Crown Com-Tech 1610, Руководство по обслуживанию

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Com-Tech 810 and 1610 Amplifier Service Manual
]
3-1
Rev. 0
3 AC Power Draw and
Thermal Dissipation
“Soft-Star “Soft-Star
“Soft-Star “Soft-Star
“Soft-Start” t”
t” t”
t” inrush current limiting protects the house
circuit breaker when several amps are turned on simul-
taneously.
This section provides detailed information about the
amount of power and current drawn from the AC mains
by the
Com-Tech amplifiers and the amount of heat pro-
duced under various conditions. The calculations pre-
sented here are intended to provide a realistic and
reliable depiction of the amplifier. The following assump-
tions or approximations were made:
• The amplifier’s available channels are loaded, and full
power is being delivered.
• Amplifier efficiency at standard 1 kHz power is estimated
to be 65%.
• In 8/4 ohm mode, typical quiescent power draw is 55
watts for the Com-Tech 810 and 70 watts for the Com-
Tech 1610.
• In 70 volt mode, typical quiescent power draw is
90 watts for the
Com-Tech 810 and 1610.
• When running at full speed, typical power draw for the
internal fan is 11 watts for the Com-Tech 810 and 17
watts for the Com-Tech 1610.
• Quiescent thermal dissipation is related .
• The estimated duty cycles take into account the typical
crest factor for each type of source material.
• Duty cycle of pink noise is 50%.
• Duty cycle of highly compressed rock ‘n’ roll midrange
is 40%.
• Duty cycle of rock ‘n’ roll is 30%.
• Duty cycle of background music is 20%.
• Duty cycle of continuous speech is 10%.
• Duty cycle of infrequent paging is 1%.
Here are the equations used to calculate the data pre-
sented in Figures 3.1 and 3.2:
AC Mains Power
Draw (watts)
=
Total output power with all
channels driven (watts)
x Duty
Cycle
Amplifier Efficiency (.65)
+ Quiescent Power
Draw (watts)
The value used for quiescent power draw includes both
the amplifier’s quiescent power draw for the selected
output mode and the power drawn by the fan if one is
installed (these values are listed in the previous column).
The following equation converts power draw in watts to
current draw in amperes:
Current Draw
(amperes)
=
AC Mains Power
Draw (watts)
x
AC Mains
Voltage
Power
Factor (.83)
The power factor of 0.83 is needed to compensate for
the difference in phase between the AC mains voltage
and current. The following equation is used to calculate
thermal dissipation:
Total output power with all
channels driven (watts)
Thermal
Dissipation
(btu/hr)
=
+
Quiescent Power
Draw (watts)
x .35
Duty
Cycle
x
Amplifier Efficiency (.65)
( )
x 3.415
The constant 0.35 is inefficiency (1.00–0.65) and the fac-
tor 3.415 converts watts to btu/hr. Thermal dissipation in
btu is divided by the constant 3.968 to get kcal. If you
plan to measure output power under real-world condi-
tions, the following equation may also be helpful:
Total measured output power
from all channels (watts)
Thermal
Dissipation
(btu/hr)
=
+
Quiescent Power
Draw (watts)
.35
x
Amplifier Efficiency (.65)
( )
x 3.415
Figure 3.1 Com-Tech 810 Power Draw, Current Draw and Thermal Dissipation at Various Duty Cycles
3-1
Figure 3.2 Com-Tech 1610 Power Draw, Current Draw and Thermal Dissipation at Various Duty Cycles
8 Ohm Dual / 16 Ohm Bridge-Mono / 4 Ohm Parallel-Mono
L O A D
50%
40%
30%
20%
10%
535
440
350
255
160
785
670
560
450
335
820
670
520
370
220
285
240
195
150
100
810
670
525
385
245
1190
1020
850
680
510
6.4
5.3
4.2
3.0
1.9
9.9
8.0
6.2
4.4
2.6
9.7
8.0
6.3
4.6
2.9
Duty
Cycle
AC Mains
Power
Draw
(Watts)
btu/hr
Current Draw (Amps)
2.9
2.4
1.9
1.4
0.9
4.5
3.7
2.8
2.0
1.2
4.4
3.6
2.9
2.1
1.3
4 Ohm Dual / 8 Ohm Bridge-Mono / 2 Ohm Parallel-Mono 70 V
Com-Tech 810
200
170
140
115
85
kcal/hr
1125
945
765
585
405
300
260
215
170
130
100-120 V 220-240 V
Thermal Dissipation
btu/hr
Current Draw (Amps)
kcal/hr 100-120 V 220-240 V
Thermal Dissipation
btu/hr
Current Draw (Amps)
kcal/hr 100-120 V 220-240 V
Thermal Dissipation
AC Mains
Power
Draw
(Watts)
AC Mains
Power
Draw
(Watts)
8 Ohm Dual / 16 Ohm Bridge-Mono / 4 Ohm Parallel-Mono
L O A D
50%
40%
30%
20%
10%
920
755
590
425
260
1300
1100
905
705
510
1435
1165
895
630
360
485
400
320
240
160
1590
1295
1000
700
405
2140
1790
1435
1085
730
11.1
9.1
7.1
5.1
3.1
17.3
14.0
10.8
7.6
4.3
19.1
15.6
12.0
8.4
4.9
Duty
Cycle
AC Mains
Power
Draw
(Watts)
btu/hr
Current Draw (Amps)
5.0
4.1
3.2
2.3
1.4
7.8
6.4
4.9
3.4
2.0
8.7
7.1
5.5
3.8
2.2
4 Ohm Dual / 8 Ohm Bridge-Mono / 2 Ohm Parallel-Mono 70 V
Com-Tech 1610
330
280
230
180
130
kcal/hr
1915
1590
1270
950
630
540
450
365
275
185
100-120 V 220-240 V
Thermal Dissipation
btu/hr
Current Draw (Amps)
kcal/hr 100-120 V 220-240 V
Thermal Dissipation
btu/hr
Current Draw (Amps)
kcal/hr 100-120 V 220-240 V
Thermal Dissipation
AC Mains
Power
Draw
(Watts)
AC Mains
Power
Draw
(Watts)