Ok To Lower Circuit; Electric Clutch Circuit - Toro ProCore 648 Service Manual

Electric Clutch Circuit (Fig. 3)
The electric clutch circuit is used on the ProCore to pro-
vide current for the electric clutch which rotates the cor-
ing crankshaft. This circuit is composed of the aeration
#3 proximity switch, the clutch relay, the electric clutch
and diode D3. The electric clutch circuit relies on the op-
eration of the "OK to lower" circuit for completing the
clutch circuit (See OK to Lower Circuit in this section).
Electric clutch circuit protection is provided by fuse F2.
Not Aerating (Clutch not Engaged)
Whenever the coring head is in the raised position, the
aeration #3 proximity switch is open and the clutch relay
is not energized. The electric clutch will not be energized
so rotation of the coring crankshaft does not occur.
TO IGNITION
SWITCH
TERMINAL "L"
TO IGNITION
SWITCH
TERMINAL "L"
Electrical System
NOT AERATING (CLUTCH NOT ENGAGED)
GROUND
(NOT ENERGIZED)
AERATING (CLUTCH ENGAGED)
GROUND
(ENERGIZED)
Aerating (Clutch Engaged)
The clutch relay will be energized as the coring head is
lowered to the point when the aeration #3 proximity
switch closes. This closed proximity switch provides a
complete circuit if the "OK to lower" circuit is closed.
Once the clutch relay is energized, current is provided
to the clutch and rotation of the coring crankshaft be-
gins.
The clutch will continue to be energized until either:
A. The coring head is raised which opens the aera -
tion #3 proximity switch.
B. The "OK to lower" circuit opens (e.g. the operator
releases the traction lever while aerating).
(ENERGIZED)
(HEAD LOWERED)
Figure 3
Page 5 – 6
TO
OK TO LOWER
CIRCUIT
(NOT ENERGIZED)
TO
OK TO LOWER
CIRCUIT
(ENERGIZED)
CONTROL CURRENT
CLUTCH CURRENT
ProCore 648