Powder Pilot
™ HD
P/N 7192721_02
Page | 8
PE (Protective Earth) Grounding
PE grounding is required on all conductive metal electrical enclosures in a
system. PE grounding is provided by a ground conductor wire bonded to a true
earth ground. PE grounding protects operators from electrical shock by providing
a path to ground for electrical current if a conductor contacts an electrical
enclosure or other conductive component. The ground conductor wire carries
the electrical current directly to ground and short circuits the input voltage until a
fuse or circuit breaker interrupts the circuit.
The green/yellow ground wires bundled with the AC input power cable are used
only for PE grounding and their sole purpose is to protect personnel from a
shock. These ground wires do not protect against electrostatic discharge.
Electrostatic Grounding
Electrostatic grounding protects electronic equipment from damage caused by
electrostatic discharges (ESD). Some electronic components are so sensitive to
ESD that a person can deliver a damaging static discharge without feeling even
a mild shock.
Proper electrostatic grounding is mandatory in an electrostatic powder coating
system. Powder spray guns generate electrostatic voltages up to 100,000 volts.
It does not take long for ungrounded system components to build up an
electrical charge strong enough to damage sensitive electronic components
when discharged.
Electrostatic discharges occur at very high frequencies, around 100 megahertz.
An ordinary ground conductor does not conduct such high frequencies well
enough to prevent damage to electronic components. Special flat braided cables
are provided with your Nordson powder coating equipment to protect against
ESD.
