Zoomlion ZT20J, Service And Maintenance Manual

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a) Ground the hood and weld it in any area other than the turntable.
b) Ground the turntable and weld it in any area other than the turntable.
c) Ground the platform/support and weld it in any area other than the platform/support.
d) Ground a specific boom section and weld it in any area other than the specific boom section.
e) Place pins, wear pads, wire ropes, bearings, gears, seals, valves, electrical wiring or tubing
between the grounded location and the weld zone.
Violation of the above requirements may result in damage to components (such as electronic module,
rotating bearing, collector ring, etc.).
3.7 Use Insulating Grease in Electrical Connection Locations
Insulating silicone grease should be used for all electrical connections for the following reasons:
Prevent the mechanical joint between the male and female pins from being oxidized.
Prevent electrical failure caused by too low conductivity between pins when wet. Follow the steps
below to use insulating grease for electrical connectors. This procedure applies to all plug connections
installed outside the distribution box. Silicone grease is not suitable for use with externally sealed
connectors.
a) The silicone grease should be placed around the male and female pins on the inside of the
connector before assembly to prevent oxidation. It can be operated with a syringe for convenience.
Note: oxidation for a certain period of time will increase the resistance of the connector and
eventually cause a circuit failure.
b) Each wire that exposes the connector housing should be wrapped with silicone grease to prevent
short circuits. In addition, silicone grease should also be used at the joint where the male and
female plugs are connected to each other. Other joints (such as around the buckle) that may cause
the connector to enter the water should also be sealed.
Note: since the conductivity of the cleaning fluid is stronger than that of water, it is particularly
prone to occur when the machine is cleaned by pressure cleaning.
c) Battery boxes and battery chargers should be sealed with silicone grease.
Note: coagulating sealants can also be used to prevent short circuits and are relatively clean, but will be
more difficult to handle later when removing the pins.
3.8 Engine Electrical System Maintenance
The engine electrical system integrates a computer and microprocessor to control engine ignition, fuel
control, and emissions. Since the computer is very sensitive to good electrical connections, the electrical