Camco D-POWER 7 User manual

D-POWER
SERIES
USER MANUAL
D-POWER 7
P. 1
INFORMATION FOR USE FOR
D-POWER 7
TDA225USERGBA_12-2012
The leading version of this brochure is the English one which shall prevail
to the exclusion of the national translation on hand.
Copyright 2011-2012 by CAMCO Produktions- und Vertriebs-GmbH
für Beschallungs- und Beleuchtungsanlagen
Fischpicke 5, D-57482 Wenden, Germany
Telephone [phone]
Please visit our website www.camcoaudio.com for the latest version of this user manual. Please note that the leading version of CAMCO manuals is always the English one.
D-POWER
SERIES
D-POWER 7 USER MANUAL

D-POWER
SERIES
USER MANUAL
D-POWER 7
P. 2
IMPORTANT SAFETY INSTRUCTIONS
1. General
The amplifier may only be used in accordance with the information provid-
ed in the user manual. Before and during the usage of the amplifier please
ensure that all recommendations, especially the safety recommendations
as detailed in the user manual, are adhered to.
The D-POWER 7 amplifier is designed for the amplification of pulsed audio
signals. The amplifier should only be connected to speakers with an aver-
age impedance as indicated.
2. User Manual
Read the information for use (user manual) and heed all warnings. Keep
this user manual in a safe place during the lifetime of the amplifier. The
user manual forms an integral part of the amplifier. Reselling the amplifier
is only possible if the user manual is available. In case of reselling the
amplifier, the reseller has to document any changes made to the amplifier
in writing and pass the documentation on to the buyer.
3. Environments
Use this amplifier only in E1, E2, E3, or E4 environments according to
EN55103-2 “Electromagnetic compatibility – Product family standard for
audio, video, and audio-visual and entertainment lighting control appara-
tus for professional use – Part 2: Immunity”.
4. Mounting/Placement
Do not place this amplifier on an unstable cart, stand,
tripod, bracket, or table. The amplifier may fall caus-
ing serious injury and serious damage to the prod-
uct. Any mounting of the amplifier should follow the
manufacturer´s instructions. Only mounting accessory
shall be used which is recommended by the manufac-
turer.
5. Power Cord Protection
Power supply cords should be routed so that they are not likely to be
walked on or pinched by items placed upon them or against them, paying
particular attention to cords and plugs and the point where they exit from
the amplifier.
6. Heat
Do not use this amplifier near any heat sources such as radiators, heat
registers, stoves, or other apparatuses that produce heat.
7. Water and Moisture
Do not expose this device to rain or moisture. Do not use this amplifier
near water (for example swimming pools and fountains). Do not place any
objects containing liquids, such as bottles or glasses, on the top of the
unit. Do not splash liquids on the unit. IP-20 equipment. There is no protec-
tion against splashing water.
8. Ventilation
Slots and openings in the cabinet are provided for ventilation to ensure
reliable operation of the amplifier and to protect it from overheating. These
openings must not be blocked or covered. This amplifier should not be
installed unless proper ventilation is provided or manufacturer’s instruc-
tions have been adhered to.
9. Interference Of External Objects and/or Liquids with the Appliance
Never push objects of any kind into this amplifier through openings as they
may touch dangerous voltage points or short-out parts that could result in
fire or electric shock. Never spill liquid of any kind on the amplifier.
IMPORTANT SAFETY INSTRUCTIONS

D-POWER
SERIES
USER MANUAL
D-POWER 7
P. 3
10. Connections
When you connect the amplifier to other equipment, turn off the power and
unplug all of the equipment from the supply source. Failure to do so may
cause an electric shock and serious personal injury. Read the user manual
of the other equipment carefully and follow the instructions when making
the connections.
11. Lightning
For additional protection of this amplifier during lightning storms or when
it is left unattended and/or unused for long periods of time, unplug it from
the wall outlet. This will prevent damage to the amplifier due to lightning
and power line surges. Disconnection from the mains power supply can
only be achieved by removing the plug from the mains socket and by
external disconnecting all poles from the mains.
12. Damages that Require Service
Unplug this amplifier from the mains supply and refer to your dealer/dis-
tributor or other authorized repair workshop if any of the following situa-
tions occur:
if liquid has been spilled or objects have fallen into the amplifier
if the amplifier has been exposed to rain or moisture
if the amplifier has been dropped or damaged in any other way
if the power supply cord or plug has been damaged
when the amplifier exhibits a distinct change from its normal function
or performance
in case the amplifier has been used in a dusty environment for quite
a period of time
13. Servicing
All service and repair work must be carried out by a dealer/distributor
authorized by CAMCO. Do not attempt to service this amplifier yourself.
As opening or removing covers may expose you to dangerous voltage or
other hazards, the amplifier may only be opened by qualified personnel.
Please refer to your dealer/distributor.
14. Spare Parts
When spare parts are required, please ensure that the dealer/distribu-
tor only uses spare parts specified by the manufacturer. The use of un-
authorized spare parts may result in injury and/or damage through fire or
electric shock or other electricity-related hazards.
15. Safety Check
Upon completion of any service or repairs to this product, ask the dealer/
distributor to perform safety checks to determine that the amplifier works
properly.
Recommendations on how to carry out the safety test can be found in
DIN VDE 0701-1 “Maintenance, Modification and Test of Electronic Appli-
ances“.
16. Cleaning
Unplug this amplifier from the wall outlet before cleaning. Do not use liquid
or aerosol cleaners. Clean only with dry cloth.
17. Packaging and Shipping
When shipping the D-POWER 7 amplifier, always use the original shipping
carton and packing materials. For maximum protection repack the unit as
it was originally packed at the factory.
IMPORTANT SAFETY INSTRUCTIONS

D-POWER
SERIES
CAUTION – RISK OF ELECTRIC SHOCK – DO NOT OPEN.
WARNING – TO PREVENT FIRE OR SHOCK HAZARD, DO NOT
EXPOSE THIS AMPLIFIER TO RAIN OR MOISTURE.
CAUTION – HIGH VOLTAGE HAZARDS
EXIST WITHIN THIS PRODUCT.
REFER ALL SERVICING TO
AUTHORIZED PERSONNEL.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
THE LIGHTNING FLASH WITH ARROW HEAD SYMBOL ALERTS
THE USER TO DANGEROUSLY HIGH VOLTAGE AT THE OUTPUT
CONNECTORS! THAT COULD POTENTIALLY BE LIFE THREATENING.
THE LIGHTNING FLASH WITH ARROW HEAD SYMBOL IS INTENDED TO
ALERT THE USER TO THE PRESENCE OF UNINSULATED DANGEROUS
VOLTAGE WITHIN THE PRODUCT’S ENCLOSURE.
THE EXCLAMATION MARK IS INTENDED TO ALERT THE USER
TO IMPORTANT INSTRUCTIONS ALSO FOR MAINTENANCE IN THE
LITERATURE ACCOMPANYING THE AMPLIFIER.
THE AMPLIFIER MAY ONLY BE CONNECTED
TO A SOCKET WITH A PROTECTIVE EARTH CONDUCTOR.
USER MANUAL
D-POWER 7
P. 4
EXPLANATION OF SYMBOLS

D-POWER
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USER MANUAL
D-POWER 7
P. 5
EC Declaration Of Conformity In Accordance To EC Directives:
electromagnetic compatibility (Council Directive 2004/108/EC);
low-voltage electrical equipment (Council Directive 2006/95/EC)
Manufacturer´s Name:
CAMCO Produktions- und Vertriebs-GmbH
für Beschallungs- und Beleuchtungsanlagen
Manufacturer´s Address:
Fischpicke 5, D-57482 Wenden, Germany
Declares That The Product With The Model Name:
CAMCO Power amplifier D-POWER 7
Conforms To The Following Standards:
EN60065 Safety
EN55103-1 Emission
EN55103-2 Immunity
The operating conditions and application environments presupposed in
the information for use (user manual) are to be kept to accordingly.
Wenden, 07.10.2011
Joachim Stöcker
EC DECLARATION OF CONFORMITY

D-POWER
SERIES
USER MANUAL
D-POWER 7
P. 6
P. 2 IMPORTANT SAFETY INSTRUCTIONS
P. 4 EXPLANATION OF SYMBOLS
P. 5 EC DECLARATION OF CONFORMITY
P. 6 CONTENTS
P. 7 1 WELCOME
1.1 Welcome To CAMCO
2 THE AMP
2.1 Unpacking
P. 8 2.2 The Amplifier
P. 9 2.3 D-POWER 7 – The Front
2.4 D-POWER 7 – The Rear
P. 10 2.5 Factory settings
3 INSTALLATION
3.1 Mains supply
P. 11 3.2 On/Off Switch
3.3 Mounting
P. 12 3.4 Cooling
3.5 Ground Lift
3.6 Optional Feature
3.7 Mode Selector
P. 13 3.8 Wiring
3.8.1 E.U.I. and XLR Connection
3.8.2 Stereo Operation
3.8.3 Parallel Mono Operation
P. 14 3.8.4 Mono Bridge Operation
3.8.5 SPEAKON®Connection
P. 15 4 OPERATION
4.1 Controls
4.1.1 Volume Control
P. 16 4.1.2 Gain Selector
4.1.3 Gain and Input Sensitivity
4.1.4 Limiter Switch
P. 17 4.2 Indicators
4.2.1 On LEDs (multifunctional)
4.2.2 Signal LEDs
4.2.3 Output Current LEDs
4.2.4 Clip LEDs (multifunctional)
P. 18 4.2.5 Mode Indicators
P. 18 4.3 Power Amp Protection Systems
4.3.1 Clip Limiter
4.3.2 Under Impendance Limiter
4.3.3 SOA Protection
4.3.4 Speaker Protect Limiter
P. 19 4.3.5 DC Protection
4.3.6 DC Servo
4.3.7 Over Current Protection
4.3.8 Thermal Protection
4.4 Main Protections
4.4.1 Inrush Current Limitation
4.4.2 Mains Over Voltage Detection
4.4.3 Mains Failure Detection
4.4.4 Fuse Protection
P. 20 4.5 Main SMPS Protections
4.5.1 Over Current Protection
4.5.2 Thermal Protection
4.6 Fans
P. 21 4.7 Filter Cleaning
P. 22 5 TROUBLESHOOTING
5.1 On LED Flashing Sequences
P. 23 5.2 Problem: No Sound
5.3 Problem: No Sound or Sound Is Too
Low
5.4 Problem: No Channel Seperation
5.5 Problem: Distorted Sound
P. 24 5.6 Problem: Hiss
5.7 Problem: Squeals and Feedback
P. 25 6 SPECIFICATION
P. 27 7 TYPICAL PERFORMANCE DIAGRAMS
P. 30 8 WARRANTY INFORMATION
8.1 Summary of Warranty
8.2 Items Excluded from This Warranty
8.3 What CAMCO Will Do
8.4 How to Obtain Warranty Service
8.5 CAMCO’s Product Improvement
P. 31 9 SERVICE INFORMATION
P. 32 10 MAINTENANCE INFORMATION
P. 32 11 DECOMMISSIONING
P. 33 COMPANY INFORMATION
P. 34 NOTICES/CHANGES MADE TO THE
AMPLIFIER
CONTENTS

D-POWER
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USER MANUAL
D-POWER 7
P. 7
1.1 Welcome to CAMCO
Established in 1983, CAMCO has gained worldwide experience with
professional sound reinforcement technology. Within the audio market,
CAMCO specialises in the production and marketing of high quality power
amplifiers and sound systems for use both on tour and in static installa-
tions.
The success of the TECTON and VORTEX series power amps has made the
CAMCO name synonymous with professional quality, high performance
and utterly reliable power amps.
CAMCO’s commitment to research and development, seen not just in the
area of materials and technology but also most importantly in its highly
skilled and motivated workforce, is one of the keys to its ongoing success.
With its all-new D-POWER 7 power amp, CAMCO is pioneering a new di-
mension in professional power amp construction. The seamless combi-
nation of ground-breaking technology with proven safety elements is the
hallmark of the new amplifier.
Welcome to the new world of professional power amplifiers –
WELCOME TO CAMCO!
2.1 Unpacking
Please unpack and inspect your new amplifier for any damage that may
have occurred during transit. If damage is found, notify the transportation
company immediately. Only you the consignee may initiate a claim for
shipping damage. CAMCO will be happy to cooperate fully as needed.
Please save the shipping carton as evidence of damage for the shipper’s
inspection.
Even if the amplifier has arrived in perfect condition, save all packing mate-
rials so you will have them if you ever need to transport the unit.
NEVER SHIP THE AMPLIFIER WITHOUT THE ORIGINAL
PACKING MATERIALS.
When shipping the D-POWER 7 amplifier, always use the original shipping
carton and packing materials. For maximum protection, repack the unit as
it was originally packed at the factory.
1 WELCOME / 2 THE AMPLIFIER

D-POWER
SERIES
USER MANUAL
D-POWER 7
P. 8
2.2 The Amplifier
The D-POWER 7 is a Class-H power amplifier with a power output of:
•3 kW per channel @ 2 Ω
•6 kW in Mono Bridge @ 4 Ω
•6 kW in Parallel Mono @ 1 Ω
The D-POWER 7 power amplifier is fitted with Switched Mode Power Supply
(SMPS), which significantly reduces the weight and size (only 2U). Using
SMPS, the 3 symmetrical supply voltages of the power amplifier are more
stable than the power supplies used in conventional amplifiers.
The D-POWER 7 also uses a microprocessor for controlling and monitor-
ing the power amp. This has four main advantages over more traditional
power amp systems:
Reduced Distortion
Improved Noise Characteristics
Indication of Protection or Failures by different LED sequences
The D-POWER 7 has been designed as an intelligent and powerful amplifier
for performing specialised tasks within a complex audio system. Users can
adapt the power amp to meet their specific audio requirements before use.
Controls mounted on the front and the rear of the D-POWER 7 allow the dif-
ferent functions to be accessed.
Since some of the externally mounted controls have multiple functions,
it is important that users should familiarise themselves thoroughly with
the entire range of controls and programmable features before using the
power amp.
If you have any questions regarding features and/or functions of your
D-POWER 7, CAMCO will be pleased to offer you further information. Alter-
natively, contact your dealer or distributor.
2 THE AMPLIFIER

D-POWER
SERIES

   
      
    
1 2 3 4 5 6
12
78 9 10 11
13 14 15 16 17 18 19
20 21 22
USER MANUAL
D-POWER 7
P. 9
2.3 D-POWER 7 - The Front
1 Clip LEDs 7 Volume Control Channel A
2 Output Current LEDs 8 Volume Control Channel B
3 Signal LEDs 9 Removable Air Filter System
4 On LEDs 10 Cooling Air Inlet Vents
5 Parallel Mono Mode LED 11 On/Off Switch
6 Mono Bridge Mode LED
2.4 D-POWER 7 - The Rear
12 Rating Plate 18 Limiter Switch
13 SPEAKON®Connectors 19 Gain Selector
14 Cooling Air Outlet Vents 20 AC Power Connector
15 Input Ground Lift Switch 21 XLR - Line Inputs
16 Optional Feature Selector 22 XLR - Line Link Outputs
17 Mode Selector
2 THE AMPLIFIER

D-POWER
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
   
  
  
xxxxxxx
D-POWER 7
230 V ~ 50/60 Hz 12 A 1800 W
3000 W / 2 Ohm
USER MANUAL
D-POWER 7
P.10
2.5 Factory settings
D-POWER 7 amplifiers are delivered with the following factory settings
Front panel:
On/Off Switch Off Amplifier is switched off
Rear panel:
Input Ground Lift Grounded
Optional Feature Circle
Mode Stereo
Limiter SpP
Gain 26 dB
3.1 Mains supply
When mounting or connecting the amp always disconnect it from
mains. Only connect the D-POWER 7 amplifier to an appropriate AC cir-
cuit and outlet, according to the requirements indicated in the second
line on the rating plate.
Exemplary rating plate for a mains supply of 230 V AC 50/60 Hz.
Power Supply Data:
Voltage Mains Frequency Current Power Consumption
100 V 50/60 Hz 28 A 1800 W
120 V 50/60 Hz 24 A 1800 W
220 V 60 Hz 12 A 1800 W
230 V 50/60 Hz 12 A 1800 W
NOTE: Even under normal conditions the mains current can reach lev-
els up to 60 A (230 V), 120 A (120 V) and 140 A (100 V), respectively;
this could cause lamps to flicker if connected to the same mains as
the amp. The impedance of the AC circuit should be less than 0,157
Ohms to avoid flicker according to EN61000-3-11 “Electromagnetic
compatibility – Part 3-11: Limits – Limitation of voltage changes, volt-
age fluctuations and flicker in the public low-voltage supply systems
– Equipment with rated current
≤ 75 A and subject to conditional connection”.
If in any doubt, consult your local power provider. Never attempt to
measure this impedance level with your ohmmeter. This may damage
your meter and expose you to the risk of electric shock!
2 THE AMPLIFIER / 3 INSTALLATION

D-POWER
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USER MANUAL
D-POWER 7
P.11
3.2 On/Off Switch
The On/Off Switch is a rocker-type switch. It is located on the right side
of the front panel. To turn the amplifier on, press on the upper part of the
switch. During power up the Clip and Signal LEDs from both channels will
light up in red for a few seconds. To turn the amplifier off, press on the
lower part of the switch.
Amplifier is switched on Amplifier is switched off
NOTE: This switch does NOT disconnect the amplifier from mains.
Make sure the mains power socket or an alternative disconnect device
is nearby and easily accessible.
The switch initiates start-up by activating the inrush current limiter. As soon
as the power amplifier is connected to the mains power supply, a voltage is
supplied to both the line-filter and the fused input of the controllable recti-
fier. Disconnecting the amplifier from the main power supply can only be
achieved by physically separating the amplifier from the mains by pulling
the mains plug. The mains plug therefore has to be freely accessible. Dis-
connect the mains plug from the mains during a lightning storm or when
the amplifier remains unused or unsupervised for a prolonged period of
time. Alternatively, you can disconnect the amplifier via an external all-pole
disconnection from the mains.
If a power cut occurs while the amplifier is switched on, it will restart auto-
matically once the power supply has been restored. All amplifier settings
prior to the loss of power will be maintained.
3.3 Mounting
Use four screws and washers when mounting the amplifier to the front rack
rails. For mobile use, the amplifier should also be secured using the 19”
mounting elements on the rear panel.
443,00 mm
442,00 mm
483,00 mm
452,00 mm
465,00 mm
10,50 mm
7,50 mm
76,20 mm
3 INSTALLATION

D-POWER
SERIES
DO NOT REMOVE MAINS CONNECTOR GROUND
IT IS ILLEGAL AND DANGEROUS
to Pin 1
of the XLRs
USER MANUAL
D-POWER 7
P.12
3.4 Cooling
Under normal operation of the power amp, overheating should never be a
problem. The air is taken in from the front and out through the back. It is of
course essential that while the power amp is running air is able to circulate
around it freely.
The efficiency of the cooling will depend on the immediate environment
(e.g. an enclosed rack, direct sunlight) and on whether the front filter is
clogged. If the amp is installed in a case, the open area at the back of the
case must be at least 140 cm². This area should be in line with the amp.
If this can not be achived a forced ventilation system has to be used.
3.5 Ground Lift
The input signal ground (pin 1 for all 4 XLRs) is connected to the ground
of the mains supply. In order to avoid ground loops, this connection can
be separated via a resistor. The ground potential of the power amp and the
ground of the loudspeaker always remain connected to the ground of the
mains supply regardless of the setting of this switch.
Removing or taping the mains connector ground is illegal and dangerous.
3.6 Optional Feature
Could be activated with future released software versions.
3.7 Mode Selector
The switch on the rear panel changes the operating mode. Moving this
switch will shutdown the amplifier and restart it in the new operating mode.
3 INSTALLATION

D-POWER
SERIES
A (L)
B (R)
D-POWER 7
Z ≥ *Zmin
Z ≥ *Zmin
D-POWER 7
A
B
Zres ≥ 0,5*Zmin
Input
Ground
Lift
Input Ground Lift in
position: grounded
LINK BInput
Channel B
2
3
11
3
2 2
3
1
To
Channel B
To
Channel A
Input
Channel A
LINK A
3
12
USER MANUAL
D-POWER 7
P.13
3.8 Wiring
3.8.1 E.U.I. and XLR Connection
XLR: Pin 1 = Ground (or lifted via 15 Ω resistor)
Pin 2 = Hot (inphase)
Pin 3 = Cold (out of phase)
Always use symmetrical (balanced) shielded cable to connect the amplifier
3.8.2 Stereo Operation
Two fully independent amplifier channels (normal operating mode).
3.8.3 Parallel Mono Operation
Parallel operation of the two channels together.
The output terminals of the two channels are configured in parallel using
an internal relay. The (single) load is connected either to the output of
channel A or to that of channel B (as if in stereo). While the total output
of the amplifier remains the same and the output voltage level is also the
same as in stereo operation, the minimum impedance that can be con-
nected is reduced by half due to the fact that current capability is doubled.
Only channel A-Input is active. The channel B-Input is inactive – turn the
volume on channel B down to zero. This mode is useful when, for exam-
ple, 3 identical loudspeakers are to be operated with the same power.
3 INSTALLATION

D-POWER
SERIES
D-POWER 7
A
B
Z ≥ 2*Zmin
*Zmin = 2 Ω
Bottom SPEAKON
Upper SPEAKON
Input
Channel A
Input
Channel B
USER MANUAL
D-POWER 7
P.14
3.8.4 Mono Bridge Operation
One-channel mono bridged operation.
The second channel processes the same input signal, but with reversed
phase. The (single) load is connected between the two positive channel
outputs using a suitable connected SPEAKON®connector. While the total
output of the amplifier remains the same, both the available output volt-
age and the minimum impedance that can be connected are doubled, as
compared with stereo operation. Only channel A-Input is active – turn the
volume on channel B down to zero.
WARNING !
In Mono Bridge mode RMS output voltages are as high as 230 V. Wir-
ing to the speaker loads must conform to NEC Class 3 safety stand-
ards or its equivalent that meets all national and local electric codes.
All customer specific cables may only be manufactured by qualified
suppliers/personnel. All cabeling or rewiring work must be carried out
by qualified personnel.
3.8.5 SPEAKON®Connection
Both SPEAKON®connectors are connected to channel A and channel B
outputs. The pin configuration of the SPEAKON®connectors is as follows:
Upper SPEAKON®: Pin 1+ Channel A signal
Pin 1- Channel A ground
Pin 2+ Channel B signal
Pin 2- Channel B ground
Bottom SPEAKON®: Pin 1+ Channel B signal
Pin 1- Channel B ground
Pin 2+ Channel A signal
Pin 2- Channel A ground
WARNING!
SPEAKON®connectors marked with the lightning flashes indicate
high voltages that are potentially life threatening.
Wiring to these terminals requires installation by an instructed person
or the use of ready-made leads or cords.
Custom wiring should only be carried out by qualified personnel.
3 INSTALLATION

D-POWER
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USER MANUAL
D-POWER 7
P.15
To prevent electric shock, do not operate the amplifier with any of the
conductor portion of the speaker wire exposed.
NOTE:
For reasons of safety and performance, use only high-quality fully in-
sulated speaker cables of stranded copper wire. Use the largest wire
size that is economically and physically practical, and make sure the
cables are no longer than necessary.
IMPORTANT:
When connecting speaker cabinets in parallel, always use all the con-
tacts in both SPEAKON®connectors. If not, this may cause permanent
damage to the connectors and considerably reduce performance.
4.1 Controls
4.1.1 Volume Control
A microprocessor-controlled DCA (Digital Controlled Attenuator) with a
control resolution of 12 bits per channel is integrated into the signal path.
This means that the signal is not subject to an A/D followed by a D/A con-
version with associated losses and delay.
Using a DCA instead of the “conventional” VCA significantly reduces dis-
tortion and, at the same time, it improves the noise characteristics. A vol-
ume control with 41 notched settings controls the DCA via a microchip.
These settings have been selected to correspond to human hearing char-
acteristics and therefore guarantee an optimal range of settings for practi-
cal applications. Each channel can be set individually except when operat-
ing in mono modes whereby only channel A is active.
Set the volume to zero before turning on the amplifier to prevent the oc-
currence of sudden high volume levels which may cause damage to your
hearing and/or the speakers.
3 INSTALLATION / 4 OPERATION

D-POWER
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USER MANUAL
D-POWER 7
P.16
4.1.2 Gain Selector
This switch on the rear of the D-POWER 7 allows the maximum amplification
attainable to be set directly in the input stage.
The D-POWER 7 amplifier has a 26 dB and 32 dB voltage gain setting along
with a 1,4 V sensitivitysetting.
4.1.3 Gain and Input Sensitivity
The table shows input sensitivity per channel for a given gain and load. It
also shows the gain for the 1,4 V input sensitivity.
26 dB 32 dB 1,4 V
3500 W @ 2 Ω
2500 W @ 4 Ω
1450 W @ 8 Ω
4,19 V
5,01 V
5,40 V
2,10 V
2,51 V
2,71 V
37,5 dB
4.1.4 Limiter Switch
This switch is located at the rear of D-POWER 7. It allows you to set the
mode of the limiter. There are three modes (See 4.3.1 Clip Limiter and 4.3.4
Speaker Protect Limiter):
Right position:
Clip Limiter: On
Speaker Protect: On
Middle position:
Clip Limiter: Off
Speaker Protect: On
Left position:
Clip Limiter: Off
Speaker Protect: Off
4 OPERATION

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USER MANUAL
D-POWER 7
P.17
4.2 Indicators
4.2.1 On LEDs (multifunctional)
Under normal operation, after the amp has started, the green On LEDs are
permanently lit. A variety of different sequences of flashing LEDs are used
to indicate other operating states and errors in the relevant channels of the
power amp (See 6.1 Flashing sequences for On LEDs).
4.2.2 Signal LEDs
The green Signal LED is illuminated when the voltage level at the output
reaches approx. 4 V; this corresponds to a power of approx. 4 W over a
4 Ohm resistor.
4.2.3 I-Out LEDs
The brightness is proportional to the output current in the corresponding
channel.
4.2.4 Clip LEDs (multifunctional)
The colour of the bi-coloured LED changes between orange and red, de-
pending on the clip intensity. Orange indicates light clipping, red indicates
heavy clipping.
4 OPERATION

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USER MANUAL
D-POWER 7
P.18
4.2.5 Mode Indicators
On the front panel there are two yellow LEDs to indicate the mode that is
set. In stereo mode (2-channel) none of them will be lit. In Parallel Mono
the (PM) LED will be lit and in Mono Bridge, the (MB) LED will be lit.
Amplifier in Parallel Mono mode
Amplifier in Mono Bridge mode
4.3 Power Amp Protection Systems
4.3.1 Clip Limiter
If the power amp is overdriven, the clip detection circuit triggers the micro-
processor. The processor reduces input signal level by controlling the
DCA. The strategy is implemented in software. For sinusoidal input signals
the microprocessor limits the input signal in such a way that non-linear
distortions of the signal never exceed 1 %.
The Clip Limiter can work on each channel independently (except in the
two mono operation modes). (To disable the Clip Limiter, see 4.1.4 Limiter
Switch.)
4.3.2 Under Impedance Limiter
As a result of incorrectly connected or defective loads, under impedance
or even short circuits may occur in one or both power amp channels.
The microprocessor constantly calculates the load impedance at the out-
put channels. If an impedance of less than 1,33 ohms/channel is detected,
the microprocessor limits the signal to the power amp until a subsequent
measurement indicates that impedance has risen to a safe level. When-
ever the Under Impedance Limiter is active, the corresponding channel’s
On LED is turned off (See 5 Troubleshooting).
4.3.3 SOA Protection
To ensure that the power transistors are only used in the Safe Operation
Area (SOA), the SOA-protection in stereo mode switches back the rail volt-
ages of the respective power stage. In mono modes the rail voltages of
both channels are switched back.
4.3.4 Speaker Protect Limiter
Whenever the SOA protection of the power amp switches back the current
rail there could be a small clipping at the output; but the microprocessor
is also triggered by this protection and will reduce the signal level immedi-
ately to minimise the effect.
The user can decide either to use Speaker Protect or not. If you use this
amp for low frequencies (bass / Sub bass) and you want to squeeze the
absolute maximum out of it, Speaker Protect can be switched off. For all
other applications (e.g. Full Range) it’s recommended to keep Speaker
Protect switched on.
4 OPERATION

D-POWER
SERIES
USER MANUAL
D-POWER 7
P.19
4.3.5 DC Protection
Each output of the power amp is constantly monitored for persistent DC
voltage levels. If the 3 V threshold voltage is exceeded at any of the out-
puts, the main SMPS will shut down and the channel will be automatically
switched off. The microprocessor performs a sophisticated strategy to lo-
cate the cause of the malfunction. DC can be located in the output stage,
driver stage or at the input of the amplifier.
Output Stage
When a DC voltage is located at an output stage, the main SMPS remains
switched off. The On LEDs will show a flash sequence corresponding to
this malfunction (See 5 Troubleshooting).
Driver Stage
When a DC voltage is located at the driver stage only the defective chan-
nel’s output stage and the DCA are muted. The other channel continues to
work. The On LED of the defective channel will indicate the malfunction by
starting the relevant flash sequence (See 5 Troubleshooting).
Amplifier Input
When DC is located at the input stage only the DCA of the affected chan-
nel is muted. The other channel continues to operate normally. If the DC
signal at the input vanishes, the microprocessor will de-mute the affected
channel and the amplifier will work as usual again.
4.3.6 DC Servo
To prevent DC Offset at the speaker output the D-POWER 7 is fitted with two
DC Servos. (Hence there are no capacitors in the signal path)
4.3.7 Over Current Protection
The output stage is permanently monitored for possible current surges.
There are two limiting levels of over current depending on output voltage.
These limits will be set automatically. This improves reliability without de-
grading sound quality when driving complex loads.
4.3.8 Thermal Protection
The microprocessor uses several sensors in the amp in order to ascertain
temperature data. If the microprocessor detects a temperature of more
than 85 °C at the heat sinks, the input signal on that channel is reduced. If
the temperature exceeds 100 °C, the main SMPS is switched off.
The On LED of the overheated channel will start a blinking-sequence (See
5 Troubleshooting).
4.4 Mains Protections
4.4.1 Inrush Current Limitation
Within 2 seconds of the D-POWER 7 being switched on, the inrush current
limiter will increase mains current from nearly zero to nominal value. This
value depends on program material, output level and speaker loads.
4.4.2 Mains Over Voltage Detection
Mains Over Voltage Detection is always operative. When the mains voltage
exceeds approx. 267 V (230 V operation), 134 V (120 V operation) or 117
V (100 V operation), the amplifier will switch off. When the mains voltage
returns to nominal value, a soft start occurs.
4.4.3 Mains Failure Detection
Mains Failure Detection is always operative. When the mains supply is
interrupted for about 2 mains cycles, the amplifier will switch off. When the
mains voltage returns to a normal value, a soft start occurs.
4.4.4 Fuse Protection
The average mains current can peak temporarily, depending on the load
impedance and type of signal, at values several times higher than the
nominal value allowed by the fuse protection.
Continuous monitoring of the fuse protection status allows the conditions
that would trigger the fuse protection to be predicted. In order to avoid
shut-down of the amplifier due to current overload, the amplitude of the
input signals will be limited.
The limitation of the input signal allows a 6 kW D-POWER 7 power amplifier to
be operated reliably from a mains power supply of 230 V/16 A (120 V/30 A;
100 V/30 A).
4 OPERATION