27
Chapter 6
Specifications
Specifications
−
Types 2694 A, B, C, D
DELTATRON INPUT/VOLTAGE INPUT
Connector:
Channel 1 to 15
−
BNC
Channel 16
−
BNT (CCLD, voltage or tacho)
Grounding: Single-ended or floating
Input Impedance (typical):
1 M
Ω //
300 pF (Voltage mode)
100 k
Ω //
300 pF (DeltaTron mode)
Maximum Input; Differential Voltage:
≤
20 V
pp
(without clipping)
Common mode:
≤
±
5 V
Input Protection:
±
35 V
p
Differential Voltage (non-
destructive);
±
5 V
p
Common mode Voltage (non-destructive)
Common Mode Rejection Ratio: >60 dB (up to
1 kHz) @
−
10 dB typical; >70 dB (up to 1 kHz) @ 0 dB
to +40 dB typical
Amplifier Gain:
−
10 dB*; 0 dB;
10 dB*; 20 dB; 30 dB*; 40 dB*
Transducer Supply
DeltaTron Current: 6 mA
±
15%
DeltaTron Voltage: 25 V
±
10%
Cable Length (in TEDS-recognition mode):
≥
100 m
Tacho Probe Supply (channel 16 only(typical)): +8 V
DC at BNT inner shield (short-circuit protected)
Frequency Range (
−
1 dB/
−
10%): 0.1 Hz to 50 kHz
High-pass Filter (
−
1 dB): 0.1 Hz* and 1 Hz
Low-pass Filter (
−
1 dB): 50 kHz
Harmonic Distortion @ 1 kHz, V
out
< 5 Vrms: <
0.01%,
typically < 0.001%
Rise Time: < 4 µs (50 kHz bandwidth)
Channel-to-channel Phase Match (calculated
values):
≥
1
×
f
low
≤
2 degrees
≥
10
×
f
low
≤
0.25 degrees
≥
100
×
f
low
≤
0.025 degrees
Flexible Filter Configuration
−
Built-in filters:
High-pass filters (versions A, C and D)
There are two standard, built-in, high-pass filters
at the input, 0.1 Hz and 1 Hz @
−
1 dB (40 dB/decade)
High-pass filters (version B)
1 Hz @
−
1 dB (20 dB/decade)
Low-pass filters
The upper frequency limit is set at the factory to
50 kHz @
−
1 dB (20 dB/decade)
Optional Filters*
In addition to the built-in, high-pass filters, a
number of optional standard filters can be
installed, for example, A-, B-, C-, and D- weighting
(complies with IEC 651 Type 0) and single/double
integration
Inherent Noise (referred to input, gain
≥
20 dB):
≤
3 µV A-weighting, typical value < 1.8 µV;
≤
5 µV lin. 2 Hz to 22.4 kHz; typical value < 2.8 µV
lin. 2 Hz to 22.4 kHz
Typical Broadband Output Noise: < 1.8
µ
V A-
weighted; < 2.8
µ
V lin. 2 Hz to 22.4 kHz
0 dB
4.6 µV rms
3.0 µV rms
10 dB*
9.0 µV rms
6.0 µV rms
20 dB
22 µV rms
14.5 µV rms
30 dB*
65 µV rms
44.0 µV rms
40 dB*
200 µV rms
150 µV rms
Dynamic Range (Typical): > 120 dB 22.4 kHz BW @
0 dB gain;
> 125 dB A-weighting @ 0 dB gain (Max. output
voltage rms/ broadband output noise)
*Not available with version 2694 B
BE164411.book Page 27 Friday, May 18, 2001 11:51 AM
