Manuale d’uso / di manutenzione del prodotto SCC-LP02 del fabbricante National Instruments
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USER GUIDE SCC-LP Series Lowpass Filter Modules The SCC-LP Series lowpass filter mod ules contain fourth-order Butterworth filter circ uitry. They accept two di fferential input signals within a ± 10 V range. A differential ampl ifier attenuates each signal by a factor of two.
SCC-LP Series Lowpass Filter Module s User Guide 2 ni.com When symbol is marked on a product, it denotes a warning advising you to take precautions to av oid electrical shock. When symbol is marked on a product, it denotes a component that may be hot.
© National Instruments Cor poration 3 SCC-LP Series Lowpass Filter Modul es User Guide What Y ou Need to Get Started To set up and use the SCC-LP XX , you need the following items: ❑ SC-2345/2350 w.
SCC-LP Series Lowpass Filter Module s User Guide 4 ni.com Device Specific Information Note For general SCC module installation and signal connection information, and information about the SC-2350 carrier , refer to the SCC Quick Start Guide , av ailable for do wnload at ni.
© National Instruments Cor poration 5 SCC-LP Series Lowpass Filter Modul es User Guide The signal source can be floating or ground -referenced. The SCC-LP XX input circuitry includ es high-impedance bias resistors t ypically required for floating sources.
SCC-LP Series Lowpass Filter Module s User Guide 6 ni.com Using the SCC-LP XX when Scaling V oltage Measurements If you configur ed the SCC-LP XX u sing Measurement & Automation Explorer (MAX) and you are u sing NI -DAQ , the voltage reading you get from the E Series DAQ device accounts fo r the voltage scaling effect of the SCC-LP XX .
© National Instruments Cor poration 7 SCC-LP Series Lowpass Filter Modul es User Guide Input bias current .............. .............. ....... ± 2 nA typ ± 5 nA max 1 Nonlinearity ... ................. ................ ....... 0.004% of full scale Filter Characteristics Filter type .
SCC-LP Series Lowpass Filter Module s User Guide 8 ni.com Stability Gain temperature coefficient .............. ....10 ppm/°C typ 20 ppm/°C m ax Offset-voltage temperature coefficient . ... .............. .........3.4 µ V/°C typ (RTI) 27 µ V/°C max Power Requirement Analog power SCC-LP01, SCC-LP02 .
© National Instruments Cor poration 9 SCC-LP Series Lowpass Filter Modul es User Guide Humidity ............. ................. .............. .... 10 to 90% RH, noncondensing Maximum altitude ................... ............... 2,000 m Pollution Degree (indoor use only) .
SCC-LP Series Lowpass Filter Module s User Guide 10 ni.com Theor y of Operation SCC-LP XX Performance The SCC-LP XX uses a Butterworth filter, which is characterized by maximal flatness in the passband with very sharp monotonic rol loff.
© National Instruments Corpor ation 11 SCC-LP Series Lowpass Filter Modul es User Guide Figure 3. T ypical SCC-LP02 Response Curve Figure 4. T ypical SCC-LP03 Response Curve F requency (Hz) Amplitude (dB) – 25.0 1 2 3 4 5 10 20 25 50 100 – 20.0 – 15.
SCC-LP Series Lowpass Filter Module s User Guide 12 ni.com Figure 5. T ypical SCC-LP04 Response Curve 1 2 3 4 5 10 20 50 1000 2000 –25.0 –20.0 –15.
© National Instruments Corpor ation 13 SCC-LP Series Lowpass Filter Modul es User Guide Figure 6 shows the theoretical transf er characteristics of the SCC-LP XX . Figure 6. Theoretical T r ansfer Characte ristics a. Frequency Response 0 0.1 0.15 0.5 Normalized F requency (f/fc) Amplitude (dB) 1 1.
SCC-LP Series Lowpass Filter Module s User Guide 14 ni.com The horizontal axes of the first tw o plots are normali zed to the SCC-LP XX cutof f frequency . W hen the input freq uency (f ) equals the cuto ff fr equenc y (fc), the normalized frequency has a v alue of 1.
© National Instruments Corpor ation 15 SCC-LP Series Lowpass Filter Modul es User Guide Using the SCC-LP XX as an Antialiasing Filter Aliasing, a phenomenon of voltage-sampling systems, causes a high-fre quency signal to take on th e identity of a low-frequency signal.
SCC-LP Series Lowpass Filter Module s User Guide 16 ni.com Calibrating Gain Errors The SCC-LP XX is calibrated at the facto ry before shipment. If you want to calibrate the SCC-LP XX in your system, you need a vol tage source capable of providing a D C voltage up to ± 10 V that is several times more accu rate than the SCC itself.
© National Instruments Corpor ation 17 SCC-LP Series Lowpass Filter Modul es User Guide SCC-LP XX Module Pin Assignments Figure 8 shows the I/O connector pin s on the bottom of the modul e.
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Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il National Instruments SCC-LP02 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del National Instruments SCC-LP02 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso National Instruments SCC-LP02 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul National Instruments SCC-LP02 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il National Instruments SCC-LP02, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del National Instruments SCC-LP02.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il National Instruments SCC-LP02. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo National Instruments SCC-LP02 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.