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Current Meter Maintenance Information and Resources

The AquaCalc is used with mechanical Current Meters like the USGS style Price AA and Pygmy current meters. These current meters most often use a contact switch to indicate a revolution of the cups. In modern current meters this is most likely a magnetic reed switch, but in older current meters this can be a small wire, often called a “cat whisker” that touches a rotating cam in the current meter switch head. AquaCalc also makes a Pygmy Digital Magnetic Head for the Pygmy current meter. This magnetic sensor uses a Hall Effect sensor, and is designed to work with AquaCalc.

Pygmy Meter with PMH 2019c



Some of these resources are old, but still good.

I have attached a paper on current meter maintenance, and a manual for a Price AA current meter made by Rickly Hydrological.

The USGS has an educational site that discusses discharge measurement in broad terms here:


The USGS has more detailed training materials and a report on Discharge Measurements here:


(The whole report can be downloaded here:

https://pubs.usgs.gov/twri/twri3a8/pdf/TWRI_3-A8.pdf )

And finally the old “bible” of the USGS Water Supply Division: “Water Supply Papers 2175 - Measurement and Computation of Streamflow”. This has a lot of information and theory:




Current Meter Resources

AquaCalc LLC. telephone +1.916.372.0534 e-mail: sales@aquacalc.com

Need Accessories or Cables?

We have replacement parts and cables for the AquaCalc line of stream flow computers including the Digital Pygmy Magnetic Head retro fit your old Pygmy Current Meter with a new digital magnetic sensor.

Find Accessories and Cables here.

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