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EX450V5.0V 10/06
3
OVERVOLTAGE CATEGORY III
This meter meets the IEC 610-1-95 standard for OVERVOLTAGE
CATEGORY III. Cat III meters are protected against overvoltage
transients in fixed installation at the distribution level. Examples
include switches in the fixed installation and some equipment for
industrial use with permanent connection to the fixed installation.
SAFETY INSTRUCTIONS
This meter has been designed for safe use, but must be operated
with caution. The rules listed below must be carefully followed for
safe operation.
1.
NEVER
apply voltage or current to the meter that exceeds the
specified maximum:
Input Protection Limits
Function Maximum
Input
V DC or V AC
1000V DC/750V AC, 200Vrms on
200mV range
mA AC/DC
200mA 250V fast acting fuse
A AC/DC
20A 250V fast acting fuse(30
seconds max every 15 minutes)
Resistance, Diode Test,
Continuity
250Vrms for 15sec max
2.
USE EXTREME CAUTION
when working with high voltages.
3.
DO NOT
measure voltage if the voltage on the "COM" input
jack exceeds 1000V above earth ground.
4.
NEVER
connect the meter leads across a voltage source
while the function switch is in the current, resistance, or diode
mode. Doing so can damage the meter.
5.
ALWAYS
discharge filter capacitors in power supplies and
disconnect the power when making resistance or diode tests.
6.
ALWAYS
turn off the power and disconnect the test leads
before opening the cover to replace the fuse or battery.
7.
NEVER
operate the meter unless the back cover and the
battery and fuse covers are in place and fastened securely.
8.
NEVER
look directly at the laser light source or aim the
pointer at an eye.