Fuses; Power Circuit Fuses; Control Circuit Fuses; Hydraulic Power Unit - JLG TOUCAN DUO Service Manual

III-20

3.21 Fuses

The fuses used in the work platform electrical system
protect the electric circuit and the electronic cards
from an excess current (inside the electrical circuit in
which they are used).

3.21.1 Power circuit fuses

- Fuse 63 A (F1) : It is located on the chassis
above the speed controllers. It protects the
entire electrical circuit of the machine.
- Fuse 16 A (F3) : It is located on the chassis
next to the mast hydraulic power unit. It
protects the supply circuit to the electrical
cylinder and to the shelf elevation power unit.

3.21.2 Control circuit fuses

- Quick acting fuse 5 A (F2) : It is installed on
the face of the emergency control panel. It
protects the entire control circuit.
- Quick acting fuse 500 mA (F4) : fuse
present only if the battery cut out and
hourmeter option is installed. It is fitted on
the emergency control panel face. It protects
the discharge indicator and the hourmeter.
DANGER
Ensure the charger plug and the battery cables
are disconnected before any maintenance on
a fuse. Failure to do so may result in death or
serious injuries.
30
GENERAL

3.22 Hydraulic power unit

An independent power unit consisting of a pump
section and driven by a 24 VDC motor is installed on
the chassis, behind the mast. The power unit supplies
the hydraulic power to activate the elevation function
of the machine.

3.22.1 General maintenance

Gear type hydraulic pumps can be relied on to deliver
reliable performance over a long period of time if
operating in a properly maintained system. This
includes using clean oil of the correct grade, regular
filter cleaning and frequent inspections of the system
components. However if a pump fails, it is important
to determine all the causes and to eliminate them to
prevent repeated failures.
There are several causes for gear pump failure. The
following are the most common causes of pump
failures.
1. Abrasive wear caused by fine particles.
Abrasive wear caused by fine particles is the most
frequent cause of pump failure. Its symptom is usually
a gradual decrease in power and speed of the hydraulic
system. Fine particles or other foreign bodies
circulating through the system cause wear on all
components and is noticeable on pressure plates,
housing bores and in the shaft bearing area.
Dirt can enter the system through worn seals,
especially on dirty equipment. Always clean tank caps,
funnels and other areas around the filler neck before
opening the tank. Immediately cover all disconnected
lines, fitting and various openings.
The fine particles that cause abrasive wear are usually
not visible to the eye : The size of these particles is
about 125 microns. Oil containing particles of this
size can actually look clean while having enough
abrasive particles to cause failure. A dull sandblasted
area may appear near the face of the gear. This is
caused by contaminated oil flowing through the
lubrication grooves.
TOUCAN Duo
Updated 06-2015
III-20
models