Getting Started with the NI PCIe-8253
2
ni.com
Safety Information
The following section contains important safety information that you must follow when installing and
using the hardware.
Do not operate the hardware in a manner not specified in this document and in the user documentation.
Misuse of the hardware can result in a hazard. You can compromise the safety protection if the hardware
is damaged in any way. If the hardware is damaged, return it to National Instruments for repair.
Clean the hardware with a soft, nonmetallic brush. Make sure that the hardware is completely dry and
free from contaminants before returning it to service.
Do not substitute parts or modify the hardware except as described in this document. Use the hardware
only with the chassis, modules, accessories, and cables specified in the installation instructions or
specifications. You must have all covers and filler panels installed during operation of the hardware.
Do not operate the hardware in an explosive atmosphere or where there may be flammable gases or
fumes unless the hardware is UL (U.S.) or Ex (EU) Certified and marked for hazardous locations.
The hardware must be in a suitably rated IP 54 minimum enclosure for hazardous locations. Refer to
the hardware’s user documentation for more information.
You must insulate signal connections for the maximum voltage for which the hardware is rated. Do not
exceed the maximum ratings for the hardware. Do not install wiring while the hardware is live with
electrical signals. Do not remove or add connector blocks when power is connected to the system. Avoid
contact between your body and the connector block signal when hot swapping hardware. Remove power
from signal lines before connecting them to or disconnecting them from the hardware.
Operate the hardware only at or below Pollution Degree 2. Pollution is foreign matter in a solid, liquid,
or gaseous state that can reduce dielectric strength or surface resistivity. The following is a description
of pollution degrees:
•
Pollution Degree 1 means no pollution or only dry, nonconductive pollution occurs. The pollution
has no influence. Typical level for sealed components or coated PCBs.
•
Pollution Degree 2 means that only nonconductive pollution occurs in most cases. Occasionally,
however, a temporary conductivity caused by condensation must be expected. Typical level for
most products.
•
Pollution Degree 3 means that conductive pollution occurs, or dry, nonconductive pollution occurs
that becomes conductive due to condensation.
Operate the hardware at or below the measurement category
1
marked on the hardware label.
Measurement circuits are subjected to working voltages
2
and transient stresses (overvoltage) from the
circuit to which they are connected during measurement or test. Measurement categories establish
standard impulse withstand voltage levels that commonly occur in electrical distribution systems. The
following is a description of measurement categories:
•
Measurement Category I is for measurements performed on circuits not directly connected to the
electrical distribution system referred to as MAINS
3
voltage. This category is for measurements of
voltages from specially protected secondary circuits. Such voltage measurements include signal
1
Measurement categories, also referred to as overvoltage or installation categories, are defined in electrical safety standard
IEC 61010-1 and IEC 60664-1.
2
Working voltage is the highest rms value of an AC or DC voltage that can occur across any particular insulation.
3
MAINS is defined as a hazardous live electrical supply system that powers hardware. Suitably rated measuring circuits may
be connected to the MAINS for measuring purposes.
