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PLM Series Operation Manual rev 1.1.3
9. Front Panel Interface
Network/
Frame
Status
Module A
Input
Module B
Input
Not Used
Channel
Output 1
Channel
Output 2
Channel
Output 3
Channel
Output 4
1
2
3
4
5
6
7
8
Figure 9.10a: Front panel soft function buttons
in fault/warning mode
Clip indication
The front panel LEDs also indicate input and output clip or pre-clip conditions that can occur within the PLM.
Input Clip
Input clipping is monitored at two positions in the signal chain:
The analog input stage: If the input signal exceeds 12 dBu or +26 dBu (according to analog
▸
sensitivity setting), a clip indication will be given. Does not apply if digital or Dante inputs selected.
Lake processor Module inputs: If the signal level at this point e25 dBu, a clip indication will be
▸
given.
The clip indication is given by the associated Module LED flashing red. In addition, the warning
INPUT CLIP
is displayed on the screen. If a second clip within 400 ms is detected, the LED will remain on for a longer
period.
Figure 9.10b: Input clip
LED and on-screen
warning
Output clip
All output channels are monitored by a suite of protection circuits that include a Current Peak Limiter (CPL)
and an Inter-Sample Voltage Peak Limiter (ISVPL). See section 7.3 – Amplifier and Load Protection Systems
for further information. If the CPL protection device is active, or a voltage clip occurs, then the appropriate
Channel Output LED will flash red. In addition, a corresponding text warning will also be displayed on the
screen.
The relationship between LEDs and inputs and
outputs is maintained in MENU mode. It is
important to remember that the LEDs often operate
independently of the function of the soft function
buttons.
