User`s guide

Fuses and Protection Circuitry
There is an internal 1A (1 ampere) fast
blow 5mmX20mm fuse for each amplifier
board. If any speaker output contacts the
chassis or any system ground while the
amplifier is powered, a fuse will open up
to protect the amplifier. In this case there
will be noise on the amplifier output and
that channel will not function correctly.
You will need to remove the amplifier
from the system and have the fuse
replaced.
Insure that all signal and power
connections to the amplifier are
removed before opening the chas-
sis. This should be done by a
dealer or experienced technician.
The fuse is changed by opening the top
cover on the chassis using a Phillips type
screwdriver to remove the 6 screws on
the sides of the amplifier that hold the top
cover on. The fuses are located on a
small daughter board near the front of the
amplifier. There is 1 fuse per power
amplifier board. Confirm that the fuse is
blown by inspecting it or measuring the
resistance. Replace the fuse with an
IDENTICAL 1A fast blow 5mmX20mm
fuse. DO NOT CHANGE THIS FUSE
TYPE OR VALUE. Using the wrong fuse
type or value will invalidate your warran-
ty.
No signal current flows through this fuse.
It is used only to protect the amplifier in
case of a short circuit to ground.
The design of the S300i integrated
Amplifier reduces the chance for ground
loop induced hum and noise but we still
recommend that you use shorter intercon-
nect cables to the S300i inputs and con-
nect all power cables to a common outlet
box or power conditioner unit to reduce
the possibility for ground current noise
being induced into the audio signal path.
What to do if there is hum or ground noise
page 10© 2006 bel canto design, Ltd. S300i User’s Guide 0906 Rev. A