General Description; Overvoltage/Installation Category - Velleman DCM115 User Manual


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. Clamp jaws
2. Clamp trigger
3. Selection button
4. Display
3 ½ digits
"V" jack
5.
Insert the red (positive) test lead in this connector to measure voltage,
resistance and frequency.
"COM" jack
6.
Insert the black (negative) test lead.
"EXT" jack
7.
Jack for insulation tester

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. 01 – 06/08/2018
DCM115
6 ©Velleman nv