General
The model 7310 Noise Rejecting Voltmeter is a flexible instrument designed to offer the engineer or scientist the ability to measure signals that are accompanied by unwanted noise or interference.
The unit can best be visualized as a digital filter implemented using the latest digital signal processing (DSP) techniques followed by a true rms to DC converter and digital meter. The filter can be configured as a bandpass stage with adjustable center frequency and Q-factor as a low-pass filter with adjustable cut-off frequency or bypassed for broadband measurements. A separate analog line-frequency rejection filter adds yet further filtering flexibility.
Input signals may be from single-ended or differential voltage or single-ended current sources. After amplification but prior to the digital filter the discrete Fourier transform of the applied signal and noise can be calculated and displayed graphically on screen. This spectral display mode can then be used to adjust the filter controls so that the instrument is only measuring the required signal.
The model 7310 is very easy to use. All instrument controls are adjusted using soft-touch front panel push-buttons with the present settings and measured outputs being displayed on the centrally located cold fluorescent backlit dot-matrix LCD. Numeric outputs are shown in volts or amps rms or in decibels with respect to a preset reference level and maximum and minimum level indicators indicate the highest and lowest amplitudes since the last reset operation. A large-digits display mode is particularly convenient when using the instrument for a single type of test giving a very easy to read display.
A LabVIEW driver downloadable from this site supports all instrument functions.
Capable of measuring signals from DC to 60 kHz the instrument is ideal for many audio mechanical vibrational and electronic measurements.
| Measurement Modes | ||
| AC RMS voltage or current | ||
| AC RMS voltage or current with respect to preset 0dB level | ||
| Average DC voltage or current | ||
| Average DC voltage or current with respect to preset 0dB level | ||
| Minimum signal since last reset operation | ||
| Maximum signal since last reset operation | ||
| Displays | Cold fluorescent backlit 64 ?/font> 240 pixel dot-matrix LCD with the following displays: | |
| Main Display | Principal instrument controls and digital and analog bar-graph displays of measured signals | |
| Spectral Display | Spectral density of input signal over selected frequency range with a linear or logarithmic power scale | |
| Large Digits Display | One selected instrument output shown in large digital format | |
| Graphical Display | Display of one or two selected instrument outputs or auxiliary inputs as a function of time | |
| Other Menus | Menu system with dynamic key function allocation allowing access to all instrument controls. On-screen context sensitive help. | |
| Signal Channel | ||
| Voltage Inputs | ||
| Modes | A only B only or Differential (A-B) | |
| Full-scale Sensitivity Range | AC measurement mode: 10 to 1 V rms in a 1-2-5 sequence; DC measurement mode 1 mV to 1 V in a 1-2-5 sequence | |
| Input Impedance | 10 MW // 30 pF | |
| Maximum Safe Input | 30 V pk-pk | |
| Voltage Noise | 5 nV/?/font> Hz at 1 kHz | |
| CMRR | > 100 dB at 1 kHz degrading by 6 dB/octave | |
| Frequency Response | AC measurement mode: 300 mHz to 60 kHz | |
| Gain Accuracy | 0.2 % typ 0.6% max.(full bandwidth) | |
| Distortion | -90 dB THD (60 dB signal channel gain 1 kHz | |
| Grounding | BNC shields can be grounded or floated via 1 kW to ground | |
| Current Inputs | ||
| Full-scale Sensitivity | 10 pA to 1 in a 1-2-5 sequence | |
| Input Impedance | < 250 W at 1 kHz | |
| Maximum Safe Input | 30 V pk-pk | |
| Voltage Noise | 130 fA/?/font> Hz at 1 kHz | |
| Frequency Response | AC measurement mode: 300 mHz to 60 kHz | |
| Gain Accuracy | ?/font> 0.6 % typ | |
| Grounding | BNC shields can be grounded or floated via 1 kW to ground | |
| Line Filter | ||
| Type | Two cascaded analog second-order frequency rejection (notch) stages set to center frequencies equal to the line frequency (F) and twice the line frequency respectively | |
| Settings | F 2F F&2F or disabled | |
| Frequency Rejection | Each stage gives greater than 34 dB attenuation at ? % of center frequency | |
| Main ADC | ||
| Type | 18 bit ADC | |
| Sampling Rate | 200 kHz | |
| Digital Filter | ||
| Type | Two cascaded second order digital filter stages giving an overall fourth-order response. | |
| Settings | Bandpass Low-pass or Flat | |
| Controls | ||
| Bandpass | Center Frequency: 1.000 Hz to 60 kHz; Q-factor: 2 to 100 in a 1-2-5 sequence | |
| Low-pass | -3dB Frequency: 10 Hz to 28 kHz | |
| Flat | None | |
| True RMS - DC Converter & Output Processor | ||
| De | True RMS algorithm implemented using a DSP running at a 200 kHz sampling rate and managed by a powerful 68000-series host processor | |
| Output Zero Stability | Digital Outputs: No zero drift on all settings; Displays: No zero drift on all settings: Analog Outputs: < 5 ppm/ | |
| Output Smoothing | Time Constant: 5 ms to 10 s in a 1-2-5 sequence; Slope: 6 or 12 dB/octave | |
| Offset | Auto and Manual offset of up to ?00 % of the full-scale sensitivity range applied prior to the RMS-DC conversion | |
| Auxiliary Inputs | ||
| ADC 1 and 2 | ||
| Maximum Input | ?0 V | |
| Resolution | 1 mV | |
| Accuracy | ?5 mV at full-scale | |
| Input Impedance | 1 MW // 30 pF | |
| Sample Rate | ADC 1 only: 40 kHz max; ADC 1 and 2: 13 kHz max | |
| Trigger Mode | Internal External or burst | |
| Trigger input | TTL compatible | |
| Outputs | ||
| Signal Monitor | ||
| Amplitude | ?0 V FS | |
| Impedance | 1 kW | |
| Filter Output | ||
| Function | Representation of input signal after filtering by digital filter stage | |
| Amplitude | ?0 V ( = ?/font> 5.0 V in bandpass mode) | |
| Update Rate | 200 kHz | |
| Output Bandwidth (-3dB) | 25 kHz | |
| Output Impedance | 1 kW | |
| DC Output | ||
| Function | OUTPUT dB OUTPUT RATIO LOG RATIO or USER EQUATION | |
| Amplitude | ?0 V full scale | |
| Impedance | 1 kW | |
| Update Rate | 200 Hz | |
| Auxiliary D/A Output 1 2 3 & 4 | ||
| Max Output | ?0 V | |
| Resolution | 1 mV | |
| Impedance | 1 kW | |
| 8-bit Digital Output | 8 TTL compatible lines that can be independently set high or low to activate external equipment | |
| Power - Low Voltage | ?5 V at 100 mA rear panel DIN connector for powering SIGNAL RECOVERY preamplifiers | |
| Data Storage | ||
| Data Buffer | ||
| Size | 32k 16 and 32-bit data points may be organized as 1?/font> 32k 2?/font> 16k 3?/font> 10.6k 4?/font> 8k etc. | |
| Max Storage Rate | From NRV: up to 800 16-bit values per second; From ADC1: up to 40000 16-bit values per second | |
| Interfaces | RS232 IEEE-488. A second RS232 port is provided to allow "daisy-chain" connection and control of up to 16 units from a single RS232 computer port. | |
| Power Requirements | ||
| Voltage | 110/120/220/240 VAC | |
| Frequency | 50/60 Hz | |
| Power | < 40 VA | |
| Dimensions | ||
| Width | 350 mm (13.75") | |
| Depth | 415 mm (16.5 ") | |
| Height | ||
| with feet | 105 mm (4.1 ") | |
| without feet | 91 mm (3.6 ") | |
| Weight | 8.1 kg (18 lbs) | |
 | 资料下载(10.5M)： |
| 美国SignalRecovery(原名EG&G)公司微弱信号检测系列产品 |
