Johnson Controls NXA-FCU-01 Installation Manual page 4

SYMBOLS
Installation Guide
This is the symbol for Electro-Static Discharge. Electro-Static
Discharge (ESD) can damage certain electronic devices. ESD is a
transfer of electrostatic charge between bodies at different
electrostatic potentials caused by direct contact or induced by a electrostatic
field. The threshold for feeling an electro-static discharge is approximately 900
to 1000 volts. The average spark produced by a static discharge from a human
body varies from about 10,000 to 25,000 volts.
ESD can cause damage to integrated circuits (IC). Due to the small size of
these complex devices, the ESD sensitivity has increased so much that some
of these devices can be destroyed or damaged by as little as 20 volts. ESD
damage is easy to induce, hard to detect, and is expensive to repair. Workers
could be subjecting an electronic device to lethal voltages without being aware.
The following is a list of precautions when handling static sensitive devices.
• A conductive ground strap should be worn to assure that you are at ground
potential. If a ground strap cannot be used, you should ground yourself
before touching the device and remain in contact with a grounded metallic
object during the entire time while working with the device.
• Containers, tools, test equipment, and fixtures that come into contact with
the device should be properly grounded. Grounding of electrical equip-
ment should be done by a grounded plug, not through the conductive
surface of the grounded workstation.
• Workers clothing should never make contact with the device and workers
should avoid activities that cause friction in the area of the workstation
(wiping feet, rubbing of hands, etc.).
• Workers should avoid touching leads or contacts.
This is the symbol for caution and represents possible equipment
damage. When this symbol appears, follow the succeeding text to
prevent possible equipment damage.
This is the symbol for danger and represents possible bodily injury or
threat to life and limb. When this symbol appears, follow the
succeeding text closely for safe operation.
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FCU Controller