Nilfisk-Advance CS7000 Fuel Cell EcoFlex, Service Manual

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301 Service Manual – CS7000 301
Scrub System
Functional Description
Overview
The scrub system includes the scrub brushes, scrub brush motors, side squeegees, and the scrub deck
actuator which lowers and raises the scrub deck.
The scrub deck actuator lowers the scrub brushes any time the scrub system is enabled. The brush motors
switch on when the drive pedal is moved from the neutral position. The operator can enable the scrub system
independent of the solution and recovery systems to scrub without adding or picking up solution.
Scrub Pressure Control
The electric scrub deck actuator motor (
M11
) moves the scrub deck up and down to control the scrub
pressure. The retract limit switch (proximity sensor) (
S1
) stops the upward deck movement at the upper
travel limit.
The brush current sensor (
B1
) acts like an “amp clamp” around the brush motor wires to constantly measure
the total current draw of all three brush motors. This current reading is sent to the A1 Main Machine
Controller on pin J7-27 Brush Current Sense. The A1 Main Machine Controller interprets this current value
and raises or lowers the scrub deck as follows:
• If the brush motor current drops below the preset limits for the selected scrub pressure (1-3), the scrub
deck actuator will lower the scrub deck to increase the scrub pressure and current draw until the current
draw is again within the correct range.
• If the brush motor current rises above the preset limit for the selected scrub pressure, the scrub deck
actuator will raise the scrub deck to decrease the scrub pressure and current draw until the current draw
is again within the correct range.
The scrub brush current monitoring and scrub deck actuator allow the machine to automatically compensate
for a variety of floor surfaces and scrubbing conditions while maintaining constant scrubbing pressure.
If the scrub deck actuator is unable to maintain the combined brush motor current draw below 75 amps for
25 seconds, or if there is a short circuit, the A1 Main Machine Controller will set an over-current fault code.