Intelligent Technologies (IT.) D77A I/O Module Products
Analog Input Modules
Figure 20 illustrates the basic signal processing operation. Analog signals from four separate channels are received by a multiplexer (MUX). The MUX sequentially transfers this data to an analog-to-digital converter (ADC). The ADC measures the analog signal and converts it to a digital value. This digital value is presented to the controller’s central processes unit (CPU). This data is then presented to the QCPort for external processing.
V0 |
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I0 |
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V1 | M |
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I1 | U |
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V2 | X |
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I2 |
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V3 |
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I3 |
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C0 |
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C1 | V1 | +V2 |
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C2 |
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C3 |
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Figure 20: Analog Input Module Operation
Analog input signal delays are associated with multiplexer switching, channel updating and channel reconfiguration. These delays are all influenced by analog input filter frequency selection.
Table 24: Analog Input Signal Delays
Filter Setting | Total Update Time |
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50 Hz | 336 ms |
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60Hz | 283.2 ms |
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250 Hz | 80 ms |
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500 Hz | 44 ms |
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MN05002001E | For more information visit: www.EatonElectrical.com | 25 |
