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Com-Tech Power Amplifiers
Reference Manual
fuses and high-frequency drivers are protected by high-
speed instrument fuses.
Depending on the application, you may want to use a
PIP module to protect your loudspeakers. When prop-
erly configured, all PIP modules with signal-driven com-
pression can provide loudspeaker protection. Some of
the PIP modules with signal-driven compression in-
clude the
P.I.P.-AMCb, P.I.P.-EDCb and P.I.P.-PA. While
the P.I.P.-EDCb is most commonly used for general
loudspeaker protection, the P.I.P.-AMCb is very popular
in systems that require a high-quality crossover, and the
P.I.P.-PA is the processor of choice for applications that
require a microphone and line level input for each chan-
nel. For more information on PIP modules, see Section
8.
3.4 AC Power Requirements
All 120 VAC, 60 Hz North American units have a NEMA
5-15 AC plug with an integral voltage presence lamp.
These units include a 16 gauge cord with Com-Tech
210s and 410s, and a 14 gauge cord with Com-Tech
810s and 1610s. Other Com-Tech amplifiers are fur-
nished with an appropriate AC cord and plug. All Com-
Tech
“10” Series amplifiers utilize a convenient, 3-foot-
long power cord.
To meet full regulatory system com-
pliance, these cords must be plugged into a local,
cabinet mounted, commercial grade electrical out-
let box. “Extension” cords are not recommended or
adequate.
Use an isolated wall outlet whenever possible with the
correct voltage and adequate current. Voltages greater
than 10% above the specified AC mains voltage for the
amplifier may damage the ±15 volt regulator, filter ca-
pacitors and output transistors. See Section 7 for power
requirements under various conditions.
All specifications in this manual were measured using
120 VAC, 60 Hz power unless otherwise noted. Specifi-
cations are derived using a mains voltage that is accu-
rate to within 0.5% with THD less than 1.0% under all
testing conditions. Performance variations can occur at
other AC voltages and line frequencies. In addition, line
regulation problems will directly affect the output power
available from the amplifier.
“Soft-Start”
inrush current limiting, protects the house
circuit breaker when several amps are turned on simul-
taneously.
Fig. 3.16 Loudspeaker Fuse Nomograph
1.0
1.2
1.4
1.6
2.5
3
4
5
6
7
8
9
10
12
14
16
20
25
30
20
15
10
8
6
5
4
3
2
1.5
1
.8
.6
.5
.4
.3
.2
.15
.1
.08
3000
2000
1500
1000
800
600
400
300
200
150
100
80
60
40
30
20
15
10
8
6
4
3
2
1.5
1
SPEAKER Z
(ohms)
FUSE
(amps)
SPEAKER RATING
PEAK MUSIC POWER
(watts)
(Typically 4 times the continuous average power)
Example: Z = 8 ohms.
Peak Power = 75 W
Answer: Fuse = 1.5 A
2
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