Scrub System, Disc 124Service Manual – SC6500
™
Circuit Description
The coil sides of contactors K2, K3 and K4 get positive voltage from the Battery when the load side of contactor
K5 is closed. Contactor K5 closes when the A2 Control Board Assembly connects the K5 coil to battery ground.
Contactors K2, K3 and K4 are connected to battery ground through the A2 Control Board Assembly.
The Right Brush Motor M9, Center Brush Motor M10 and Left Brush Motor M11 get positive voltage from the
Battery when the load sides of contactors K2, K3 and K4 are closed respectively. Contactors K2, K3 and K4 close
when the A2 Control Board Assembly connects the K2, K3 and K4 coils to battery ground. The Right Brush Motor
M9
, Center Brush Motor M10 and Left Brush Motor M11 are connected directly to battery ground.
The Brush Actuator M2 gets voltage from the A2 Control Board Assembly which switches the polarity to move
the scrub deck up or down. When the A2 Control Board Assembly receives a signal from the A3 Switch/Display
Panel Assembly
via the CAN BUS that the operator has pressed the scrub on switch, the A2 Control Board
Assembly
sends the appropriate voltage to the Brush Actuator M2 to lower the scrub deck to the operating
position.
The Scrub Deck Sensing Resistor R2 senses the deck size so the operator does not need to program the deck
size into the hidden menu.
As the brush motor current passes through the BRN current sense wire, which is in effect a low-value
resistor, a small voltage drop is developed across it which is proportional to the motor current. This voltage
change is inputted to pin J2-2 on the A2 Control Board Assembly. Any surrounding temperature change in
the BRN current sense wire affects its resistance, so the temperature is sensed by a thermistor built into
the A2 Control Board Assembly. This allows error correction for the temperature resistance changes in the
BRN current sense wire. When A2 Control Board Assembly senses a current draw out of the desired range it
automatically turns on the M2 actuator motor to raise or lower the scrub deck. This process is ongoing in
maintaining the operator’s selected scrub motor current load setting to sustain the desired brush working
pressure.
To Next Page
Loading...
Need help?
General
