6-6
IMACS System Release 5.1.9
Reference Guide
Model No.
Running Head
Interface Card Descriptions
Interface Card
6.2.1.6
Equipment Grounding Requirements
When connecting cables from other AC-powered equipment (such as computer terminals) to
the Interface card,
make sure the other equipment is properly grounded
. Ground
connections are normally provided by the ground (third) prong of an AC plug. Some PCs,
especially portables and laptops, have power supplies with two-pronged plugs; they are not
properly grounded.
When a cable is run from a PC that is not properly grounded to the Interface port of the
system, a high voltage differential (up to 100 VAC) may result between the system and
the PC. This can severely damage the Interface card, PC, or both.
As a rule, all cards with data interface connectors (RS-232, RS-422, RS-530,etc.) could be
damaged if connected to poorly grounded equipment.
All persons authorized to use or
service the Integrated Access System should be familiar with good grounding practices.
