Publicité
Les langues disponibles
Les langues disponibles
Instructions 2688
Usage
Type 2688 converts the high impedance output of piezoelectric transducers into the low impedance signal required
for nuclear vibration monitoring applications. The 2688 is designed for use in radiation areas.
The Type 2688 has a differential input which improves the signal/noise ratio in strong electromagnetic fields when
used together with balanced accelerometers, such as B&K Vibro Type 8315 and Type 8324.
If single-ended accelerometers are used the "-" input terminal of the charge amplifier must be connected to the
ground terminal.
To protect the Type 2688 from harsh environmental conditions, such as EMC, humidity and vibration, it must be
mounted in an electrically shielded junction box in conformity with IP 65, as available from Brüel & Kjær Vibro. Type
2688 may be supplied in a number of versions when other amplification factors or filtering ranges are required.
Technical Data
Balanced Charge Input
Sensitivity
Frequency range
Max. input signal
High-Pass filter
Common mode rejection
Noise
Source impedance
Effects of source impedance
on Low frequency response
Connections
Output
Min. voltage devitation
Output impedance
DC offset
Short circuit time
Drive capacity
Connections
©Brüel & Kjaer Vibro GmbH / 2688 DEF / 28.8.18
Technical specifications subject to change!
1 mV/pC, ±2% at 80 Hz
1 Hz to 100 kHz ±1 dB
8 nC
nd
2
order, -3 dB @ 0.48 Hz
> 30 dB (1 Hz to 50 kHz)
-3
< 40 x 10
pC
referred to input terminated with 1 - 4 nF,
2 Hz to 50 kHz
> 50 M
10 M ---> 2 dB peak @ 0.8 Hz
4 M ---> 5 dB peak @ 0.8 Hz
2 M ---> 8 dB peak @ 0.9 Hz
Screw terminals
-2.5 V to -17.5 V unloaded
2 x 5
-10 V, + 2%
Infinite
Min. 13 mA peak
Screw terminals
| Usage
EN
l
page 3
C105120.001 / V03
Publicité
