EAW DSA250 & DSA230 User Manual

Page 18

5.1.5

DAISY CHAINING COMPUTER AND AUDIO SIGNALS BET WEEN CLUSTERS

Any distance (within EIA-485 limitations) between clusters:
2-conductor shielded cable

Audio A, Audio B, and EIA-485

Connect in parallel to the incoming signal cables on one loudspeaker
in the first cluster and connect to the same signal ports on one
loudspeaker in the next cluster. Use the supplied 3-pin Phoenix
Contact terminal plugs.

Recommended Conductor Gauge:
24 AWG to 18 AWG / 0.2 mm to 1 mm

5 . 1 . 6

E I A - 4 8 5 T E R M I N AT E S W I T C H

EIA-485 termination has special requirements and limitations. See
Appendix 8.3 for details.

Single Cluster:

Set the EIA-485 Terminate Switch on the loudspeaker
(connected via the Phoenix connector) to “ON”.

Multiple Clusters:

Set the EIA-485 Terminate Switch to “ON” ONLY on the
loudspeaker (connected via the Phoenix connector) at the end of the
EIA-485 cable run furthest from the computer. Set all other Terminate
Switches to “OFF”.

CAUTION: Engaging the EIA-485 Terminate Switch on more than
one loudspeaker on the EIA-485 cable run can cause intermittent
or non-existent communications.

5 . 2

C o b r a N e t ™ N e t w o r k C o n n e c t i o n s

This section provides details about using the optional CobraNet™
technology for distribution of audio and computer control signals.

5 . 2 . 1

D E S C R I P T I O N

CobraNet™ is a combination software, hardware, and network protocol
that replaces the audio and computer connections described in Section
5.1. Digitized audio and computer control is distributed by a CAT-5
(or better) cable to each loudspeaker. The network infrastructure must
be designed using standard IEEE 802.3u 100BASE-T Fast Ethernet
hardware. The network will not function properly using 10BASE-T
technology.

5 . 2 . 2 C O B R A N E T ™ I S U S U A L LY D E S I R A B L E T O U S E W H E N :

· A star cable configuration is easier to implement for multiple loudspeakers

· A high degree of noise immunity is needed for the audio
· Future system expansion is likely
· Long cable runs that permit fiber optic cabling
· Other CobraNet™-capable products are used in the same installation
· The number of loudspeakers and clusters exceeds 32
· The audio source(s) have digital outputs

EIA-485

AUDIO A

AUDIO B

Figure 5.1.5 Linking > 2 ft / 0.6 m

EIA-485 TERMINATE SWITCH

EIA-485

TERMIN

ATE

AUDIO

GROUND

LIFT

OFF

LIFT

RS-232

OR USB

TO EIA-485

CONVERTER

DSA
CLUSTERS

TERMINATE
SWITCH "OFF"

TERMINATE
SWITCH "ON"

Figure 5.1.6b EIA-485 Network Diagram

Figure 5.1.6a EIA-485 Terminate Switch