Chapter 2
Installing Compact FieldPoint Hardware and Software
©
National Instruments Corporation
2-3
cFP-21xx and cFP-BP-x User Manual
•
Pollution Degree 2 means that only nonconductive pollution occurs in
most cases. Occasionally, however, a temporary conductivity caused
by condensation must be expected.
•
Pollution Degree 3 means that conductive pollution occurs, or dry,
nonconductive pollution occurs which becomes conductive due to
condensation.
Caution
You
must
insulate signal connections for the maximum voltage for which the
Compact FieldPoint product is rated. Do
not
exceed the maximum ratings for the product.
Do
not
install wiring while the product is live with electrical signals. Do
not
remove or add
connector blocks when power is connected to the Compact FieldPoint system. Avoid
contact between your body and the connector block signal wiring when hot-swapping
modules.
Operate Compact FieldPoint products at or below the
installation 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. Installation
categories establish standard impulse withstand voltage levels that
commonly occur in electrical distribution systems. The following is a
description of installation categories:
•
Installation 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 levels, special equipment, limited-energy parts of
equipment, circuits powered by regulated low-voltage sources, and
electronics.
•
Installation 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 (for example, 115 V for U.S. or 230 V for Europe).
Examples of Installation Category II are measurements performed on
household appliances, portable tools, and similar products.
•
Installation 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
1
Installation categories, also referred to as
measurement categories
, are defined in electrical safety standard IEC 61010-1.
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 equipment. Suitably rated measuring circuits may
be connected to the MAINS for measuring purposes.
