Siemens Simatic IPC647C, Operating Instructions Manual

Page: 222 / 246

ESD guidelines
B.1 ESD Guidelines
SIMATIC IPC647C
222
Operating Instructions, 12/2010, A5E02669337-02
Electrostatic charging
Anyone who is not connected to the electrical potential of their surroundings can be
electrostatically charged.
The figure below shows the maximum electrostatic voltage which may build up on a person
coming into contact with the materials indicated. These values correspond to IEC 801-2
specifications.
Power in kV
Synthetic material
Wool
Antistatic material, for example wood
or concrete
Relative humidity in %
(kV)
1
2
3
1
2
3
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
5 10 20 30 40 50 60 70 80 90 100
Figure B-1 Electrostatic voltages on an operator
Basic protective measures against electrostatic discharge
● Ensure good equipotential bonding:
When handling electrostatic sensitive devices, ensure that your body, the workplace and
packaging are grounded. This prevents electrostatic charge.
● Avoid direct contact:
As a general rule, only touch electrostatic sensitive devices when this is unavoidable (e.g.
during maintenance work). Handle the modules without touching any chip pins or PCB
traces. In this way, the discharged energy can not affect the sensitive devices.
Discharge your body before you start taking any measurements on a module. Do so by
touching grounded metallic parts. Always use grounded measuring instruments.