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CHAPTER 1
Self-powered and compact, the UPJ-1P combines ad-
vanced loudspeaker technology with equally advanced
power capabilities. Understanding power distribution, volt-
age and current requirements, as well as electrical safety
issues, is critical to the safe operation of the UPJ-1P.
AC POWER
The UPJ-1P uses a PowerCon 3-pole AC mains system
with locking connectors to prevent accidental discon-
nection. It may also be daisy-chained by using the grey
connector (Figure 1.1) to loop units together. The blue
connector serves as the power input; to loop additional
units, simply attach a cable from the grey connector of the
rst loudspeaker to the blue connector of the second, and
so on. One looping connector is included with each UPJ-
1P. Optional assembled looping cables can be purchased
from Meyer Sound.
Figure 1.1. You can daisy-chain UPJ-1P loudspeakers using the grey
connector.
!
CAUTION: Do not loop more than four
UPJ-1Ps from the loop out connector when
connected at 115 V and not more than eight when
driven at 230 V.
!
CAUTION: Be sure to select the correct
power plug for the AC power in the area in
which you operate your UPJ-1P loudspeaker.
When AC power is applied to the UPJ-1P, its Intelligent
AC™ power supply automatically selects the correct
operating voltage, allowing it to be used internationally
without manually setting voltage switches. Intelligent AC
performs the following protective functions to compensate
for hostile conditions on the AC mains:
Suppresses high-voltage transients up to several kilo-
volts
Filters common mode and differential mode radio
frequencies (EMI)
Sustains operation temporarily during low-voltage
periods
The UPJ-1P can withstand continuous voltages up to
264 V and allows any combination of voltage to GND (that
is, neutral-line-ground or line-line-ground).
!
CAUTION: Continuous voltages higher than
264 V may damage your UPJ-1P.
Voltage Requirements
The UPJ-1P operates safely and without audio discontinu-
ity if the AC voltage stays within the operating window of
90-264 V AC, at 50 or 60 Hz.
After applying AC power, the system is muted while the
circuitry charges up and stabilizes. During the next two
seconds the following events occur:
1. The fan turns on.
2. The main power supply slowly ramps on.
3. The green On/Temp LED on the user panel lights up,
indicating that the system is enabled and ready to
pass audio signals.
!
CAUTION: If the On/Temp LED does not
illuminate or the system does not respond
to audio input after ten seconds, remove AC power
immediately. Verify that the voltage is within the
proper range. If the problem persists, please con-
tact Meyer Sound or an authorized service center.
If the voltage drops below the low boundary of its safe
operating range (brownout), the UPJ-1P loudspeaker uses
stored energy to continue functioning briey, and shuts
down only if voltage does not rise above the low bound-
ary before storage circuits are depleted. How long the
loudspeaker will continue to function during brownout
depends on the amount of voltage drop and the audio
source level during the drop.
If the voltage increases above the upper boundary of the
range, the power supply can be damaged.
NOTE: It is recommended that the supply
be operated in its rated voltage window at
least a few volts away from the extreme points.
This ensures that AC voltage variations from the
service entry – or peak voltage drops due to cable
runs – do not cause the amplier to cycle on and
off or cause damage to the power supply.
CHAPTER 1: POWER REQUIREMENTSBlue Grey