3.ELECTRIC AND HYDRAULIC POWER SYSTEM.

3. 1. ARRANGEMENT OF SYSTEM.

Refer to enclosed hydraulic diagram (section D).

A variable displacement hydraulic pump supplies the system.

The oil is distributed to the various electrically operated solenoid valves. When activated these valves supply the oil to the hydraulic cylinders, which power the Jaws, Wire Lift Pin, Guide Pins and Stop Pins.

The pump is connected to accumulators, which are charged as soon as the system reaches maximum working pressure.

As shown in the hydraulic diagram, all the necessary relief valves over centre valves and check valves are fitted to enable the system to function efficiently.

The electric system is powered from 220 or 110 Volt AC and is transformed / rectified to 24 Volt DC.

The system must have a 24 Volt Direct Current emergency power supply.

3.2.FUNCTIONING OF QUICK RELEASE - JAWS ONLY.

Wire or chain held by the Shark Jaw can be released by turning the OPEN-O- LOCK switches to the OPEN position, or by operating the QUICK RELEASE.

When required the QUICK RELEASE system can be used to open the jaws.

QUICK RELEASE is operated by turning both OPEN-O-LOCK switches to the central "0" position and the JAW POSITION ACCEPT lever turned to READY FOR OPERATION. The alarm light goes out and the buzzer comes on when the QUICK RELEASE button cover is opened. Then both QUICK RELEASE buttons must be pressed at the same time.

The need to operate two sets of controls to activate the QUICK RELEASE system is a safety device to prevent the QUICK RELEASE from being operated by accident.

3.3.FUNCTIONING OF EMERGENCY RELEASE

A separate control panel on the bridge operates the EMERGENCY RELEASE.

When the EMERGENCY RELEASE is operated, solenoids nos. 42 and 35 are activated (refer to hydraulic diagram)

The solenoid valve pos. 11 then releases pilot pressure from the accumulators, supplying high pressure oil to the Wire Lift Pin and Guide Pins hydraulic cylinders, to retract WIRE LIFT PIN and GUIDE PINS to deck level before the Jaws open.

Following this, even if the WIRE LIFT PIN or GUIDE PINS do not fully retract for any reason, the Jaws will automatically open and reach deck level in 10 - 20 seconds.

-Pressing the E-STOP button can stop the whole procedure -

3.4.EMERGENCY RELEASE UNDER "DEAD SHIP" CONDITIONS.

The EMERGENCY RELEASE system can also operate under "dead ship" conditions and under load. This is possible because the accumulators are charged at the same time as the jaws are locked and the system reaches maximum working pressure.

Should "dead ship" condition occur and the pump stop the emergency current from the battery makes it possible to release with. power from the accumulators in the same way as described above. Even under "dead ship" condition, with no power from the pump, a load can safely be held in the Jaws, as the link joints are "locked" past 180 degrees.