L-ACOUSTICS LA 24 MANUAL Version 2.2
17/11/08 20
•
SAFETY APPROVALS
L-ACOUSTICS amplifiers are designed to meet
IEC65
, a stringent electrical safety approval
from the
International Electro-technical Commission.
The
IEC65
standard is recognized
world-wide with most countries having an equivalent.
EMC approvals
EMC stands for Electro Magnetic Compatibility. This implies that the equipment should have
low emission of radio frequencies, directly radiated as electromagnetic fields in the air and as
conducted from the cables connected to the unit. The amplifier should also be able to handle
electromagnetic fields, high voltage flashes, and radio interference coming into the unit via the
air or cables.
Emission
The regulations now cover the frequency range from 150 kHz to 300 MHz. The maximum
level radiated from a unit has to be below 100
µ
V, ( 0.0001 V ).
Immunity
The equipment should be able to handle three different types of interference:
•
Electrostatic discharges of up to 8 kV, hitting the chassis or cables.
•
Transients and bursts up to 1 kV, conducted through the cables to the unit.
Electromagnetic fields up to 3 V/m, radiated on the unit and cables in the frequency range of
27 - 500 MHz.
We have extended the tests in two cases and chosen a standard used for heavy industrial
situations. First, we have tested conducted disturbances in the frequency range 150 kHz - 80
MHz, by injecting 3V amplitude modulated (80%) signals into all the cables (inputs, outputs
and mains). This covers noise from AM transmitters, which are still in use in some areas.
Secondly, we have extended the range for electromagnetic fields to 26 - 1000 MHz, with a
level of 6 V/m and 80% AM modulated.
In the range 895 - 905 MHz, we test with a field strength of 35 V/m and 100% pulse
modulation. This emulates the signals from a mobile phone close to the unit. In all cases the
noise plus distortion is below 1% at normal operating level (normal operating level is 1/8 of
full power or -9 dB under clip point according to IEC 65).
EMC-declaration
This audio power amplifier conforms with the EMC-directive 89/336/EEC and relates to the
following standards:
EN 55013:1990
EN 50 082-1
IEC 801-2, ed.1(1984)
IEC 801-3, ed.1(1988)
IEC 801-4, ed.1(1984)
SS-ENV 50 141 ed.1 (1994)
