Komatsu PC88MR-10 Shop Manual page 264

10 Structure and function
Electrical control system
Turbocharger protection function
a For the system circuit diagram, see "Engine automatic warm-up function".
This function limits the engine speed to prevent seizure of the turbocharger when the engine speed is
increased suddenly just after the engine is started.
The control time is controlled in accordance with the coolant temperature.
Operating condition
Engine oil pressure: Below 50 kPa {0.51 kg/cm
A: Starting of engine
B: Turbocharger protection time (approximately 0 to 20 seconds)
C: Modulation time (approximately 1.5 second)
D: 500 rpm
E: 1,175 rpm
F: 2,050 rpm (*1)
*1:
Working mode: P mode
Fuel control dial: High idle (MAX) position
Swing lever at full stroke
10-186
(PC88MR-AA90-042-K-00-A)
o
2 } Limits engine speed (see figure below)
Operation
PC88MR-10