Desert Star Acoustic Release Control System, Manual

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Use a weight measuring scale designed to measure a object's weight by suspending it under the
scale. A typical mechanical fish-scale is acceptable for this evaluation. Suspend your payload
attached to the scale and submerge it under the water so that the payload is completely under the
surface of water.
STEP 3:
Take a reading of the scale and write it down. This is the weight of your payload in water.
STEP 4:
Locate the buoyancy rating of the flotation device you are planning to use. Typically it is printed on
the flotation device or specified in its technical description. This rating may be listed in Pounds or
Kilograms. For example, the buoyancy rating of a “Trawl Works” float Model #411 is rated at 18.5
lbs.
Use this formula to calculate the total weight to be held by ARC unit:
(Buoyancy rating of flotation device) - (Payload weight in water) = Total working load on ARC
release mechanism.
When calculating, make sure to keep measurement units consistent, meaning if the buoyancy of a flotation device is rated in
pounds, the weight of the payload must be measured also in pounds. If a buoyancy of a flotation device is rated in kilograms,
the weight of the payload also must be measured in kilograms.
Ideally the result should be around 10lbs to 20 lbs, however 40lbs (18 Kilograms) can be safely
tolerated. If the result exceeds this criteria, reduce the flotation device’s buoyancy.
When considering the physical shape of the payload/flotation device, please take into account strong underwater currents that
could cause excessive drag. If the physical shape is suboptimal, a strong surge in underwater current may cause an
erroneous separation of the ARC unit and payload from the anchor.
When choosing an anchor, ensure that anchor weight must always exceed buoyancy of the
equipment column (ARC unit, payload, flotation device) you are planning to deploy by a sufficient
margin in order to keep the anchor in place. Use an anchor weight at least twice the total buoyancy
of deployed column.
​ If you plan to use a significantly heavy anchor, take special care during
the deployment.
​
When the assembled column is deployed overboard, a jerking motion of the heavy
anchor thrown overboard may cause an unintended separation from the ARC unit.