Electro-Voice 7300A - ELECTRICAL; 120 Vac, 50;60 Hz Power Connections; 220;240 V ac, 50;60 Hz Power Connections

Operating and Service Instructions for the Electro-Voice 7300A Power Amplifier
(BOTH SIDES)
1 ELECTRICAL
Two amplifier models are
available. One model hats a 50/60
Hz power transformer with two
120 V ac primary windings. These
windings may be wired in parallel
or series for operation at either
120 V ac or 220/240 V ac. The ot¬
her amplifier model is for export
into countries where the ac line
voltage is 100 volts, 50/60 Hz. The
next two sections refer to the first
model with the dual 120 V ac pri¬
mary windings.
1.1 120 V ac, 50/60 Hz
Power Connections
The amplifier is provided
with the primary of the power
transformer strapped for 120 V ac
operation from the factory. Refer
to Figure 2a for the wiring details.
WARNING! Verify that the power
transformer's primary circuit
configuration is correct for the
intended ac line voltage BEFORE
applying power to the amplifier.
1.2 220/240 V ac, 50/60 Hz
Power Connections
The power transformer
has two 120 volt primary windings
which can be connected in parallel
for 120 V ac line voltages, or in
series to meet 220/240 V ac re¬
quirements. Use the following
procedures to re-strap the primary
of the power transformer for
220/240 V ac applications.
1. Make sure the amplifier is
not connected to 2 iny pow¬
er source.
2. Remove and save the
eleven screws securing the
top cover. There are three
screws on each side and
three along the top-rear
edge of the chassis. In
addition, you must remove
the two inside screws al¬
ong the top edge of the
front panel. Refer to Fig¬
ure 1 for the exact screw
Figure 1 Top Cover Removal
locations.
3. Locate terminal blocks
TBl and TB2 located on
the side of the chassis
near the rear input PC
board. Reconnect the
leads as shown in Figure
2b.
4. Install the top cover with
the eleven screws previou¬
sly removed. Two screws
are longer than the others
removed from the sides
and rear. These longer
screws install into the
rearmost position on each
side of the chassis.
5. Install the 5A fuse,
Littelfuse Type SAB 5A
/250V slo-blo 326-series
ceramic body or equiv¬
alent.
2 INSTALLATION
2.1 Rack Mounting
The amplifier may be
installed in a standard 19 inch
equipment rack. It requires bVi
inches of vertical rack space and
secures to the rack cabinet with
the four rack mount screws and
cup washers provided in the hard¬
ware kit.
2.2 Ventilation
The amplifier must be
adequately ventilated to avoid
excessive temperature rise. It
should not be used in areas where
the ambient temperature exceeds
60 °C (140 °F). To determine the
ambient air temperature, operate
the system in the rack until the
temperature stabilizes. Measure
the ambient air with a bulb-type
thermometer held at the bottom
of the uppermost amplifier. Do
Electro-Voice ® a Mark W Company
1