•
Always be careful when working with voltages above 60 VDC or 30 VAC
rms. Keep your fingers behind the probe barriers at all times during
measurement.
•
Never perform resistance, diode or continuity measurements on live
circuits. Make sure all capacitors in the circuit are depleted.
6. General Description
Refer to the illustration on page 2 of this manual:
1.
NCV sensor
2.
Clamp jaws
3.
Flashlight
4.
NCV LED indicator
5.
Flashlight switch
6.
Clamp trigger
7.
Selection button
8.
Backlight button
9.
Display
3 ½ digits
10. Function buttons
11. Input jacks
7. Overvoltage/Installation Category
DMMs are categorized depending on the risk and severity of transient
overvoltage that might occur at the point of test. Transients are short-lived
bursts of energy induced in a system, e.g. caused by lightning strike on a
power line.
The existing categories according EN 61010-1 are:
A CAT I-rated meter is suitable for measurements on protected
CAT I
electronic circuits that are not directly connected to mains power, e.g.
electronics circuits, control signals...
A CAT II-rated meter is suitable for measurements in CAT I-
environments and mono-phase appliances that are connected to the
CAT
mains by means of a plug and circuits in a normal domestic
II
environment, provided that the circuit is at least 10 m apart from a
CAT III- or 20 m apart from a CAT IV-environment. E.g. household
appliances, portable tools...
A CAT III-rated meter is suitable for measurements in CAT I- and
CAT II-environments, as well as for measurements on (fixed) mono-
CAT
or poly-phased appliances which are at least 10 m apart from of a
III
CAT IV-environment, and for measurements in or on distribution level
equipment (fuse boxes, lighting circuits, electric ovens).
V. 03 – 05/07/2019
DCM120
6
©Velleman nv