CASE 1288 1288LC 1288CK 1488 Crawler Excavator SCHEMATIC Service Manual

HYDRAULICS EXCA HYDRAULICS EXCA V V A A TORS TORS " " 1 1 2 2 8 8 8 8 & & 1 1 4 4 8 8 8 8 C C " " 08 - 1998 English version Reproduction , réimpression et traduction, même partielles sont interdites sans une autorisation spéciale de nos services Centre de formation

1-1 CASE Issued 11-97 Printed in England Mon 1288/1488 GB Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS CONTENTS PAGE STARTING ASSISTANCE ........................................................................................1.02.00 ELECTRIC ACCELERATION ....................................................................................1.04.00 AUTOMATIC RETURN TO IDLE ..............................................................................1.05.00 ENGINE OVERHEATING SAFETY DEVICE ............................................................1.06.00 SPEED-SENSING SYSTEM ..................................................................................1.07.00 SWING BREAK RELEASE ......................................................................................1.08.00 SWING BREAK ........................................................................................................1.09.00 AUTOMATIC TRAVEL SEQUENCES FOR TWO-SPEED EXCAVATORS ..........................................................................1.12.00

Servo-motor on the injection pump goes to ECO mode and then comes back to Master switch Starts Temp sensor on engine block Ignition key Buzzer sounds Automatic stop t = 2 s If does not start - Safety indicator lamps light up - The hydraulic filter and air filter indicator lamps go out - Buzzer sounds again - Use push-button to stop After 30 sec. Manual push-button shut-down Engine speed 1200 r.p.m. Water temp lower than 60¡ C PRE-HEATING LED on control box flashes Servo-motor Electronic control housing Engine speed 1200 r.p.m. Temp sender on engine block Engine speed 1200 r.p.m. Water temp higher than 60¡ C Time with engine speed at 1200 r.p.m. over 5 mn. PRE-HEATING LED on control box goes out Servo-motor Electronic control box Select desired engine speed Time with engine speed 1200 r.p.m. less than 5 mn STARTING ASSISTANCE Mon 1288/1488 GB Issued 11-97 Printed in England 1 -2 CASE Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS

PURPOSE: When the engine is switched on, the system provides: - A pre-opening of the injection pump - Automatic return of injection pump to the high idle position. WORKING PRINCIPLES - When the system is switched on using the ignition key, the buzzer sounds. The buzzer stops automatically after two seconds. - If the engine does not start, the following warning lamps come on: battery charge, engine oil pressure, minimum pilot pressure, air filter and oil filter restriction warning. After 30 seconds, the last two warning lamps go out and the buzzer sounds (the buzzer can be turned off by the push-button on the instrument panel) - If the engine starts, the injection pump servo-motor, which is in ECO MODE speed position, cuts in to provide an engine speed of 1200 rpm (high idle).. - if the engine coolant water temperature is lower than 60¡C or if the time that the motor runs at 1200 rpm is less than 5 minutes, the electronic system will not permit changing to the LOW, FINE, ECO or MAX modes. This is indicated by the PRE-HEATING indicator which has a flashing indicator lamp (LED). STOP 1-3 CASE Issued 11-97 Printed in England Mon 1288/1488 GB Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS HEATING PRE FINE ECO MAXI 1 TRAVEL 2 IDLE LOW IDLE AUTO HEATING PRE Location of PRE-HEATING indicator lamp Location of buzzer stop push-button ASSISTANCE FOR STARTING

950 r.p.m. Control box Servo-motor Engine speed depending mode selected LOW IDLE 1200 r.p.m. AUTO IDLE 1600 r.p.m. FINE ECO 2270 r.p.m. MAX Electronic control box 1950 tr/mn 1850 tr/mn 1 1 2 2 8 8 8 8 1 1 4 4 8 8 8 8 Mon 1288/1488 GB Issued 11-97 Printed in England 1 -4 CASE Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS FINE ECO MAXI 1 TRAVEL 2 IDLE LOW IDLE AUTO HEATING PRE ELECTRIC ACCELERATION (AFTER ASSISTANCE WITH STARTING) PURPOSE To set the correct engine speed in accordance with the MODE selection made by the operator. It provides the following : • 2 idle modes - LOW IDLE is the low idle speed at 950 rpm. - High idle (1200 rpm) cannot be selected and is only obtained automatically during assistance with starting when selecting AUTO-IDLE function (see page 1.5.00) • 3 work modes - FINE: 1600 rpm for low output work, and for handling - ECO: 1850 (1288) or 1950 (1488) rpm, economical digging is possible - MAX: 2240 rpm, maximum power, hard work The mode is selected at the control box which informs the electronic control box. This sends a signal to the servo-motor which is directly connected to the injection pump lever. In this way engine speed is obtained in accordance with the selected mode.

1-5 CASE Issued 11-97 Printed in England Mon 1288/1488 GB Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS - Swing and travel pressure switches not actived - Pressure sensor on LS circuit with P under 40 bar t = 5 sec. Electronic control box AUTO IDLE on control box Servo motor Injection pump 1200 r.p.m. Electronic control box Servo-motor Injection pump Engine speed as per mode selected at beginning Pressure sensor on LS circuit with P over 50 bar - Swing pilot pressure switche - Travel pilot pressure switche AUTOMATIC RETURN TO IDLE (AUTO-IDLE MODE) PURPOSE Sets engine speed to idle when none of the various controls for excavator functions are activated. This applies whichever mode has been selected (FINE, ECO or MAX) WORKING PRINCIPLES - The indicator lamp on the push-button lights up when the AUTO-IDLE mode is pressed to obtain automatic return to idle. - On condition that no movement occurs at the control levers or pedals, also that the swing and travel pressure switches show no action and that the LOAD SENSING information line is at a pressure lower than 40 bar, all this for a period of 5 seconds. - When these conditions are met, the electronic control box informs the injection pump servo-motor and the AUTO-IDLE mode (idling at 1200 rpm) is obtained. The indicator lamp lights up on the push-button for the mode selected.- When one or more of the controls is operated again, the engine returns to the speed of the mode which was previously selected (FINE, ECO or MAX). This is because information is given to the control box in the following manner: For attachment and options functions - When the L-S information pressure sensor detects a pressure greater than 50 bar For the swing function - When the pilot pressure switch receives a pressure information For the travel function - When the release pressure switch receives a pressure information - In this case, the indicator lamp on the push-button stays on continuously.

Mon 1288/1488 GB Issued 11-97 Printed in England 1 -6 CASE Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS FINE or LOW IDLE MODES MODES MAXI or ECO Buzzer sounds instrument panel Temp sensor on engine block Water temp over 115° C Servo-moteur Electronic control box Push- button to stop the LED ligts up STOP Indicator lamp lights up 110° MODE FINE MODE unchanged Water temp lower 100° C Return to selected Mode PURPOSE Safeguards the engine as regards temperature WORKING PRINCIPLES - If the engine coolant solution reaches a temperature in excess of 115° C, the sensor on the engine block gives information to the instrument panel - The buzzer sounds (stopped by push-button) - The stop warning lamp located at top left of instrument panel lights up. - The engine temperature gauge needle is at the beginning of the 2nd red mark. - The engine temperature gauge LED lights up. - If the engine is in ECO or MAX, the information is transmitted to the electronic control box which reduces the engine speed to the FINE mode and the “FINE” LED lights up. - If the engine is in FINE or LOW IDLE, there is no change - At 100° C, the various modes: FINE, ECO or MAX can again be selected. ENGINE OVERHEATING SAFETY SYSTEM

1-7 CASE Issued 11-97 Printed in England Mon 1288/1488 GB Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS P 35 Proportional valve Pump power (p x qv) Torque regulator valve Engine speed Sensor on engine (flywheel teeth) Electronic control box “SPEED-SENSING” SYSTEM PURPOSE It maintains power balance between the available engine power and the demands of the hydraulic system, regardless of engine speed selected. WORKING PRINCIPLES - A sensor located on the teeth of the engine flywheel, detects engine speed and transmits it to the electronic control box. - If the hydraulic power which has been consumed causes engine speed to fall, electric information coming from the electronic control box acts on a hydraulic proportional valve, fed by pressure from the hydraulic assistance circuit. - Depending on the intensity of the signal received, which depends itself on the engine speed, this valve delivers a pilot pressure which acts on the torque regulator valve of the hydraulic pump, to reduce the flow supplied by the pump so that the hydraulic power consumed is in line with engine speed (depending on mode selected)

Mon 1288/1488 GB Issued 11-97 Printed in England 1 -8 CASE Training Center BASIC PRINCIPLES OF ELECTRONICALLY ASSISTED SYSTEMS P 35 Brake release Electronic control box Control lever Pressure selector Pressure switch solenoid valve If counter- rotating PURPOSE - Enables the upperstructure swing hydraulic motor brake release to take place WORKING PRINCIPLES - When the control lever is tilted, the pilot pressure actuates a pressure selector. The pressure selector closes a pressure switch which informs the electronic control box - This in turn activates a solenoid valve, fed by the hydraulic assistance circuit pressure. This pressure arrives at the hydraulic motor brake and releases the brake. - Since the hydraulic motor is being fed it drives the upperstructure round by means of a reduction gear - When the operator swings in the opposite direction, without stopping at the control lever neutral position, the pressure selector is pressed onto the other side and the pressure switch informs the electronic control box, which maintains the swing brake in the released position. UPPERSTRUCTURE SWING BRAKE RELEASE

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CASE 1288 1288LC 1288CK 1488 Crawler Excavator SCHEMATIC Service Manual

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