Operating Manual - nX, nXe, and nXp Power Amplifiers
10
3 nX AMPLIFIER PROTECTION
Power-On Delay
-
All models have a three second warm-up delay to prevent excessive in-rush current when first powered on or
awakened from sleep. nXe and nXp models additionally offer programmable Power-On Delay of up to 25 seconds
Thermal Protection
-
Cooling fans are continuously variable, reaching their maximum speed when an amplifier channel reaches
80% of it's safe operating temperature, also turning on theTemp LED. At 90%, the Protect LED turns on to indicate countermea
-
sures have been applied to attenuate the input signal to the overheating channel. A Temp LED turns on dim at first, then increases
in brightness as the amp channel approaches maximum safe temperature. 100% critical temperature will shut down the amplifier.
Overpower Protection
-
To protect internal components against overpower conditions, a protection scheme in each output stage
reduces audio output power until the fault condition is no longer present.
Output DC and Rail Fault Protection
– Output DC on any channel will trigger the Protect LED and mute that channel. Voltage
rail irregularities such as power supply pumping are also detected and compensated for in real time as the amp runs.
AC Mains
-
If the AC Mains line voltage exceeds or falls below the specified
, the amplifier will temporarily
shut down. It will automatically restart as soon as the AC line voltage returns to the specified range.
For details on these and other amplifier protection schemes, plus their LED codes, refer to
in section 14.
4 nX FRONT PANEL FEATURES (all models)
4.1 Mounting Holes
– For mounting to a 19" equipment rack.
4.2 Air Vents
– Cool air enters in through the amplifier sides and is vented out the front.
4.3 Reset/Sleep Mode/Disable Switch
– This recessed switch is used to reset the amplifier to its default factory settings,
however it will not erase amplifier presets. Protea
ne
software must be used to erase amplifier presets (
). This switch is
also used to set sleep mode and front panel disable status (see below).
To reset amplifier settings, routing, networking, and security (not presets) to original factory defaults, use a plastic paper clip
or equivalent to press and hold the switch
during power up
until all channel LEDs sequence
from bottom to the top. Release the switch before the LED sequence is complete to cancel
the process. Upon completion, all LEDs turn off and the amplifier resumes normal operation.
Setting Sleep and Front Panel Disable Mode -
The factory reset switch is also used to select
one of four sleep and front-panel-control-disable modes as illustrated to the right. The default
status is Sleep and Disable OFF (
Mode 1
). To advance to the next mode, press and hold this
switch when the amplifier is fully on, and the four mode combinations will cycle and repeat
.
To select a mode, simply release the switch when the desired mode is displayed.
The Disable LED is lit any time the front panel controls are disabled, either by selecting disable
mode from this switch or using software control.
The sleep LED turns on during the mode-select cycle whenever sleep mode is enabled, but turns
back off as soon as the switch is released, remaining off unless the amp actually goes to sleep.
The current sleep mode status can be displayed when the amp is fully on by quickly pressing
and releasing the reset switch. If the sleep LED lights, sleep mode is active.
