Komatsu 830E Shop Manual page 731

Pressure Failure Detection Circuits
1. When the lubrication cycle is initiated, 24VDC
flows through relay RB6-K4 (8, Figure 3-4) N.C.
contacts to a 1 minute delay timer (7).
2. If the system is operating normally, grease pres-
sure at the rear axle injector bank will rise to
pressure switch (9) setting of 2000 psi (13.8
MPa), closing the switch contacts and energiz-
ing relay RB6-K4 (8), removing 24 volts from
the delay timer. The timer is then reset and no
current will flow from the timer output terminal.
3. If a problem occurs and the system is not able to
attain 2000 psi (13.8 MPa), the delay timer (7)
will energize relay RB6-K2 after 60 seconds,
turning on the ©Low Lube System Pressureª
warning lamp on the overhead display. After
RB6-K2 energizes, it will ground the coil of
RB6-K6 and allow it to energize.
1. Solid State Timer
2. Circuit Breaker 33 (Power Distribution Module in
Cab)
3. Circuit Breaker 35 (Power Distribution Module in
Cab)
4. Pressure Switch (On Grease Pump)
5. Pump Solenoid Valve
6. Relay Board 6, Relay K6
P03022
FIGURE 3-4. ELECTRICAL SCHEMATIC
7. Time Delay Module
8. Relay Board 6, Relay K4
9. Pressure Switch (Rear Axle Injector Bank)
10. Relay Board 6, Relay K2
11. Auto Lube Low Pressure Warning Lamp
12. Relay Board 6, Relay K1
13. Manual Override Switch
Automatic Lubrication System
4. Once RB6-K6 is energized, it will latch and
remain latched as long as the key switch is On.
Also, RB6-K2 will remain energized and the
Low Lube Pressure Warning light will remain on
to notify the operator a problem exists and the
system requires service.
5. The warning circuits are reset when the key
switch is turned Off.
P3-5