Section 8. Operation
340
differential inputs or reversing the excitation is specified, there are two separate
integrations per measurement; if both reversals are specified, there are four
separate integrations.
Analog Measurement Integration
Integration Time (ms)
Integration
Parameter Argument
Comments
0 to 16000 µs
0 to 16000
250 µs is considered fast
and normally the
minimum
16.667 ms
_60Hz
Filters 60 Hz noise
20 ms
_50Hz
Filters 50 Hz noise
Ac Power Noise Rejection
Grid or mains power (50 or 60 Hz, 230 or 120 Vac) can induce electrical noise at
integer multiples of 50 or 60 Hz. Small analog voltage signals, such as
thermocouples and pyranometers, are particularly susceptible. CR3000 voltage
measurements can be programmed to reject (filter) 50 Hz or 60 Hz related noise.
Noise is rejected by using a signal integration time that is relative to the length of
the ac noise cycle, as illustrated in the figure Ac Power Noise Rejection
Techniques
(p. 340).
FIGURE 79: Ac Power Noise Rejection Techniques
Summary of Contents for CR3000 Micrologger
Page 2: ......
Page 3: ......
Page 4: ......
Page 6: ......
Page 30: ......
Page 34: ......
Page 36: ......
Page 96: ......
Page 485: ...Section 8 Operation 485 8 11 2 Data Display FIGURE 110 Keyboard and Display Displaying Data ...
Page 487: ...Section 8 Operation 487 FIGURE 112 CR1000KD Real Time Custom ...
Page 491: ...Section 8 Operation 491 FIGURE 116 Keyboard and Display File Edit ...
Page 496: ......
Page 502: ......
Page 564: ...Section 11 Glossary 564 FIGURE 126 Relationships of Accuracy Precision and Resolution ...
Page 566: ......
Page 594: ......
Page 598: ......
Page 600: ......
Page 602: ......
Page 624: ......
Page 642: ......
Page 643: ......