Y s i, D-3. installing the system – YSI ADV6600 User Manual

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Appendix D. Frequently Asked Questions

ADV6600

Y S I

Environmental

Page 166

D-3. Installing the System



How should I deploy my ADV6600 for long term monitoring studies of water current and
quality?

An ADV6600 can collect valid velocity data when deployed using the following methods.

• Mounted directly to a vertical pole

• Mounted vertically in a PVC pipe that is attached to a pole, bridge abutment, or similar

structure

• Deployed vertically using a rope or chain as a tether

There are, however, significant factors of which you need to be aware that will affect the quality and
accuracy of the ADV data.

• Significant rotations of the system can create with the compass (described in the following

section) that can temporarily compromise velocity measurements.

• There must be sufficient scatterers in the water so that accurate velocity measurements can be

made (described in the preceding section). A Beam Check should be performed at all sites
before a deployment, and is a must at sites where the water is very clear.

• There must be minimal magnetic interference to avoid influencing compass readings (see

compass section). If possible, all mounting fixtures should be made of stainless steel,
aluminum, or plastic. If the mounting fixture must contain magnetic (ferrous) material, it needs
to be stationary in relation to the ADV6600, i.e., the interfering material and the ADV6600
should be attached to one another. A compass calibration and verification should be performed
before each deployment at the site with the sonde in the mounting apparatus.

• The ADV sensor needs to be submerged to make accurate velocity measurements.

• Flow interference (caused by the mount, pilings, rocks, weeds, etc.) will affect velocity

measurements. For this reason, deployment location must be considered carefully to be sure that
the sampling area of the ADV is free from these disturbances for the entire deployment.

• The system can be deployed on the inside of a pipe but the Doppler sensor must be located

below the bottom of the pipe at least as far as it extends below the probe guard (see picture in
Section 5-1.2 above) for proper performance.

• It is important to select a deployment site that is representative of the flow that you are trying to

measure. Environmental stability (i.e., not subject to massive changes in conditions) is
preferable but not required.

• If data will be collected in the internal memory of the ADV6600 during an autonomous

deployment, the recorder must be enabled.

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