Extron electronics SF 228T Plus User manual

1
IMPORTANT:
IMPORTANT:
Go to www.extron.com for the
product specifications.
SF 228T Plus • Setup Guide
General Setup
The SF228T Plus features a low prole design that houses an 8-inch woofer and 1-inch dome tweeter and has the appearance of
a standard ventilation grill. All drivers and components above the ceiling are hidden behind the grill.
The SF228T Plus is used in plenum rated ceiling spaces and can be mounted into a standard 2 feet x 2 feet or 2 feet x 4 feet
(with supplied t-rail crosspieces) false ceiling tile space on a T-bar grid, or, a frame installed in solid ceilings.
Application Example
The following illustration shows one way to congure a system using the SF 228T Plus.
NetPA U 1002 SERIES
LIMITER/PROTECT
SIGNAL
OVER
TEMP 21
mute selectmute select
AUDIO
Extron
NetPA U 1002-70V
Power Amplier
Ethernet
Audio Line
Inputs Audio Line Outs
Wireless Mic 1
Wireless Mic 2
Ext
ron
SF
228T Plus
Pl
enum 2' x 2'
Ceiling Spea
ker
Ext
ron
SF
228T Plus
Pl
enum 2' x 2'
Ceiling Spea
ker
Assistive Listening
System Transmitter
Extron
WPD 101 3.5 mm
Single Gang
Pass-Through
Wallplate
Figure 1. SF228T Plus Application Diagram
IMPORTANT:
IMPORTANT:
Go to www.extron.com for the complete
user guide, installation instructions, and
specifications before connecting the
product to the power source.

2
Installing the Speakers
CAUTION:
• Installation and service must be performed by authorized personnel only.
• L’installation et l’entretien doivent être effectués uniquement par du personnel autorisé
1. Power down —Power down all attached devices before proceeding.
2. Remove the suspended ceiling tile —Remove the ceiling tile where the SF228T Plus will be installed and lay it aside.
3. Remove the terminal cover plate — Loosen (do not remove) the two screws in the keyhole slots on the top terminal cover
plate and remove the cover plate as shown below.
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
E
E
E
Keyhole Slots
Te
rminal
Cover Plate
Loosen but do not remove
the two screws in the keyhole
slots on either side of the
cover plate.
Figure 2. Remove Terminal Cover Plate
4. Routing cables through the terminal cover plate — The cover plate is reversable.
a. When using flexible conduit — Insert the conduit into the cover plate opening using an appropriate conduit adapter,
and secure the conduit to the plate, (see the illustration below).
Speaker
Terminal
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100 V
70 V
E
E
E
E
Terminal Cover Plate
Flexible Conduit Adapter
Flexible Conduit
Secondary Knock-out
Figure 3. Flexible Conduit Adapter
NOTE: Installation of conduit and conduit adapters should conform to all applicable building codes and local
ordinances.

3
SF 228T Plus • Setup Guide (Continued)
b. When using speaker wires without conduit —Secure the cable clamp adapter (included) to the cover plate and insert
the wires through the clamp, (see the illustration below).
Speaker
Terminal
Cable Clamp
Adapter (Included)
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100 V
70 V
Terminal Cover Plate
E
E
E
E
Secondary Knock-out
Figure 4. Cable Clamp Adapter
Wiring the Speakers
Within the speaker terminal compartment, the red (+) and black (-) speaker wires are pre-attached to seperate three-pole splicing
connectors.
1. Route the two wires from the amplifier through the cable access opening to the two 3-pole splicing connectors. If conduit is
used, pull the wires coming from the amplifier through and out of the conduit.
2. Using the guide on the side of the splicing connector, strip 0.43 inch (11 mm) from the ends of the protruding black and red
wires. These wires will be inserted into the two 3-pole splicing connectors (included).
3. Lock the red and black power amplifier or speaker wires into their respective 3-pole splicing connectors.
a. Lift one lever of the red-wired 3-pole splicing connector 1and insert the stripped end of the red wire into the right-most
empty pole of the connector 2. Press the lever down to lock the red wire in place 3(see figure 5).
3
3
3
1
1
1
2
2
2
Figure 5. 3-pole Splicing Connector
b. Lift one lever of the other (black-wired) 3-pole splicing connector 1and insert the stripped end of the black wire into
the right-most empty pole of the connector 2. Press the lever down to lock the black wire in place 3.
3
3
3
1
1
1
2
2
2
NOTE: Each pole of the splicing connector can accept up to 12 AWG wire.

4
4. To wire additional speakers —
a. Measure the distance between the two speakers intended installlation points, add an extra foot or third of a meter for
safety, and cut that length in speaker wire cable.
TIP: Estimate the distance by counting the number of 2 x 2 inch or 2 x 4 inch ceiling tiles.
b. Remove the secondary knock-out from the terminal cover plate of the primary speaker, and route one end of the speaker
cable through the secondary cable access opening. If conduit is used, pull the wires through and out of the conduit (see
figure 6).
From Amplifier
or Previous
Speaker
Red Wire
Black Wire
Black Wire
Red Wire
To Next
Speaker
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100 V
70 V
E
E
E
E
Figure 6. Routing Second Speaker Wires through Primary Speaker Cover Plate
c. The red speaker wire connects into the empty pole of the red wire splicing connector, and the black speaker wire
connects into the empty pole of the black wire splicing connector. The order of wires has no effect on function.
d. For wiring the second speaker, repeat step 1 of Installing the Speakers (page 2) through step 3 of Wiring the Speakers
(page 3).
e. For additional speakers, repeat step 4 as necessary.
5. Replace the terminal cover plate and tighten the two cover plate screws that were loosened in step 3of Installing the
Speakers on page 2.
6. Set the rotary tap selector switch to the appropriate setting using a small screwdriver.
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
E
E
E
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
Adjust the Tap Selector
100 V
70 V
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
Figure 7. Rotary Tap Selector Switch
ATTENTION:
• When setting the taps for a distributed (high impedance) system, do not tap the system above the rated power of
the amplifier.
• Lors de la mise en place des capteurs pour un système distribué (haute impédance), n’exploitez pas le système au
delà du niveau d’alimentation de l’amplificateur.
• When connecting multiple speakers in 8-ohm mode, be sure that the combined rated impedance does not equal a
value less than the minimum rated impedance of the amplifier.
• Lors de la connexion de plusieurs enceintes en mode 8 ohm, assurez vous que le niveau d’impédance combinée
ne soit pas équivalent à une valeur inférieure à l’impédance minimum de l’amplificateur.

5
SF 228T Plus • Setup Guide (Continued)
7. Test the system by powering on the amplifier and listening for the correct response from the speakers. Disconnect the power
from the amplifier.
Completing the Installation
NOTE: Observe all applicable building codes and local ordinances when installing the speaker.
1. For installation in a 2 feet x 2 feet ceiling tile —Remove a tile and place the speaker on the existing support rails as shown
below.
Extr
on
SF 228T Plus
T
wo-way Ceiling
Speakers
Ceiling Tile
Rails
2' x 2'
Ceiling Tile
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
E
E
E
Figure 8. 2 Feet x 2 Feet Ceiling Tile Installation
For installation in a 2 feet x 4 feet ceiling tile —Remove a tile and cut the tile in half. Install the supplied T-rail crosspiece,
then replace the half-tile as shown below.
Extron
SF 228T Plus
Two-way Ceiling
Speakers
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
Existing
Ceiling Tile
Rails
T-rail
Crosspiece
(supplied)
2' x 4'
Ceiling Tile
E
E
E
Figure 9. 2 Feet x 4 Feet Ceiling Tile Installation
2. Set the speaker in place in the ceiling and position it so the speaker edges are hidden by the existing rails or T-rails.

6
68-3387-50 Rev. A
11 20
For information on safety guidelines, regulatory compliances, EMI/EMF compatibility, accessibility, and related topics, see the
Extron Safety and Regulatory Compliance Guide on the Extron website.
©2020 Extron — All rights reserved. www.extron.com
All trademarks mentioned are the property of their respective owners.
Worldwide Headquarters: Extron USA West, 1025 E. Ball Road, Anaheim, CA 92805, 800.633.9876
3. If seismic safety lines are being used, install them now. In addition to the tie off at BandC, Extron recommends a tie off on
at least one of the four available tabs at A. See the illustration below.
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
8Ω
8Ω
64W
32W
OFF
8W
16W
64W
32W
16W
OFF
100V
70V
B
B
B
C
C
C
Attach the seismic safety cable
to any of the four (4) bend up tabs.
Anchor the safety cables
to a suitable secure point.
Seismic
Safety
Cable
Bend Up Tab
Attach a safety cable
to either B or C
line retainer.
A
A
A
D
D
D
NOTE: Speaker wiring has been omitted for clarity.
CAUTION:
• Repeated bending may cause the tab to break off.
• La flexion répétée peut provoquer la rupture de l’onglet.
Figure 10. Install the Seismic Safety Lines
a. If necessary, shut off power to all connected equipment.
b. Temporarily remove a ceiling tile adjacent to the speaker and set it aside.
c. Attach seismic safety cable to one or both line retainer loops at Band C.
d. Attach seismic safety cable to at least one of the four (4) seismic bendout tabs located on either side of the speaker, A.
e. Attach the other end of the cables (D) to a sturdy part of the building (studs, roof struts, support girders or similar
structure).
f. For additional support lines, repeat as needed.
g. Replace the ceiling tile removed in step b.
4. Power on the amplifier, test and make any source device and system adjustments following the amplifier operating
instructions.