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QD1 Incremental Shaft Encoder Interface


The QD1, a general-purpose quadrature decoder, is required for some shaft encoders you may use in water-level or slope-stability applications. Please note that our CS410 Shaft Encoder does not require the QD1.

Note: A new quadrature instruction is available in the CR1000, CR800, CR850, and CR1000X dataloggers. For questions, contact Campbell Scientific. 



Note: The following shows notable compatibility information. It is not a comprehensive list of all compatible or incompatible products.

Data Loggers

Product Compatible Note
21X (retired)
CR10 (retired)
CR1000 (retired)
CR10X (retired)
CR200X (retired)
CR206X (retired)
CR211X (retired)
CR216X (retired)
CR23X (retired)
CR295X (retired)
CR500 (retired)
CR5000 (retired)
CR510 (retired)
CR9000 (retired)
CR9000X (retired)

Additional Compatibility Information

Data Logger Considerations

Two data logger pulse count channels are required. A connection to a 5 V output and ground is also required.


Connected sensors are measured by the PulseCount Instruction in CRBasic and by Instruction 3 (Pulse Count) in Edlog. The "up" versus "down" pulses are tallied in the data logger.

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