Meyer Sound UPQ-D Series, Operating Instructions Manual

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CHAPTER 2: POWER REQUIREMENTS
The UPQ-D Series loudspeakers combine advanced
loudspeaker technology with equally advanced power
capabilities. Understanding power distribution, voltage and
current requirements, and electrical safety guidelines is critical
for the safe operation of the UPQ-D Series loudspeakers.
AC POWER DISTRIBUTION
All components in an audio system (self-powered
loudspeakers, mixing consoles, and processors) must be
properly connected to an AC power distribution system,
ensuring that AC line polarity is preserved and that all
grounding points are connected to a single node or common
point using the same cable gauge (or larger) as the neutral and
line cables.
CAUTION: Make sure the voltage received by
the UPQ-D Series loudspeakers remain within
their 90–264 V AC operating range. In addition, the
ground line must always be used for safety reasons and
the line-to-ground voltage should never exceed
250 V AC (typically 120 V AC from line to ground).
CAUTION: Before applying AC power to any
Meyer Sound self-powered loudspeaker, make
sure that the voltage potential difference between the
neutral and earth-ground lines is less than 5 V AC when
using single-phase AC wiring.
NOTE: Improper grounding of connections
between loudspeakers and the rest of the audio
system may produce noise or hum, or cause serious
damage to the input and output stages of the system’s
electronic components.
120 V AC, 3-Phase Wye System (Single Line)
Line-Neutral-Earth/Ground
Figure 3 illustrates a basic 120 V AC, 3-phase Wye distribution
system with the loudspeaker load distributed across all three
phases and with each loudspeaker connected to a single line
and common neutral and earth/ground lines. This system
delivers 120 V AC to each loudspeaker.
120 V AC, 3-Phase Wye System (Two Lines)
Line-Line-Earth/Ground
Figure 4 illustrates a 120 V AC, 3-phase Wye distribution
system with each loudspeaker connected to two lines and a
common earth/ground line. This configuration is possible
because the UPQ-D Series tolerate elevated voltages from the
ground line and does not require a neutral line. This system
delivers 208 V AC to each loudspeaker.
TIP: The 120 V AC, 3-phase Wye system with two
lines is recommended because it allows
loudspeakers to draw less current than with single-line
systems, thereby reducing voltage drop due to cable
resistance. It also excludes the potential of varying
ground to neutral voltages producing an audible hum.
!
!
Figure 3: 120 V AC, 3-Phase Wye System (Single Line to Loudspeakers)
Figure 4: 120 V AC, 3-Phase Wye System (Two Lines to Loudspeakers)
Neutral
Earth/Ground
Line 1 (120 V AC)
Line 3 (120 V AC)
Line 2 (120 V AC)
Loudspeaker
(120 V AC)
Loudspeaker
(120 V AC)
Loudspeaker
(120 V AC)
Neutral
Earth/Ground
Loudspeaker
(208 V AC)
Loudspeaker
(208 V AC)
Loudspeaker
(208 V AC)
Line 1 (120 V AC)
Line 3 (120 V AC)
Line 2 (120 V AC)