I-Data POLARIS Panel PC 19.1" - Manual (Page 19)

User manual
POLARIS Panel PC 19.1'' and Panel PC 15''
Version 2.00
Page 19 of 46
E_BMS790_POLARIS_PanelPC_19+15_Rev1.doc • User manual for POLARIS Panel PC 19.1" and 15" • Revision 1 / Status: January, 3 rd , 2006 • Technical data subject to change
3.3.4
Connection of shielding
■
A low impedance connection to the circuit protective conductor is important to ensure a low
current fault path.
■
When sub-D connectors are used, the shielding should always be connected to the metal
casing of the sub-D plug.
■
The plug casing of some controllers is not always well connected to earth. In such cases it
may prove advantageous to insulate the shielding from the sub-D plug of the controller and
connect it directly with the protective earth conductor by means of a cable that should be
kept as short as possible (0.75 mm² …1.5 mm²).
3.3.5
Examples of how shielding can be connected
Connection of shielding at both ends of the cables linking the controller and POLARIS Panel PC:
Generally, connection of the shielding at both ends results in optimum damping of all interference frequencies. This method
is to be recommended when there is good equipotential bonding between the individual units. In such cases it is possible to
make use of the controller’s voltage supply cable even if this is not electrically isolated.
Controller
Earth
POLARIS
Panel PC
Shielding