Toro Groundsmaster 4500-D Series - Page 144

ForwardDirectionFanOperation(continued)
REVERSE
FROM GEAR
TO OIL
TO RESERVOIR
TO LIFT/LOWER
CIRCUIT
TO STEERING
CIRCUIT
PUMP SECTION
FROM GEAR
PUMP SECTION
DIRECTION
T
PRV
S1
CV
FD
P2P1
ST
L
M1 M2
50/50 FLOW
DIVIDER
FAN CONTROL
MANIFOLD
G2
G1
COOLER
g308210
Figure58
ReverseDirectionFanOperation(Figure58)
TheTECcontroller(T1)canreversethecoolingfantocleandebrisfromtherear
intakescreen.Ifhydraulicoiland/orenginecoolanttemperaturesincreaseto
anunsuitablelevelorifamanualfanreversalisrequestedviatheInfoCenter
display,ahighPWMsignalissenttothePRVvalvetoslowthecoolingfanand
directpumpoilowawayfromthefanmotor.Thecontrollerthenenergizes
solenoidvalveS1inthefancontrolmanifoldtoreversecoolingfanmotoroilow
sothatthemotorrunsinthereversedirection.AlowerPWMsignalissenttothe
PRVvalveallowingoilowtoreturntothefanmotorbutinthereversedirection
causingthemotorandcoolingfantoruninreverseforashorttime.
Note:Thefanreversalprocessisdesignedtocleandebrisfromtherear
screenbutnottheradiator.RefertoOperator’sManualforradiatorcleaning
maintenancerecommendations.
HydraulicSystem:HydraulicFlowDiagrams
Page5–42
Groundsmaster
®
4500-D/4700-D
19245SLRevA