Circuit Protection - Fuses - JLG sky trak mmv Service Manual

10.6.1

Circuit Protection - Fuses

a. Auto Type Fuses
The fuse is the most common method used for protecting
wiring circuits. A good fuse (6) will have the center ele-
ment connected to both sides of the fuse. Whenever
there is an excessive amount of current flowing through a
circuit the fusible element will melt (7) and create an open
or incomplete circuit.
6
Fuses are a one time protection device and must be re-
placed each time the circuit is overloaded. To determine
if a fuse is open (7), remove the suspected fuse and ex-
amine the element in the fuse for an open (break). If not
broken, also check for continuity using a DMM or a conti-
nuity tester. If the element is open or continuity is suspect,
replace the fuse with one of equal current rating.
Fuse Types
Current Rating Amperes
Auto Fuses, Mini Fuses
1
2
3
5
7.5
10
15
20
25
30
Maxi Fuses
20
30
40
50
60
Model MMV Rev. 12/04
7
MT0420
Color
Black
Gray
Violet
Tan
Brown
Red
Blue
Yellow
White
Green
Yellow
Light Green
Orange or Amber
Red
Blue
b. Battery Equalizer Fuses
There are two fuses (8) located on the bottom side of the
equalizer (9). These two fuses are 125 amp fuses and are
located on the 12V and 24V positive terminals of the
equalizer. These fuses protect the battery cables con-
nected to the equalizer in case of an internal short or fail-
ure. You will require a small telescoping mirror to check
these two fuses.
As with the auto type fuses, a good fuse (10) will have the
center element connected to both sides of the fuse.
Whenever there is an excessive amount of current flow-
ing through a circuit the fusible element will melt (11) and
create an open or incomplete circuit.
10
Electrical System
9
8
11
MM4290
10.11