Earthing straps, or grounding straps, connect an electrical system to the conductive surface of the earth for safety. They provide an outlet for excess current if there is a fault in the system, allowing the current to flow into the earth.
Earthing straps are also commonly used as antistatic devices. When someone is working on sensitive electrical equipment, they might need to prevent build up of static, which could cause sparks to fly and damage equipment.
How do earthing straps provide security?
In the event of a fault, earthing straps provide protection by drawing current away from the equipment or worker and into the ground. If the current gets too high, the circuit should also be protected by a device such as a thermal magnetic circuit breaker.
Types of earthing straps
There are broadly two types of earthing straps: those that are for use on humans, and those that are for use directly on equipment.
Antistatic earthing straps fit around your wrist, and connect via a clamp to a ground conductor. Equipment earthing straps similarly encircle equipment, and are connected to a ground conductor via an earthing wire.