Absolute Voltage Level; Absolute Peak Voltage Level; Absolute Peak Envelope Voltage Level; Absolute Level Definitions - Digital Signal Processing - ABB ETL600 Instruction Manual

ABB Switzerland Ltd
where P
5.2.3.4.

Absolute voltage level

The absolute voltage level defines by how many dB the RMS voltage
U of a signal x is greater or smaller than the reference voltage of
775 mV:
[
L dBu
u
where U
5.2.3.5.

Absolute peak voltage level

The absolute peak voltage level defines by how many dB the peak
voltage U of a signal x is greater or smaller than the reference voltage
of 775 mV:
[
L dBu
u
where U
5.2.3.6.

Absolute peak envelope voltage level

The absolute peak envelope voltage level defines by how many dB the
peak envelope voltage U of a signal x is greater or smaller than the
reference voltage of 775 mV:
[
L dBu
u
where U
5.2.4.

Absolute level definitions - digital signal processing

Within ETL600, most signal processing operations are executed by
digital signal processors (DSPs). Continuous analog signals are
represented by time sequences of sampling values. Each sampling
value X(n) is a dimensionless digit in fixed or floating point
representation.
In analogy to analog signals, we define the following levels for digital
signals:
5-4
1KHW001489-EN
(x) is given by equation (3).
PE
⎛
]
U (
⎜ ⎜
= ∗
RMS
20 log
⎝
775 mV
(x) is given by equation (4).
RMS
⎛
]
⎜ ⎜
= ∗
peak 20 log
⎝
(x) is given by equation (5).
peak
⎛
]
U
= ∗ ⎜ ⎜
PE 20 log
⎝
775
(x) is given by equation (6).
PE
November 2005
⎞
x )
⎟ ⎟
,
⎠
⎞
U ( x )
⎟ ⎟
peak
,
⎠
775 mV
⎞
( x )
⎟ ⎟
PE
,
⎠
mV
Configuration and Set-up
ETL600
(10)
(11)
(12)