Esd Protective Measures; About The Physics Of Electrostatic Charges - Sirona SIROEndo Instrucciones De Uso

1 Warning and safety information
1 nanosecond
= 1/1,000,000,000 second
=
1 billionth of a second
6
1.2

ESD protective measures

ESD stands for ElectroStatic Discharge.
CAUTION
Connector pins or sockets bearing ESD warning labels must not be touched or
interconnected without ESD protective measures.
ESD protective measures include:
• Procedures for preventing electrostatic charge build-up (e.g. air condition-
ing, air moistening, conductive floor coverings and non-synthetic clothing)
• Discharging the electrostatic charges of your own body on the frame of
the , the protective ground wire or large metallic objects
UNIT
• Connecting yourself to ground using a wrist band
We therefore recommend that all persons working with this system be
instructed on the significance of this warning label. Furthermore, they also
should receive training in the physics of electrostatic discharges which can
occur in the practice and the destruction of electronic components which may
result if such components are touched by electrostatically charged
The content of this training is explained in Chapter 1.3.
1.3 About the physics of electrostatic
charges
ESD stands for ElectroStatic Discharge. Electrostatic discharge must be pre-
ceded by electrostatic charging.
Static electric charges generally build up whenever two bodies are rubbed
against each other, e.g. when walking (shoe soles against the floor) or driving
a vehicle (tires against the street pavement). The amount of charge depends
on several factors:
Thus the charge is higher in an environment with low air humidity than in one
with high air humidity; it is also higher with synthetic materials than with natu-
ral materials (clothing, floor coverings).
The following rule of thumb can be applied to assess the transient voltages
resulting from an electrostatic discharge.
An electrostatic discharge is:
• perceptible at 3,000 V or higher
• audible at 5,000 V or higher (cracking, crackling)
• visible at 10,000 V or higher (arc-over)
The transient currents resulting from these discharges have a magnitude of
10 amperes. They are not hazardous for humans because they last for only
several nanoseconds.
Voltage differentials exceeding 30,000 volts per centimeter may lead to a
charge transfer (electrostatic discharge, lightning, arc-over).
Operating Instructions SIROEndo
60 78 104 D 3488
D 3488.201.01.07.02 11.2009
.
USERS