The most known and simple level switch consists of a float which is mounted on a moveable arm and magnetically coupled to a micro switch (outside the process). Also versions exist with a spherical float, which contains a small magnet and move upwards a tube. In the tube one or more reed relays are placed. The reed relays will switch as the (magnetic) float passes by. The image below shows a simple float type mechanism.
Advantages of Float level switch
1. Relatively simple.
2. It is suitable for various products
3. Low cost.
Disadvantages of Float level switch
1. Requires a certain mounting
2. No reproduction switch point
3. There is a malfunction in case of build-up.
4. It is not fail-safe.
