Kubota WSM J Series Workshop Manual page 19

J SERIES, WSM
For D1005 and V1305
1. Circuitry desigh
The Emergency Relay-20 (EG-20) circuitry consists of the following circuits:delay timer (6) that serves to delay
detection until the oil temperature rises; sensor circuit that senses an oil pressure, water temperature or battery
charge error and holds the error status; emergency stop circuit that deactivates the delay timer (1) and lock-in
circuits and forces the drive circuit to turn on.
2. Circuitry details
- Delay timer circuit
The delay timer circuit provides for a delay from the instant the starter is released to the instant the sensors get
started. The delay timer (1) is activated by the voltage at the No.50 terminal of the key switch (1).
- Sensor circuit (7)
This circuit serves to sense the oil switch (4), water temperature switch (5) and alternator L terminal (3). If any of
the 3 elements gets grounded for 4 ms or longer, the sensor circuit (7) is activated to hold this status and send
a signal to the drive circuit (10).
- Emergency stop circuit (8)
This circuit is used to deactivate the delay timer (6) and force the engine to a stop. The drive circuit (10) is also
activated by grounding this terminal.
- Drive circuit (10)
This circuit is used to drive the built-in relay (9) that turns on the non-energized-at the stop solenoid (11). The
drive circuit (10) consists of relay drive transistor, feedback diodes, etc.
3. Circuit behavior
For a certain time after the key switch (1) has been set to the start position (50) to get the engine started, the oil
pressure, water temperature and battery charge status are not detected for an error and an emergency stop.
When the key switch (1) has been returned from the start to ON position (AC terminal active), the EG-20 circuitry
gets ready for error detection after a specified delay time.
If the key switch (1) is placed to the OFF position or any of the water temperature switch (5), oil switch (4) and
battery charge switch is detected, the drive circuit (10) is activated to turn off the current of stop solenoid (11).
If the emergency stop switch is short-circuited, the current of stop solenoid (11) is also cut off.
(1) Key Switch
(2) Battery
(3) Alternator L Terminal
(4) Oil Switch
(5) Water Temperature Switch
(6) Delay Timer
(7) Sensor Circuit
(8) Emergency Stop Circuit
(9) Built-in Relay
(10) Drive circuit
(11) Stop Solenoid
M-6
GENERATOR
W10138290
KiSC issued 10, 2016 A