3M 478DA (D-15), Installation Manual

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WARNING:
All intercom and vehicle detection cables must route through a CONDUIT THAT IS SEPARATE from
that containing sign lighting. Do not, under any circumstances, route audio or low voltage cables in the
same conduit with 120 VAC wiring. This violates the National Electrical Code and presents a potential
hazard.
2. OUTSIDE SPEAKER/MIC - The D-15 intercom provides two-way communication to a remote 8-ohm speaker. A
weatherproof horn-type speaker is acceptable for most drive-thru applications, although best audio clarity is achieved
with the use of a separate speaker and microphone. The 3M OSM (78-8016-9810-7) can be used for most menu sign
and point-to-point communications. The 3M Security Speaker/Mic (78-8028-9047-1) is recommended for pass-
through window applications. Place the speaker at a height of 42 to 54 inches above the driveway surface to reduce
vehicle noise. Connect to the SPEAKER outputs as shown in figure 3.
3. SPLIT SPEAKER AND MICROPHONE - The D-15 allows the connection of separate components for
incoming and outgoing audio. To select this option, set SW104 and SW105 to the OUTSIDE MIC position (see figure
1). A low-impedance dynamic microphone may be connected to the OUTSIDE MIC inputs and the outgoing audio will
still be on the SPEAKER outputs (see figure 3).
4. FLEX MICROPHONE - A low-impedance microphone may be substituted for the internal D-15 mic to place the
microphone closer to the operator for better voice clarity in noisy situations. Set SW102 & SW103 to the EXTERNAL
MIC position (see figure 1) and connect the microphone to the FLEX MIC and SHIELD inputs (see figure 3).
5. MONITOR SPEAKER - An 8-ohm speaker may be connected to the monitor outputs to monitor the incoming
conversation. Use twisted pair wire to connect this monitor speaker to the MONITOR HI (or MONITOR LO) and
COMMON outputs (see figure 3). MONITOR LO is the same power output as the internal speaker, MONITOR HI
outputs a higher level.
6. FOOTSWITCH - The Talk/Listen function of the D-15 can be controlled by an external footswitch normally open
contact. Connect the footswitch(s) to the FOOTSWITCH and COMMON inputs (see figure 4). The D-15 Talk/Listen
switch remains functional.
7. MULTIPLE MASTER SYSTEM - The Model 478DA allows the connection of two units to the same outside
speaker/microphone Connect the speaker outputs per figure 5. Route 2 twisted pair cables between the units and
connect to the BUSY, ALERT CANCEL, VEHICLE DET. +20VDC and COMMON inputs of each unit
8. MUSIC/MESSAGE PLAYBACK SYSTEM - The 8-ohm output from the power amplifier of a music or
message playback system may be routed through the D-15 to the outside speaker/mic. This signal will be muted
during D-15 talk/listen functions and fed through when the unit is in standby. Connect the music/message source's
amplified output to the "MUSIC IN" inputs per figure 4. NOTE: THIS OPTION CANNOT BE USED WITH SYSTEMS
IN THE MULTIPLE MASTER CONFIGURATION.
9. HEAVY-DUTY HANDSET (OUTSIDE) - Connect as shown in Figure 4.
10. VEHICLE DETECTION - Install the vehicle detection system per individual instructions. Set the Magnetic Loop
Detector to "Presence" mode.