BRUEL & KJAER 2663, Technical Documentation Manual

Page: 35 / 54

Chapter 3 — Operating Characteristics
Phase Response
Preamplifiers Types 2663 and 2663 B
User Manual
Brüel & Kjær
28
For acceleration measurement, the overall system sensitivity is as follows:
= ×
System Accelerometer Type 2663
Sensitivity Sensitivity Sensitivity
Determination of system sensitivity is thus simplified as the charge sensitivity of the
accelerometer used, is that stated on its calibration chart. Note that the very high
input capacitance of the preamplifiers makes the influence of input cable shunt ca-
pacitance on the sensitivity of the system insignificant.
3.4 Phase Response
The typical phase response of the the preamplifiers for the preset frequency range
(0.5 Hz to 33 kHz) is shown in
Fig.3.8 . Note that changing the upper or lower limiting-
frequency will alter the phase characteristics accordingly.
Fig.3.8 Phase response of Type 2663 with 2 nF input load
mV
ms
2 –
-------------
pC
ms
2 –
-------------
mV
pC
---------
10 Hz 100 Hz
1 kHz
10 kHz
40
o
20
o
0
o
-20
o
-40
o
-60
o
-80
o
-100
o
-120
o
-140
o
20 Hz 50 Hz 200 Hz
500 Hz
2 kHz
5 kHz
20 kHz 50 kHz
1 Hz
2 Hz
5 Hz
100 kHz
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