Each device, at each plant, must be set to allow water through it at the weight pre-set for each basket or potted plant by adjusting the wing nut on the device. The device will react to the weight of the plant. It must be set to the desired weight of the plant, and after that it will constantly strive to maintain that weight.
Start by watering the plant to the fully watered state (from hose or a watering can), and hang the plant onto the device.
Turn the wingnut on the device to relax the control spring. This will cause any flow that might already be flowing to stop. If the water to the Plant Booster system is not already on, turn it on.
Turn the wingnut clockwise to tighten the control spring until water starts flowing through the device and into the plant. Because you have already fully watered the plant in the first step above, now turn the wingnut back a little so that the water just stops flowing.
Test that the water will flow if you just lightly lift the plant. The device should now be set correctly. Any reduction in the weight of the plant will now cause the device to allow water to flow to replace that weight loss.
There should be no excess water dripping from the plant. If that does happen the device wing nut must be backed off a little so it stops adding water to the plant. It may take a few days to find the optimum water content or weight at which no excess water will drain from the plant.
The real beauty of this system is that each plant therefor gets individual attention. Two identical plants, one in the sun, and the other in the shade will have different water requirements. This makes it unique from a regular timer operated drip irrigation system where all plants get water from a set period each day, whether they need it or not.