Isolators can transfer electrical signals without a metallic connection. More importantly, they are safety devices that provide electrical protection between two circuits. Isolators typically protect the logic or low voltage side of the circuit from another that is connected to the field, where it can introduce high electrical transients from noisy equipment or accidental shorts from high voltage sources. Isolators can also protect human interface from electric shock by high voltage equipment. In addition to protection, isolators are used as, level shifters – to harmonize between systems with different voltages, decoupling common mode voltages from one circuit to another – so that any sudden ground potential changes would not affect the integrity of the signal, and breaking ground loops prevent any current from signal distortion due to ground differences. Isolators ‘pass’ electrical signals over an insulation material, which is capable of withstanding high voltages.