National Instruments PXI-8231, Getting Started, Page: 4 / 11

© National Instruments Corporation 3 Getting Started with the NI PXI/PCIe-8231
in electrical distribution systems. The following is a description of Measurement (Installation
1
)
Categories:
• Measurement Category I is for measurements performed on circuits not directly connected to the
electrical distribution system referred to as MAINS
2
voltage. This category is for measurements of
voltages from specially protected secondary circuits. Such voltage measurements include signal
levels, special equipment, limited-energy parts of equipment, circuits powered by regulated
low-voltage sources, and electronics.
• Measurement Category II is for measurements performed on circuits directly connected to the
electrical distribution system. This category refers to local-level electrical distribution, such as that
provided by a standard wall outlet (e.g., 115 V for U.S. or 230 V for Europe). Examples of
Measurement Category II are measurements performed on household appliances, portable tools,
and similar products.
• Measurement Category III is for measurements performed in the building installation at the
distribution level. This category refers to measurements on hard-wired equipment such as
equipment in fixed installations, distribution boards, and circuit breakers. Other examples are
wiring, including cables, bus-bars, junction boxes, switches, socket-outlets in the fixed installation,
and stationary motors with permanent connections to fixed installations.
• Measurement Category IV is for measurements performed at the primary electrical supply
installation (<1,000 V). Examples include electricity meters and measurements on primary
overcurrent protection devices and on ripple control units.
Unpacking
The NI 8231 ships in an antistatic package to prevent electrostatic discharge from damaging device
components. To avoid such damage in handling the device, take the following precautions:
1. Ground yourself using a grounding strap or by touching a grounded object, such as the computer
chassis.
2. Touch the antistatic package to a metal part of the computer chassis before removing the device
from the package.
Caution
Never touch the exposed pins of connectors.
3. Remove the device from the package and inspect it for loose components or any other signs of
damage. Notify National Instruments if the device appears damaged in any way. Do
not install a
damaged device in the computer.
Store the NI 8231 in the antistatic package when not in use.
Installation
The following instructions are for general installation. Refer to the documentation provided by your
computer manufacturer for specific instructions and warnings. Refer to the
Specifications section for a
list of the typical power requirements for the NI 8231.
1
Measurement Category is also referred to as Installation Category.
2
MAINS is defined as the (hazardous live) electrical supply system to which equipment is designed to be connected for the
purpose of powering the equipment. Suitably rated measuring circuits may be connected to the MAINS for measuring
purposes.