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CHAPTER 4:
ELECTRICAL INSTALLATION
NOTE:
The datasheet is the first document to refer to for model-specific information related to I3N models
for key installation information. Visit the IMO websites to obtain datasheets, user documentation, and
updates.
4.1 Grounding Definition
Ground:
The term
ground
is defined as a conductive connection between a circuit or piece of equipment
and the earth. Grounds are fundamentally used to protect an application from harmful interference
causing either physical damage such as by lightning or voltage transients or from circuit disruption often
caused by radio frequency interference (RFI). Grounding is also for the safety of the user.
4.2 Ground Specifications
Ideally, a ground resistance measurement from equipment to earth ground is 0
Ω
. In reality, it typically is
higher. The U.S. National Electrical Code (NEC) states the resistance to ground shall not exceed 25
Ω
. IMO
recommends less than 15
Ω
resistance from our equipment to ground. Resistance greater than 25
Ω
can
cause undesirable or harmful interference to the device.
