Knoll VC220 Installation Instructions

VC220
Digital Volume Control
Installation Instructions
Warning: To be installed and/or used in accordance with appropriate electrical
codes and regulations.
Caution: Do not install these keypads in an electrical junction box with 110V or
higher unless an approved barrier separates the high and low voltage sections.
Description: The Knöll VC220 digital volume control attenuates stereo speaker signals
in 17 steps. On it's top step it directly connects the speaker to the amplifier. The
VC220pm is also available which includes Powermatch circuitry allowing up to eight
VC220pms to be connected to a receiver with out a load matching interface.
The VC220 includes mute and start-up functions. The VC220 is controlled with a VC200
or VC201 keypad or an external controller such as the VCI-28 interface. Up to three
keypads can be connected (daisy chained) to a VC220. The VC200i and VC201i keypads
contain an internal infrared receiver (no extra wiring is necessary) to control the stereo
and other systems. The VC220 requires a 12VDC power supply, is usually wall-mounted
and works best if mounted vertically.
Basic System Layout and Pre-Wiring: See "Typical Wiring Diagram" on the back
page. When changing volumes the VC220 makes a noticeable "click" sound. We suggest
mounting it in a low voltage panel, electrical room, closet, etc. VC200's and VC201's
cannot control the same VC220. Only one VC200i or VC201i can be connected to a
single VC220pm.
Use the standard T568A wiring practices to run a cat 5 or cat 3 wire from the keypad or
controller to the VC220. If more than one keypad controls a single VC220, daisy chain
the wire from keypad to keypad. If the VC220(s) are not located next to the stereo, run a
single eight-conductor cat 3 or cat 5 wire run from the stereo to the VC220(s) for the
power supply, the infrared system and future upgrades such as paging override. Like
conventional speaker volume controls the VC220 may require a stereo interface (such as
the Knöll WIN600) if multiple VC220s are connected to a single receiver.
From each VC220 run a fire rated two-conductor speaker wire to each speaker. To save
time and money, most installers run a four-conductor speaker wire from the VC220 to the
closest appropriate speaker and then run a short two-conductor speaker wire to the other
speaker. If there is more than one pair of speakers connected to a single VC220, the
speakers can be wired in series or parallel whichever makes the impedance closest to 4 or
8 ohms.
Do not attempt to make the final combined speaker impedance less than 4 ohms.
If the VC220(s) are not located next to the stereo, run a single fire rated four-conductor
(or two two-conductor) 14-18 gauge speaker wire from the stereo to the VC220(s).
Connecting VC200/VC201 keypads to VC220 controllers:
Use a single cat5 wire using all eight conductors (usually run inside a wall). Always use
standard T568A Cat 5 wiring practices (shown below). Use the correct wire pairs.
Polarity is VERY important! The stereo signal is not routed to the keypad, just the digital
control signals. Signals from an infrared receiver (if used) are routed down the same Cat
5 wire. If more than one keypad is to be connected to a VC220 controller, the wires to the
keypads are paralleled.
brown 8
white/brown 7
orange 6
white/blue 5
blue 4
white/orange 3
green 2
white/green 1
Connection to Stereo Equipment: Remove the VC220 eight-position speaker
connector. The stereo amplifier or receiver outputs (left and right) are connected to the
VC220 connector labeled "TO AMP". Be very careful to observe the correct polarity.
The VC220 uses independent floating grounds so bridged amplifiers can be used safely.
***The VC220pm is rated for use with maximum
120 watt per channel amplifiers. DO NOT use
higher-powered amplifiers with this product
for safety reasons.***
Depending on the receiver or amplifier rated impedance you may be able to connect more
than one VC220. For multiple connections of VC220's an impedance matching interface
such as the WIN600 or SI1x6 may be required. Wire from the amplifier speaker terminals
are always wired in parallel to the VC220 controllers "TO AMP" terminals either by
stripping and soldering, using a speaker wire paralleling board, or daisy chaining from
one VC220 connector to the next VC220 connector etc. Connect all VC220's to amplifier
speaker A or speaker B terminals, but not both. Wire the VC220 connectors labeled
"SPEAKER" directly to the correct speakers, again strictly observing polarity.
Power Requirements: The VC220
needs a 12vdc power supply. The
VC220 controller supplies power to the
keypads. A maximum of 60mA is
needed for each VC220. If possible,
connect the 12vdc power supply to the
switched outlet on the rear of the
amplifier or receiver. By doing this the
digital volume control resets to its
installer selectable "boot up" every
VC201i keypads are connected
to VC220 controllers, the same
as other keypads, the only
difference is extra VC220
wiring is required (see Infrared
connection diagram below).
VC220/VC220pm
POWER INFRARED
+12V G 12V SIG
Stereo
-
+
+ -
12VDC power supply
12VDC power supply plugged plugged into power
Infrared
into stereo switched outlet full time
emitter(s)