Power Line Fuse; Towfish Fuse - Klein 3900 Series Operation And Maintenance Manual

3-4
CHAPTER 3 Preparation for Use
After checking the power source, and modifying the power cord if required,
connect the TPU to AC power.
3.3.2
The main AC power input line is protected by two 2-A, 5 x 20-mm slow-blow
fuses rated for 250 volts (P/N 13000045). These fuses are located on the rear
connector panel above the power cord receptacle. Before changing the fuse, be
sure that the TPU is disconnected from its power source. To remove the fuse, lift
the tab and pull out the fuse insert. A spare fuse should also be located there.
problem that must be corrected before attempting further operation.
3.3.3
The towfish is protected by a 6.3-A, 5 x 20-mm slow blow fuse rated for 250 volts
(P/N 13000163). It is located on the back panel of the TPU and is below the
TOWFISH connector. Before changing the fuse, be sure that the TPU is
disconnected from its power source. To remove the fuse, use a flat bladed
screwdriver to push in and then turn the fuse receptacle counterclockwise. The
fuse will pop out. Remove the fuse from the holder to check or change it. When
replacing it, there are two tabs that line up in the insert. When the tabs are aligned,
push in on it and turn it clockwise to lock it into position.
Series 3900 Sonar System Operations and Maintenance Manual
Table 3-1:
COLOR
Yellow/green
Blue
Brown

Power Line Fuse

CAUTION Do not replace a fuse with one with a higher current rating. Do
not bypass the fuse. Failure to observe this caution may cause damage to
the equipment and void the warranty. If fuses blow repeatedly, there is a

Towfish Fuse

TPU Power Cord Wiring
FUNCTION
Ground (earth)
Neutral
Hot
11214510, Rev. 02