4001-4
ELECTRIC CIRCUITS OPERATION EXPLANATION System Chart of Function ITEM
FUNCTION
1
Engine control
2
Work mode selection a) H/S/L mode
METHOD Electronic control (common-rail)
Maximum e ngine speed, p ump cu rrent, and pr essurizing so lenoid v alve ar e co nMachine set ting can be selected ac cordtrolled accor ding to t he sele cted work ing to co nditions su ch as of w orkload o r mode. fuel efficiency preference, and lifting operation. b) Auto-mode Suitable w ork mode is automatically selected.
c) Load prefectch control Pump c urrent is k ept at 0 mA while machine is not being operated.
Selection of auto-mode allows the load to be calcula ted with p ressure of n egative control P1 and P2 which in tur n w ork mode is switched. Pump cu rrent a nd en gine co ntroller ar e controlled by signal from pressure switch.
3
Throttle control
Engine ca n be controlled con tinuously Engine spe ed is adju sted b y cont rol of from idling to high idling speed by opera- throttle valve. tor's instruction.
4
Idling control
Engine sp eed ca n be
switched to/form Pushing knob of switch on the right allows the engine to run idle and pushing it again to return it as it was.
idling by control of onetouch switch.
It makes engine to r un idle while machine Selection of auto-idle allows the engine to is not being operated. run at idling speed automatically in 5 minutes after he lever is sh ifted to its neutral. Shifting lever ma kes t he engine to r eturn to its normal speed automatically. 5
Breaker mode
Pressing t he b reaker ped al allo ws th e Turning ON the pressure switch in breaker engine t o run at t he set spee d a utomati- pilot line allows the engine to run at prevically and boosting pressure will be cut. ously set speed. Als o, pump c urrent will be set as th at in S- mode a nd b oosting pressure is to be cut.
6
Auto preheat
It helps the engine to start easily at a low temperature. Als o, it stabiliz es engine speed immediately af ter st art of the engine to reduce exhausting smoke.
7
Auto warm-up
When coolant temperature is low, it allows In ca se wh ere no op eration of th e the e ngine to st art warming up au tomati- machine after the engine has been started cally after it has been started. is carried out when coolant temperature is low, it automat ically i ncreases engine speed gradually to warm it up.
8
Overheat protection
When engine coola nt t emperature has When coola nt te mperature g oes o ver been incre ased, r educe inject ion quantity 100°C, r educe f uel injection qu antity. to protect engine. Coolant temperature sensor to ECM.
Lep SC4604001-0EN
Depending on co oling w ater t emperature at the time when the key switch is t urned ON, t he g low plug is energized f or a period o f tim e be ing se t. It is to be energized for a ce rtain period of set time after the e ngine h as bee n sta rted t o r educe exhausting smoke.
Issued 03-07