Sonodyne SBA 250P - Manual (Page 14)

Page 12
SMA/ SBA SERIES
MAINTAINANCE
Only competent or qualified persons should attempt any service or maintenance of your amplifier.
Your new SMA/SBA Series amplifiers will need minimal maintenance. No internal adjustments need to be
made to the unit to maintain optimum performance. To provide years of unhindered operation we suggest a
maintenance inspection be carried out on a regular basis, say every 12 months or so.
FANS
Due to the openness of the air path through your SMA/SBA Series amplifier, very little dust should settle
within the amplifier. The unit has been designed so that any dust and/or foreign particles that do settle
within the amplifier will not unduly hinder the cooling of the amplifier.
The grille in front of the fans will act to limit the amount of dust and lint entering the amplifier. You will find
in time that there will be a build up of dust and lint on the grille and foam that may start to hinder the
airflow through the amplifier. You should periodically remove the dust and keep the grille clean. Removal of
dust from the rear grille will also aid cooling.
Over time, dust may build up on the leading edge of the fan blades and reduce their cooling efficiency. The
time taken for this to happen will depend on the environment and the amount of use.
The fan blades are accessible once the lids are removed and can be easily cleaned. You need only hold the
fan rotor still and wipe the dust off the blades. Many users stall the fan and use compressed air to blow the
dust off the fan blades. It is important to note that the fan blades must be held still whilst blowing air over
the blades otherwise you may burn out the bearings in the fan.
FUSES
There are two (2) rail fuses 6.3A Slow Blow, 20x5mm size provided internally in the unit. These rail fuses
are in series with the positive and negative DC supply to each amplifier channel and provide overall
protection for the output stage. If the amplifier is subjected to heavy use such as short circuits, over loads,
these fuses will eventually fatigue and may require replacing to ensure they do not fail at an inconvenient
time.
WARNING: Make sure the unit is off and is unplugged from the mains. Give the main filter capacitors time
to discharge before removing lids and inspecting the fuses.
You should replace the fuse if the element is sagging or discoloured. Only ever replace with the same type
fuse and current rating.
When checking for a failed fuse, do not rely on visual inspection alone. You should use an ohm meter to
check continuity.