Omega OM-USB-1208FS manual ADC transfer function with offset error

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OM-USB-1208FS User's Guide

Functional Details

Figure 10. ADC transfer function with offset error

Gain error is a change in the slope of the transfer function from the ideal, and is typically expressed as a percentage of full-scale. Figure 11 shows the OM-USB-1208FS transfer function with gain error. Gain error is easily converted to voltage by multiplying the full-scale (FS) input by the error.

The accuracy plots in Figure 11 are drawn for clarity and are not drawn to scale.

Figure 11. ADC Transfer function with gain error

For example, the OM-USB-1208FS exhibits a typical calibrated gain error of ±0.2% on all ranges. For the ±10 V range, this would yield 10 V × ±0.002 = ±20 mV. This means that at full scale, neglecting the effect of offset for the moment, the measurement would be within 20 mV of the actual value. Note that gain error is expressed as a ratio. Values near ±FS are more affected from an absolute voltage standpoint than are values near mid- scale, which see little or no voltage error.

Combining these two error sources in Figure 12, we have a plot of the error band of the OM-USB-1208FS for the ±10 V range. This is a graphical version of the typical accuracy specification of the product.

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Contents Page Page Table of Contents OM-USB-1208FS Users Guide Conventions in this user’s guide Where to find more informationAbout this Users Guide What you will learn from this user’s guideChapter Introducing the OM-USB-1208FSSoftware features OM-USB-1208FS block diagramConnecting a OM-USB-1208FS to your computer is easy Hardware Installing the OM-USB-1208FSWhat comes with your OM-USB-1208FS shipment? Unpacking the OM-USB-1208FSIf the LED turns off Installing the softwareInstalling the hardware Be sure you are using the latest system softwareTheory of operation analog input acquisition modes Software paced modeContinuous scan mode Functional DetailsScrew terminal wiring USB connectorScrew terminal pins Single-ended configuration Main connector and pin outAnalog input terminals CH0 in CH7 Differential configuration Single-ended measurements using differential channelsChhi Chlo Analog output terminals D/A OUT 0 and D/A OUT Power terminalsFor more information on analog signal connections For more information on digital signal connectionsSync terminal Calibration terminalGround terminals External trigger terminalIdeal ADC transfer function AccuracyADC transfer function with offset error Error band plot OM-USB-1208FS channel gain queue featureSynchronizing multiple units Configuring for synchronous data acquisitionAnalog input SpecificationsRange Accuracy LSB Digital input/output Analog outputExternal clock input/output External triggerCounter Non-volatile memory PowerMicrocontroller Environmental Main connector and pin outChannel differential mode GeneralChannel single-ended mode

OM-USB-1208FS specifications

The Omega OM-USB-1208FS is a high-performance data acquisition device designed for engineers and technicians who require accurate data logging and analysis in their experiments and applications. This versatile device is equipped with a range of features that make it an ideal choice for various measurement tasks across different industries.

One of the standout features of the OM-USB-1208FS is its ability to support a wide variety of input signals. The device is equipped with 16 analog input channels, which can be used for both voltage and thermocouple inputs, making it suitable for temperature monitoring and other signal measurements. The analog inputs provide a resolution of 16 bits, ensuring precise and reliable readings. Furthermore, it supports sampling rates of up to 100 kS/s, allowing for rapid data acquisition and real-time monitoring.

In addition to its analog capabilities, the OM-USB-1208FS has digital I/O lines that facilitate control and automation tasks. With 8 digital input/output channels, users can easily manage various external devices, sensors, or actuators, enhancing the overall functionality of the data acquisition system. This makes the device suitable for automation projects, as users can trigger actions based on acquired data.

Another distinguishing feature is the built-in USB interface, which offers a straightforward connection to computers without the need for additional power supplies or complex setups. The device is fully compatible with various operating systems, including Windows, making it easy to integrate into existing systems. The included software allows for easy data logging, visualization, and analysis, simplifying the process for users.

The OM-USB-1208FS is designed with durability and reliability in mind. Its compact and rugged construction ensures that it can withstand the rigors of fieldwork and laboratory use. Moreover, the device's comprehensive range of input types and robust performance specifications make it an asset for researchers across diverse fields, including environmental monitoring, manufacturing, and academic research.

In summary, the Omega OM-USB-1208FS is a powerful data acquisition solution that combines a multitude of features and technologies. With its high-resolution analog inputs, digital I/O capabilities, user-friendly USB interface, and reliable construction, it caters to the diverse needs of professionals seeking to capture and analyze data accurately and efficiently. Whether for academic research, industrial applications, or environmental monitoring, the OM-USB-1208FS stands out as a top choice in the data acquisition landscape.
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