Carlon Structured Cable Management Systems Handbook - Low Res - Manual (Page 35)

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generate electric and magnetic fields. These fields in
turn can move electrons in nearby conductors, causing
an electrical disturbance. EMI occurs when electrical
energy causes an undesired response in a piece of
electrical equipment.
• The source can be natural. It can be caused by
lightning or electrostatic discharge.
• The source can human-made. It can be caused by
another piece of electrical or electronic equipment.
EMI is any unwanted electrical energy that interferes
with the intended operation of a piece of electronic
equipment or reception of a signal. EMI is also called
electronic noise.
The degree of EMI can vary:
NUISANCE: The microwave oven makes the TV
noisy while you are making popcorn.
MODERATE: Static or sounds from another line
makes it hard to talk on the phone.
SERIOUS: Voltage spikes on a bank’s internal net-
work cause the bank’s computers to
lose a day’s transaction records.
WHAT CAUSES EMI?
EMI can arrive through a direct connection. For exam-
ple, currents in earth ground wires can cause EMI,
where two pieces of equipment have the same
ground. Also, a failed component in one piece of
equipment anywhere on a shared circuit can cause
EMI.
EMI can enter a circuit by radio wave or magnetic field
coupling from a nearby electrical device. For example,
a power cable or an electric motor close to a data
cable can interfere with the signal in a data cable.
WHAT TYPES OF CIRCUITS ARE AFFECTED BY
EMI?
Resi-Gard General Purpose Raceway is approved and
acceptable for a wide variety of signals.
These include:
Gross Automation (877) 268-3700 · www.carlonsales.com · [email protected]