Datasheet

Overvoltage
category In brief Examples
CAT IV Three-phase at
utility connection,
any outdoor
conductors
•
Refers to the “origin of installation,” that
is, where low-voltage connection is made
to utility power
•
Electricity meters, primary overcurrent
protection equipment
•
Outside and service entrance, service
drop from pole to building, run between
meter and panel
•
Overhead line to detached building,
underground line to well pump
CAT III Three-phase
distribution,
including single-
phase commercial
lighting
•
Equipment in fixed installations, such as
switchgear and polyphase motors
•
Bus and feeder in industrial plants
•
Feeders and short branch circuits,
distribution panel devices
•
Lighting systems in larger buildings
•
Appliance outlets with short connections
to service entrance
CAT II Single-phase
receptacle
connected loads
•
Appliance, portable tools, and other
household and similar loads
•
Outlet and long branch circuits
–
Outlets at more than 10 meters (30 feet)
from CAT III source
–
Outlets at more that 20 meters (60 feet)
from CAT IV source
CAT I Electronic
•
Protected electronic equipment
•
Equipment connected to (source) circuits
in which measures are taken to limit
transient overvoltages to an appropriately
low level
•
Any high-voltage, low-energy source
derived from a high-winding resistance
transformer, such as the high-voltage
section of a copier
Table 1. Overvoltage installation categories. IEC 61010 applies to low-voltage
(< 1000 V) test equipment.
Built to with-
stand harsh
environments
with the highest
safety ratings
Rated all the way to CAT IV
ScopeMeter
®
test tools are rugged
solutions built for industrial troubleshoot-
ing. The new Fluke 190 Series II are
double-insulated floating oscilloscopes
safety rated for measurements in CATIII
1000V / CAT IV 600V environments.
Measure from mV to kV safely
Independent isolated inputs allow you
to make measurements in mixed circuits
having different ground references reduc-
ing the risk of accidental short circuits.
Conventional bench oscilloscopes with-
out special differential probes and isolation
transformers can only reference measure-
ments to line power earth ground.
With standard probes that cover a wide
application range from mV to kV, you’re
ready for anything from microelectronics to
heavy-duty higher voltage electrical appli-
cations.
IP-51 rated for harsh
environments
Rugged and shock-proof, ScopeMeter
®
portable oscilloscopes are built for dirty,
hazardous environments. With its sealed
case, it can endure
dust, drips, humidity
and airborne pollutants. Every time you
reach for ScopeMeter
®
portable oscillo-
scope you can be confident it will work
reliably wherever your work takes you.
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