Nilfisk-Advance Warrior ST Service Manual

Also see for Warrior AXP: Service manual Instructions for use Sevice manual

Contents

Scrub System, Disc 58Service Manual – Warrior ST, AXP, EcoFlexScrub System, DiscFunctional DescriptionThe scrub system consists of a motorized scrub deck that is raised and lowered with a lift actuator. The twocounter rotating brushes are driven by independent motors with integral speed reduction gear boxes.Brush MotorsUnlike most other motors in the Warrior system, the Brush motors are not PWM speed controlled, but areeither full-on, full-off, or a special shunt-brake function to remove the brushes. The primary on/off functionis controlled with the brush motor contactor (K1) located in the main electrical panel in front of the operatorcontrols This is a special motor contactor that also includes a set of normally closed contacts that are usedfor the “Brush Remove” function. This is a Single-Pole, Double-Throw (SPDT) relay. (A motor contactor isa name used for a relay that has high-power handling contacts necessary for the high amperage of a motorcircuit.)During normal operation, the brush remove relay (KBR) is not activeand its contacts are normally open. When the scrub motor is turnedoff, it coasts to a stopWhen the brush remove function is active, the KBR relay closes,which connects to ground. When the scrub motor is turned off, bothof its inputs are connected to ground. This is a short-circuit of themotor windings, which acts as a magnetic brake, bringing the motorto a stop very quickly. (An intentional short-circuit is called a shunt,so this is referred to as shunt-braking.) This rapid deceleration of thebrushes causes them to spin off the brush platesThe Warrior controller measures the current through the motorsby examining the voltage drop across the ground wire between thebattery and the motor. (Wires are not perfect conductors, and willhave a voltage drop.) This allows the controller to know how muchscrub pressure is being appliedScrub Deck,Disc TypeLiftAccuatorBrush MotorContactorScrub DeckHousingBrush MotorGear BoxBrush PlateBrushK1(SPDT)KBR(SPST)Bat+ScrubMotorBat+Bat+ScrubMotorBrushRemoveBrush Run