BCT-ETX-C3-XXX
S
INGLE
B
OARD
C
OMPUTER
I
NTRODUCTION
The board must be installed in a computer system chassis that provides screening suitable for an
industrial environment.
Any recommendations made by the computer system manufacturer/supplier must be complied with
regarding earthing and the installation of boards.
Any metal back plate must be securely screwed to the chassis of the computer to ensure good metal-to-
metal (i.e. earth) contact.
Connector bodies must be securely connected to the enclosure.
The external cabling to boards causes most EMC problems. It is imperative that any external cabling to
the board is totally screened, and that the screen of the cable connects to the metal end bracket of the
board or the enclosure and hence to earth. It is recommended that round, screened cables with a braided
wire screen are used in preference to those with a foil screen and drain wire. Use metal connector shells
that connect around the full circumference of the cable screen: they are far superior to those that earth
the screen by a simple “pig-tail”.
The keyboard and mouse will play an important part in the compatibility of the processor card since they
are ports into the board. Similarly, they will affect the compatibility of the complete system. Fully
compatible peripherals must be used otherwise the complete system could be degraded. They may
radiate or behave as if keys/buttons are pressed when subject to interference. Under these circumstances
it may be beneficial to add a ferrite clamp on the leads as close as possible to the connector. A suitable
type is the Chomerics type H8FE-1004-AS.
USB cables should be high quality screened types.
Ensure that the screens of any external cables are bonded to a good RF earth at the remote end of the
cable.
Failure to observe these recommendations may invalidate the EMC compliance.
Warning
This is a Class A product. In a domestic environment this product may cause radio
interference in which case the user may be required to take adequate measures.