SRS动态信号分析仪、SRS SR785动态信号分析仪、100kHz双通道FFT分析仪

SRS动态信号分析仪SRS SR785动态信号分析仪100kHz双通道FFT分析仪

  • DC至102.4 kHz带宽
  • 90 dB动态范围
  • 145 dB动态范围(正弦扫频)
  • 订单跟踪
  • 20极点/20零点曲线拟合
  • 实时倍频程分析
  • 高达32兆字节的内存
  • GPIB和RS-232接口
概观
SR785双通道动态信号分析仪是一款精密、全功能信号分析仪,提供一流的性能,而价格不到竞争分析仪的一半。SR785以其前身SR780为基础,集成了新的固件和硬件,是分析机械和电气系统的理想仪器。

SR785 Specifications

Specifications apply after 30 minutes warm-up and within 2 hours of last auto-offset. Measured with 400 line resolution and anti-alias filters enabled unless stated otherwise.

Measurement Groups

GroupsFFT, Correlation, Time Histogram, Swept-Sine, Order Tracking

Frequency

Range102.4 kHz or 100 kHz (both displays have the same range)
FFT spans195.3 mHz to 102.4 kHz or 191 mHz to 100 kHz. The two displays can have different spans and start frequencies.
FFT resolution100, 200, 400 or 800 lines
Real-time bandwidth102.4 kHz (highest FFT span with continuous data acquisition and averaging)
Accuracy25 ppm from 20 °C to 40 °C

Dynamic Range

Dynamic range90 dB typical, 80 dB guaranteed (FFT and Octave). 145 dB typical (Swept-Sine). Includes spurs, harmonics, intermodulation distortion, and alias products. Excludes alias responses at extremes of span.
Harmonic distortion<-80 dB
(single tone in band)
Intermod. distortion<-80 dB
(two tones in band, each less than -6.02 dBfs)
Spurious<-80 dBfs
Alias responses<-80 dBfs
(single tone outside of span, <0 dBfs, less than 1 MHz)
Full span FFT noise floor-100 dBfs typical
(input grounded, >-30 dBV, Hanning window, 64 rms averages)
Residual DC response<-30 dBfs
(FFT with Auto-Cal on)

Amplitude Accuracy

Single channel±0.2 dB (excluding window effects)
Cross channel±0.05 dB, DC to 102.4 kHz (frequency response measurement, both inputs on the same range, rms averaged)

Phase Accuracy

Single channel±3.0 deg. relative to external TTL trigger (-50 dBfs to 0 dBfs, freq <10.24 kHz, center of frequency bin, DC coupled). For Blackman-Harris, Hanning, Flat-Top and Kaiser windows, phase is relative to a cosine wave at center of time record. For Uniform, Force and Exponential windows, phase is relative to a cosine wave at beginning of the time record.
Cross channel±0.5 deg. (DC to 51.2 kHz)
±1.0 deg. (DC to 102.4 kHz)
(frequency response measurement, both inputs on same range, vector averaged)

Signal Inputs

Number of inputs2
Full-scale input range-50 dBV (3.16 mVp) to +34 dBV (50 Vp) in 2 dB steps
Maximum input level57 Vp
Input configurationSingle-ended (A) or differential (A-B)
Input impedance1 MΩ + 50 pF
Shield to chassisFloating mode: 1 MΩ + 0.01 µF
Grounded mode: 50 Ω
(shields grounded in (A-B) mode)
Max. shield voltage4 Vp
AC coupling0.16 Hz cutoff frequency
CMRR90 dB at 1 kHz (input range <0 dBV)
80 dB at 1 kHz (input range <10 dBV)
50 dB at 1 kHz (input range ≥10 dBV)
ICP signal conditioningCurrent source: 4.8 mA
Open circuit voltage: +26 V
A-weight filterType 0 tolerance, ANSI standard S1.4-1983; 10 Hz to 25.6 kHz
Crosstalk<-145 dB below signal (input to input and source to inputs, 50 Ω receiving input source impedance)
Input noise<10 nVrms/√Hz above 200 Hz (<-160 dBVrms/√Hz)

Trigger Input

ModesFree Run, Internal, External, or External TTL
InternalLevel adjustable to ±100 % of input scale, positive or negative slope. Min. trigger level: 5 % of input range
ExternalLevel adjustable to ±5 V in 40 mV steps, positive or negative slope.
Input impedance: 1 MΩ
Max. input: ±5 V
Min. trigger amplitude: 100 mV
External TTLRequires TTL level to trigger
(low <0.7 V, high >3.0 V)
Post-triggerMeasurement record is delayed up to 100,000 samples after the trigger.
Pre-triggerMeasurement record starts up to 8000 samples prior to the trigger.

Tachometer Input

Pulses per revolution1 to 2048
RPM accuracy±50 ppm (typ.)
Tach level range±25 V, ±5 V, TTL
Tach level resolution20 mV @ ±25 V, 4 mV @ ±5 V
Max. tach input level±40 Vp
Min. tach pulse width100 ns
Max. tach pulse rate750 kHz (typ.)

Transient Capture

ModeContinuous data recording
Maximum rate262,144 samples/s for both inputs
Maximum capture length2 Msamples (single input)
8 Msamples with optional memory

八度分析

StandardsConforms to ANSI standard S1.11- 1986, Order 3, Type 1-D
Frequency range(Band centers)
Single channel
1/1 Octave     0.125 Hz to 32 kHz
1/3 Octave     0.100 Hz to 40 kHz
1/12 Octave   0.091 Hz to 12.3 kHz
Two channels
1/1 Octave     0.125 Hz to 16 kHz
1/3 Octave     0.100 Hz to 20 kHz
1/12 Octave   0.091 Hz to 6.17 kHz
Accuracy<0.2 dB (1 second stable average, single tone at band center)
Dynamic range80 dB (1/3 Octave, 2 second stable average) per ANSI S1.11-1986
Sound levelImpulse, Peak, Fast, Slow and L情商 per
ANSI S1.4-1983 Type 0 and IEC 651-1979 Type 0

订单跟踪

Delta order0.0075 to 1
Resolutionup to 400 lines
Amplitude accuracy±1 dB (typ.)
显示Order map (mag. and phase), order track (mag. and phase), orbit

曲线拟合和合成

Type20 poles/20 zeros curve fit (non-iterative rational fraction)
Order selectionAuto or manual
Output formatPole-zero, polynomial, pole-residue

Source Output

Amplitude range0.1 mVp to 5 Vp
Amplitude resolution0.1 mVp
DC offset<10.0 mV (typ.)
Offset adjust±5 VDC (sine, two-tone, swept-sine)
Output impedance<5 Ω, ±100 mA peak output current
Sine Source
Amplitude accuracy±1 % of setting, 0 Hz to 102.4 kHz,
0.1 Vp to 5 Vp into High-Z load
Harmonics, sub-harm.
& spurious signals
0.1 Vp to 5 Vp
<-80 dBc (fundamental <30 kHz)
<-75 dBc (fundamental <102 kHz)
Two-Tone Source
Amplitude accuracy±1 % of setting, 0 Hz to 102.4 kHz,
0.1 Vp to 5 Vp into High-Z load
Harmonics, sub-harm.<-80 dBc, 0.1 Vp to 2.5 Vp
White Noise Source
Time RecordContinuous or burst
BandwidthDC to 102.4 kHz or limited to span
Flatness<0.25 dBpp (typ.), 5000 rms averages (<1.0 dBpp (max.))
Pink Noise Source
BandwidthDC to 102.4 kHz
Flatness<2.0 dBpp, 20 Hz to 20 kHz (measured using averaged 1/3 Octave Analysis)
Chirp Source
Time recordContinuous or Burst
输出Sine sweep across the FFT span
Flatness±0.25 dB (1.0 Vp)
Swept-Sine Source
Auto functionsSource Level, Input Range and Frequency Resolution
Dynamic range145 dB
Arbitrary Source
Amplitude range±5 V
Record length2 Msamples (playback from arbitrary waveform memory or capture buffer). Variable output sample rate.

General

InterfacesIEEE-488.2, RS-232 and Printer interfaces standard. All instrument functions can be controlled through computer interfaces. A PC (XT) keyboard input is provided for additional flexibility.
HardcopyPrint to dot matrix and PCL compatible printers. Plot to HP-GL or postscript plotters. Print/plot to RS-232 or IEEE-488.2 interfaces or to disk file. Additional file formats include GIF, PCX and EPS.
Data storageUSB drive
Preamp powerPower connector for SRS preamps
Power70 W, 100/120/220/240 VAC, 50/60 Hz