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EX420-EU_ENG
V3.1
6/09
4
OVERVOLTAGE CATEGORY III
This meter meets the IEC 610-1-2001 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 400mV range
mA AC/DC
500mA 250V fast acting fuse
A AC/DC
20A 250V fast acting fuse(30 seconds max every
15 minutes)
Frequency, Resistance, Capacitance,
Duty Cycle, Diode Test, Continuity
250Vrms for 15sec max
Temperature
60V DC/24V AC
2.
USE EXTREME CAUTION
when working with high voltages.
3.
DO NOT
measure voltage if the voltage on the "COM" input jack exceeds 600V 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 covers 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.