Niles TVA-50 Troubleshooting guide

TVA50
STEREO AMPLIFIER/ AUTOMATED SWITCHER
TVA50
BLENDING HIGH FIDELITY AND ARCHITECTURE®
INSTALLATION & OPERATION GUIDE
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TABLE OF CONTENTS
Introduction 3
Features and
Benefits 4
TVA50 Parts
Guide 5
Installation
Considerations 11
Installation 13
Trouble-
Shooting 23
Specifications 24
Contents 24
STEREO AMPLIFIER/ AUTOMATED SWITCHER
TVA50
STEREO AMPLIFIER/
AUTOMATED SWITCHER
IMPORTANT SAFETY INSTRUCTIONS
1. Read these instructions.
2. Keep these instructions.
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water.
6. Clean only with dry cloth.
7. Do not block any ventilation openings. Install in accor-
dance with the manufacture’s instructions.
8. Do not install near any heat source such as radiators, heat
registers, stoves, or other apparatus (including amplifiers)
that produce heat.
9. Do not defeat the safety purpose of the polarized or
grounding-type plug. A polarized plug has two blades with
one wider than the other. A grounding type plug has two
blades and a third grounding prong. The wide blade or
the third prong are provided for your safety. If the provid-
ed plug does not fit into your outlet, consult an electrician
for replacement of the obsolete outlet.
10. Protect the power cord from being walked on or pinched
particularly at plugs, convenience receptacles, and the
point where they exit from the apparatus.
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
11. Only use attachments/accessories specified by the manu-
facture.
12. Unplug this apparatus during lightning storm or when
unused for long periods of time.
13. Refer all servicing to qualified service personnel. Servicing
is required when the apparatus has been damaged in any
way, such as power-supply cord or plug is damaged, liquid
has been spilled or objects have fallen into the apparatus,
the apparatus has been exposed to rain or moisture, does
not operate normally, or has been dropped.
14. WARNING: To reduce the risk of fire or electric shock, this
apparatus should not be exposed to rain or moisture and
objects filled with liquids, such as vases, should not be
placed on this apparatus.
15. To completely disconnect this equipment from the main,
disconnect the power supply cord plug from the receptacle.
CAUTION: TO REDUCE
THE RISK OF ELECTRICAL
SHOCK, DO NOT REMOVE
COVER. NO USER-SERVICE-
ABLE PARTS INSIDE. REFER
SERVICING TO QUALIFIED
SERVICE PERSONNEL.
CAUTION
The lightning flash with arrowhead symbol, within
an equilateral triangle, is intended to alert the user
to the presence of uninsulated dangerous voltage
within the product’s enclosure that may be of
sufficient magnitude to constitute a risk of electric
shock to persons.
The exclamation point within an equivalent
triangle is intended to alert the user to the
presence of important operating and maintenance
(servicing) instructions in the literature accompany-
ing the appliance.
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
INTRODUCTION
A common challenge in designing whole-house audio/video
distribution systems is allowing a local source, such as audio
from a bedroom TV, to play through the main system speakers
in that room. The TVA50 is the perfect solution. When
activated, by either current sensing or a voltage trigger the
TVA50 interrupts the main system’s speaker level signal, and
switches to the local source. When the device (TV) is turned
OFF, the speakers are switched back to the main system’s
audio program.
The TVA50 delivers the quality of audio amplification needed
to match the high performance amplifiers used in whole-house
systems. The TVA50 is also the perfect companion for added
flexibility in whole-house systems using Niles SI Series Multi-
Channel Amplifiers, or ZR Series Multi-Zone Receivers.
Whatever the application, switching to a local TV, computer,
portable CD or MP3 player, the TVA50 is the clear choice of
professional installers who need solid, reliable performance
from an automated switching amplifier.
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
FEATURES AND BENEFITS
• Compact Size - Allows installation on cabinet shelves, side
walls or back panels.
• RCA Line In Jacks - Two gold plated RCA jacks for line level
audio input from local device.
• 4 Pin Screwless Speaker Connectors
• Efficient Digital Technology - TVA50 incorporates digital
amplifier technology to deliver high output from a small
footprint.
• Current Sense - The current sensing circuit provides reliable
switching between the whole house and the local source.
• Trigger In - The presence of 3-30VAC/DC at the TRIGGER IN
terminal switches the TVA50 to the local source.
• 12VDC Trigger Out - Any time the TVA50 is switched to local
source, a 12VDC 200mA trigger voltage is emitted and can
be used to control other devices.
• Volume Control - Adjusts the TVA50 amplifier output level.
• Multiple Speaker Pairs - The TVA50 allows automated switch-
ing of either one or two pairs of speakers.
• 4 ohm Capability - The TVA50 is designed to remain stable
with a 4 ohm load.
• DC, Short Circuit and Overload Protection - An automatic
protection circuit safeguards TVA50.
• 2 Year Warranty - Two year parts and labor warranty.
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
TVA50 PARTS GUIDE
1. AC IN – Removable three-prong IEC compatible power cord.
2. Current Sensing AC Outlet – TVA50 will activate and switch
inputs when it senses a current draw from a connected
device.
3. Voltage Trigger IN – 3.5mm mini-phone jack. TVA50 will acti-
vate and switch inputs when 3-30 volts AC or DC is present.
4. 12V Trigger OUT – 3.5mm mini-phone jack. 12VDC 200mA
control output for automated control of lifts, screens, drapes,
etc.
5. Audio Line IN – Gold plated RCA type connectors. Local
source input. TVA50 switches to this input in either current
sense or 12V Trigger IN modes.
6. Volume Control – Adjusts TVA50 amplifier output level.
7. Speaker A Input/Output – Four-pin speaker connector plugs.
Screwless and removable for easy installation.
8. Speaker B Input/Output – Four-pin speaker connector plugs.
Screwless and removable for easy installation.
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
Figure 1
Figure 2
21
34 5 6 7 8
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
Speaker (A)
To Speaker
(A) Input
Right Left
Whole House Receiver
TV - Local Room
Right/Left
TV Variable
Line Out
TV - Power
Cord
To Current Sensing Outlet
TVA-50
To Unswitched
Outlet
Speaker
(A) Out
Figure 3
TV current sense with one speaker pair
Right Left
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
Speaker (A)
Speaker (A) Out Right
Left
Whole House Receiver
TV - Local Room
Right/Left
TV Variable
Line Out
TV - Power
Cord
To Current Sensing Outlet
TVA-50
To Unswitched
Outlet
To Speaker
(A) Input
Figure 4
TV current sense with two pair of 8 ohm speakers
To Speaker (B) Input
Speaker (B) Out
Left
Right
Speaker (B)
Left
Right
Right
Left
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STEREO AMPLIFIER/ AUTOMATED SWITCHER
Speaker (A)
Speaker (A) Out
Right Left
Whole House Receiver
TV - Local Room
Right/Left
TV Variable
Line Out
TV - Power
Cord To Current Sensing Outlet
TVA-50
To Unswitched
Outlet
To Speaker (A) Input
Figure 5
TV current sense with one speaker pair and a TV lift
IR Remote
12VDC Trigger
out to TV lift
Niles MSU480
12VDC
Niles IR
Flasher
Right Left
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