Protection - B-52 US-5000 Owner's Manual

and contact an authorized B-52 Service Center.
There are rare instances when the circuit breaker acts
on a constant heavy overload with a very low imped-
ance load connected to amplifier, protecting your
amplifier against such improper usage. In such cases
you need to check and correct your load (loudspeak-
ers) to provide for the proper load impedance, and/
or reduce output signal.
10. AC INPUT
US-5000/6000 amplifiers are factory preconfigured
for either 120V or 230V AC voltage, based on where
they are sold. 120V models are fitted with a fixed heavy
AWG12 cord to provide high current consumption with-
out losses and deliver power peaks without sags.
NOTe: US-6000 120V amplifier's cord is
terminated with 20A NEMA plug and
must be connected to proper 20A rated
AC line. The pins on this 20A rated plug are
oriented differently than on a standard 15A

PROTECTION

US-Series amplifiers feature comprehensive protection
circuitry that protects both the loudspeakers and the
electronics from malfunctioning. The protection is non-
intrusive, sonically transparent and does not affect the
sound unless there are extreme conditions that acti-
vate the protection circuitry.
The PROTECT LEDs on the front panel illuminate when
the protection is active during the power-up sequence,
when thermal protection is activated, or when there is
a malfunction. When the PROTECT LEDs are ON, the
amplifier's outputs are muted.
INITIAl POWeR-UP: The protection circuitry will
activate for about two to three seconds from the time
you turn ON the amplifier. The speaker outputs are
muted during this period. If the amplifier is operating
normally, the protection circuitry will deactivate and
the amplifier will switch to operation mode.
NOTe: It is normal for the PROTECT LED to fade
gradually after the amplifier is turned OFF.
TheRMAl PROTeCTION: Excessive heat-sink tem-
peratures will engage the thermal protection circuitry
to avoid damage to your amplifier. The speaker
output will mute and the PROTECT LED will illuminate.
Thermal protection only engages on the channel
THE BEAUTY OF POWER
11. led STRIPS SWITCh
The LED STRIPS switch allows you to turn blue LED
strips lights on front panel ON, OFF or dim them half-
way. This gives you flexibility for installations where
you may want to control lights.
which has the overheating heatsink. The thermal pro-
tection will automatically restore to normal operation
mode automatically once the heatsink temperature
drops to a safe level.
B-52 US Series Professional Power Amplifiers - Instruction Manual
US SERIES AMPLIFIERS
rated plug, and will not fit into standard 15A
rated wall AC outlet.
WARNINg: Never cut off 20A rated AC plug
to replace with different plug; it will represent
safety hazard.
NOTe: 230V models are equipped with a
standard IEC connector on rear panel and
supplied with heavy gauge AC power cord
appropriate with country of sale.
NOTe: Never disconnect the EARTH pin from
the AC connection. It will defeat safety measures
used in your power amplifier and void the
warranty.
NOTe: If the thermal protection constantly
activates, check the impedance of your loud-
speakers and the condition of the air filters on
front of the amplifier. The loudspeakers
impedance must not be lower than what is
specified in this manual for 2-channel and
BRIDGE operation. 8 Ohms and 4 Ohms speaker
loads per channel (8 Ohms and 16 Ohms in
BRIDGE mode) should not trigger the thermal
protection circuitry if the air access is not
blocked and the air filters are clean. 2 Ohms
speaker loads per channel (4 Ohms in BRIDGE
mode) can cause the thermal protection circuitry
to activate occasionally. If this occurs, decrease
the signal level and consider reconnecting the
speaker connections to reduce the load on the
amplifier (for example, do not connect too many
speakers in parallel to the same channel).
NOTe: Make sure there is adequate air access
to the amplifier. Do not block the air vents on
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