When telling someone to stay grounded, we mean to tell them to remain calm and stable. Would the same concept apply to grounding high voltage systems? So how exactly does grounding come into play here? Let's find that out in this blog!
What is a Ground?
A ground is a reference point of zero voltage, relative to which all other voltages are measured. This serves as a way to determine faults in a system. It also enables a path for the excessive charge to pass through a system, preventing damages safely. Now you might be wondering, what can I use as my ground? The answer to this is straightforward. You can use the literal ground that you stand on as your reference point!
The Earth serves as the best ground for several reasons:
- It is neutrally charged.
- It has zero potential.
- Can store an infinite amount of charge.
- It is available for free.
To ground a system, one terminal of the system is connected to the Earth through a low impedance. In case of a short circuit, touching of wires with metal surfaces, or lightning, the surplus voltage is directed towards the Earth.
Types of grounding
There are different types of grounding, depending on the client's needs and how they want their systems to operate.
Ungrounded Systems
Even though not commonly used, ungrounded systems are still critical to be discussed. In the case of ungrounded systems, there exists direct path between the lines and the ground. Instead, capacitors are used to store up the excess charge/energy. As a result, there is no ground fault charge produced, and the system can continue operating without any interruptions. However, with no grounding wire to take up the excess charge, the burden on the live wires increases. They can end up losing their outermost insulation, short-circuiting, and causing a fire.
Resistance grounding
In this arrangement, a resistor is attached to the neutral wire to reduce the current flow. If the neutral wire is carrying a controlled amount of charge back to the source, chances of a hazard or fire are minimized.
In a low resistance grounding, the protective devices in the system are alerted about the fault through ground fault charge. Accordingly, the devices can shut down the supply to prevent damages. On the other hand, the ground-fault current is minimized in a high resistance grounding. Interestingly, the system does not stop operating while controlling damages.
Solid grounding
This type of grounding establishes a direct path between the power system and the ground, often through the neutral point. Vast amounts of ground fault charge are produced, leading to a low risk of hazards and damages. However, the system stops operating until the fault is restored!
Conclusion
As you have seen, a power system has many valuable components that need protection for a smooth operation and reduced damage costs. So, if you want a secure setup, feel free to visit Swartz Engineering to get the best grounding products.