Komatsu PC200-8M0, Shop Manual, Page: 281 / 1254

SEN06123-00
PC200, 200LC, 220, 220LC-8M0 10-600
15
600 Electrical system
Electrical control system
Function
q
This function allows the operator to select
engine torque (T) and pump absorption torque
d e p e n d in g o n t h e w o r k c o n t e n ts o f t h e
machine.
Five modes of P, E, L, ATT, and B (three
modes of P, E, and L for machines with “No
ATT” specified) are specified as working
modes.
To select a working mode, use the working
mode selector switch of the machine monitor.
q
The pump controller controls the pump so that
it can absorb all the torque at the output points
of the engine depending on the pump absorp-
tion torque specified for each mode, rotation
set by the fuel control dial, and actual engine
speed.
1) Control method in each mode
P mode, E mode, and ATT mode
q
Matching point:
q In P, E, or ATT mode, engine speed is always
controlled so that it is kept around the match-
ing point specified for each mode.
q If the pump load increases and the pressure
rises, engine speed (N) lowers. If it happens,
the engine speed is increased to around the
matching point, allowing the pump controller to
decrease pump discharge (Q). On the con-
trary, the pump load decreases and the pres-
sure lowers, the pump controller continues to
increase pump discharge until the engine
speed reaches around the matching point.
Mode Matching point
P and ATT (Work)
99.2 kW/1,800 rpm
{135 HP/1,800 rpm}
E
86.8 kW/1,800 rpm
{118 HP/1,800 rpm}