn decreases voltage to the drive pump therebyreducing pump output to keep the engine fromstalling. Three adjustments are required foroptimum performance.How to Adjust the HorsepowerLimiter BoardThe engine rpm must becorrect before performing thisprocedure. See MaintenanceProcedure B-12,Check andAdjust the Engine RPM.Do not adjust the horsepowerlimiter board unless the staticbattery voltage is above 12V DCand the alternator is operatingproperly with 12.5 to 14.5V DCoutput.Gasoline/LPG models: Performthis procedure in gasoline mode.1 Remove the fasteners from the platform controlbox lid.2 Open the control box lid and locate thehorsepower limiter board.Electrocution hazard. Contact withhot or live circuits may result indeath or serious injury. Removeall rings, watches and otherjewelry.a horsepower limiter board3 Connect the black lead(-) from a DC volt meterto the number 2 terminal, and the red lead(+) tothe number 10 terminal.4 Start the engine from the platform controls.5 Move the engine speed control switch to footswitch activated high idle (rabbit and footswitch symbol).bac12V DC or greatergroundengine rpm sensornot usednot usedlow drive speed limit switchnot usednot usednot usedoutput to drive controllerHorsepower limiter boarda "A" potentiometer-maximum voltageoutput to the controller in the stowedpositionb "B" potentiometer-maximum voltageoutput to the drive controller in theboom elevated positionc "C" potentiometer-reaction rate orhow fast the voltage output reacts tothe change in engine rpma800-610-4101ActionRental.com
