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STATIC PREVENTION
The Sterling Scale XC780 has been tested for ElectroStatic Discharge(ESD)
susceptibility according to the new international 801.2 air discharge ESD
standard(150 ohm, 150 pF). The XC780 was tested to withstand 25,000 Volts ESD
non-destructive and 15,000 volts ESD non-disruptive.
Line transient tests have also been performed on the XC780 using the standard
IEEE 587 line transient standard category A(8 usec x 20 usec pulse). The XC780
was tested to withstand 6000 Volts non-destructive and 5000 Volts non-
disruptive.
Because the XC780 piece counter is often used in harsh industrial environments,
extensive static, EMI, and RFI protection has been designed into the
instrument. For these protective measures to work correctly, some special
considerations must be made in high static, EMI, and RFI environments.
NOTE:
Most applications of the XC780 WILL NOT need these extra
considerations. Only environments that generate greater than 15,000 volts of
static interference need additional protection.
Electrostatic Discharge(ESD):
Static electricity buildup is present on any surface which develops an
electrical charge which cannot be dissipated as fast as it is developed.
ElectroStatic Discharge(ESD) occurs when this developed charge finds a quick
and easy path to discharge. For example, when you walk across a rug in leather
shoes(the triboelectric effect) on a dry day, the motion of your shoes against
the rug develops an electrical charge faster than it can be
dissipated(dissipated either through the air or your feet). Now when you reach
for a door knob, the built-up charge discovers a discharge path to that door
knob. The snap that you feel is the ElectroStatic Discharge.
There are three ways to stop the Static Voltages from damaging electronic
equipment:
1. Stop the static buildup- The first and most effective method of
stopping static damage is to not allow static to be generated in the first
place. Humidifying the air, using conductive forklift tires, and special
storage and shipping containers will all help minimize static build up.
2. Dissipate the static charge- The charge can be dissipated, or "bled
off". This way it never reaches dangerous levels and static damage can be
avoided. Personnel can wear static straps or special conductive floor mats and
table tops can be installed in the static area. Fork lift trucks can drag
static straps and filling machinery can be grounded. A conductive path to
ground on anything or anyone that generates static, can help eliminate static
problems before they build up.
3. Provide an alternate discharge path- This is accomplished in the
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