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Grounding and Bonding Electrical Systems | NEC Code - National Electrical Code Article 250 is all about grounding and bonding as represented in this photo where electrical systems are grounded and bonded to the buildings steel structure.
There are many different rules in the NEC (National Electrical Code) pertaining to grounding and bonding because grounding and bonding are important for safety reasons. Electricity will take the path of least resistance so if there is a short in the system the grounding system will be the path for the electricity instead of the motor or load that experiences the short.
Grounding and Bonding Electrical Systems And Safety
The NEC defines specific sizes for grounding wires based on the size of the wire serving the building plus each different load has specific grounding and bonding requirements. For example, a rooftop air handler may have several loads including a supply fan and a return fan. Each fan motor will have specific needs for grounding wire size in relation to the size of the wire supplying electricity to the motor.
In a residential setting, it is important to follow the code and ensure your equipment and everything else including receptacles have a good ground for the protection and safety of yourself and other occupants. Additionally, for swimming pools and spas, it is ultra important to ensure the grounding system is correct for the pool or spa since there are water and electricity and these two are definitely dangerous when mixed. So make sure you get a qualified electrician and have the job inspected by a qualified inspector before using the pool or spa or allowing others to use the pool or spa.
Grounding and Bonding Electrical Systems - Additional Resources
As an HVAC Technician, I used to carry around a little book called the Ugly Book. It is feature rich with lots of basic electrical information references to help a technician make decisions in the field. If you are an HVAC Service Technician you really need this book. It will give you quick access to formulas and wire sizing and other pertinent electrical information to help you solve problems.
Grounding and Bonding Electrical Systems and the NEC
