Data Acquisition Starter Kit FAQs

Click on the question to see the answer:

1. What software is provided with a starter kit?
2. Can I port data to Microsoft Excel using any of the software that is provided?
3. What kinds of signals can I measure with a starter kit?
4. Can I measure process currents (4-20mA, 0-10mA, etc.) with a starter kit?
5. What is the input impedance of a starter kit?
6. What is the maximum sample rate for a starter kit?
7. What is the range of sample rates supported by starter kits (models DI-154RS, -194RS, and -195B)?
8. What signal frequencies can I measure with a starter kit?
9. Shouldn't the maximum frequency I can measure be one-half the maximum sample rate, or 120 Hz?

1. What software is provided with a starter kit?
   All starter kits are provided with WinDaq/Lite data recording, playback, and analysis software, and an ActiveX control library that allows them to be used with any Windows programming language, like Visual BASIC and LabVIEW.
2. Can I port data to Microsoft Excel using any of the software that is provided?
   The playback component of WinDaq/Lite software supports the ability to export any range of acquired data in a variety of different formats. The most popular of these is a CSV, or comma separated value format, which may be opened directly by Excel. Alternately, consider WinDaq/XL software to port data to Excel in real time during acquisition.
3. What kinds of signals can I measure with a starter kit?
   Models DI-194RS and DI-154RS may be connected to preamplified signals in the range of ±1V to ±10V full scale. They are not suitable for measuring millivolt-level signals, or any voltage over 10V. Examples of low level signals that are not suitable are directly connected thermocouples, thermistors, RTDs, strain gages or strain gage-based transducers. For more flexible input levels, check out one of the following: DI-149, DI-158 Series, or DI-710 Series.
4. Can I measure process currents (4-20mA, 0-10mA, etc.) with a starter kit?
   Not typically. These measurements are made using shunt resistors that typically produce 1 to 5V for a 4-20mA current. However, the 1 to 5V signal may be off-ground by the magnitude of the power supply voltage (usually 28 VDC) that powers the loop. This magnitude is enough to damage a starter kit. In such situations, consider our model DI-158 with isolated DI-5B32 or DI-5B42 process current amplifiers.
5. What is the input impedance of a starter kit?
   Models DI-194RS and DI-154RS provide input impedances greater than 200 KΩ.
6. What is the maximum sample rate for a starter kit?
   The DI-154RS and DI-194RS data acquisition starter kits sample at a maximum rate of 240 Hz throughput, meaning you can sample one channel at 240 Hz, two channels at 120 Hz per channel, three channels at 80 Hz per channel, and 4 channels at 60 Hz per channel. The DI-158 Series and the DI-149 can record at much higher rates (up to 14,400 Hz) when used with the high speed version of WinDaq acquisition software.
7. What is the range of sample rates supported by starter kits (models DI-154RS, -194RS, and -195B)?
   Sample rates are calculated by WinDaq/Lite software using the following formula: sample rate = 240 ÷ n samples per second, where n=1 to 32767. Sample rates may range from approximately 26 samples per hour to 240 samples per second.
8. What signal frequencies can I measure with a starter kit?
   If we assume a sine wave input, the maximum signal frequency that may be adequately resolved is around 5 Hz for a single channel. This yields 48 points per sine wave cycle (240 samples per second ÷ 5 Hz). Of course, DC signals, or signals that change very slowly with respect to time, may be sampled at much lower rates.
9. Shouldn't the maximum frequency I can measure be one-half the maximum sample rate, or 120 Hz?
   The Nyquist theory does not apply to starter kits, or any other situation where an anti-alias filter is not present. Of course, if you provide your own anti-alias filter external to the starter kit, the theory would apply just like any other data acquisition situation.