Signal Ground Connection; Protection Features - Peavey IA 200 Owner's Manual

THE AC MAINS AND SPEAKER LOAD MODULE IS NOT REMOVABLE. DO NOT ATTEMPT TO
REPLACE OR REMOVE IT!
This module can only be serviced by a Peavey Electronics-authorized technician. Please con-
sult your dealer or Peavey Electronics representative for assistance. User-inflicted damage to
this module will invalidate your warranty.

SIGNAL GROUND CONNECTION

Connections at the input connector permit the audio signal ground to be connected or lifted from the
chassis ground. Whenever possible, the shield of the signal source connecting cable should connect
to the chassis ground. In some cases, however, particularly if an amplifier is being installed in an
existing system, this may result in a ground loop. If this happens, connect the shield to the signal
ground only. The chassis ground also connects to the AC ground internally. If the cable shield is
connected to the signal ground only, it will be clamped to +/- 0.6V above or below chassis/AC
ground.

PROTECTION FEATURES

The IA Series incorporates protection features derived from Peavey's extensive experience with
reliability. The amplifiers are ruggedly built from high quality components and feature comprehensive
protection circuits to protect your amplifier from those "real world" occurrences.
CLIP LIMITING
At the amplifier's full power, or clipping point, the channel gain will automatically be reduced, guard-
ing the loudspeakers against damaging high power and continuous square waves that would other-
wise be produced. This is indicated by illumination of the Clip LED. Normal program transients will
not trigger Clip Limiting; only steady or excessive clipping will. Operation is virtually transparent in
use and full signal bandwidth is maintained.
LOAD FAULT CORRECTION
™
LFC (Load Fault Correction
to allow the amplifier to operate at a safe level into an abnormal load. This is indicated by illumina-
tion of the LFC LED. Moderate activation of LFC is inaudible in normal use. In addition, if extreme
low impedance or a short circuit is encountered during high signal level conditions, the amplifier's
output relay will open.
INITIALIZATION PROTECTION
™
IP operates every time the amplifier is turned on, or after a protect condition. During turn-on,
the amplifier goes into protect mode and leaves the speaker load disconnected until the amplifier
determines that the operating status is normal. The IP
the initial turn-on or protect operation. After relay release, channel gain gradually increases to the
attenuator setting to avoid unnecessary stress on the loudspeakers.
THERMAL PROTECTION
If the heatsink temperature or power transformer reaches an abnormally high temperature, the
amplifier will protect itself by disconnecting the speaker load until the amplifier returns to a normal
temperature. During this time, the Protect LED will illuminate, and the cooling fan will operate at
maximum speed.
SHORT CIRCUIT
If an output is shorted, the LFC
™
amplifier. The LFC
channel gain to a safe level for the load. In extreme or severe conditions, the speaker relays will
disconnect the load and initiate a power-on start-up sequence.
DC VOLTAGE PROTECTION
If an amplifier channel detects DC voltage or subsonic signals at its output terminals, the speaker
relay will immediately open to prevent loudspeaker damage. The Protect LEDs will light.
™
™
) is an innovative circuit that will instantaneously reduce channel gain
™ ™
(IP )
™
, speaker relay and thermal circuits will automatically protect the
circuit senses the short circuit as an abnormal load condition and reduces the
™
circuit attenuates the signal during
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