Definition of installation categories :
• CAT IV:
Measurement category IV corresponds to measurements taken at the
source of low-voltage installations.
Example: power feeders
• CAT III:
Measurement category III corresponds to measurements on building
installations.
Example: industrial machinery or instrument power supplies
• CAT II:
Measurement category II corresponds to measurements taken on
circuits directly connected to low-voltage installations.
Example: household appliance and portable tool power supplies
• CAT I:
Measurement category I corresponds to measurements taken on
circuits not directly connected to the network.
Example: protected electronic circuits
1.2.1. Before use
• Comply with environmental and storage conditions.
• For your safety, before using the leads, systematically check they are is in
perfect working condition.
1.2.2. During use
As a safety measure, use only suitable leads and accessories supplied
with the instrument or approved by the manufacturer.
•
If the measurement category of the accessory is different from that of the
apparatus, the lowest category applies to the unit.
•
The probes used for network voltage measurement must have at least one
measurement category III according to IEC 61010-031 assigned and rated
voltage less than the voltage of the circuit to be measured.
•
Never exceed the protection limit values indicated in the specifications for
each type of measurement.
•
Before changing the function, disconnect the measurement leads from the
circuit measured.
•
Never measure resistances on a live circuit.
•
When the instrument is connected to the measurement circuits, never touch an
unused terminal.
1.3.
Safety features
•
It is impossible to access the battery or fuse compartment without first
disconnecting the measurement leads.
•
When measuring voltages greater than 50 V
flashes on the display.
•
When measuring voltages above 7 A, the sign blinks
an intermittent audible signal warns the user.
•
When there is a persistent overload on following ranges, an intermittent buzzer
indicates the risk of electric shock : VLOW Z, V
500 mA
(or 50 mA
DC
(or 50 mA
AC+DC
(except MX 23).
18
or 30 V
DC
AC+DC
: MX 24 and except MX 23), 500 mA
DC
: MX 24 and and except MX 23), 10 A
Chapter II
, the
symbol
AC
on the display and
, V
, ADP
, ADP
,
DC
DC
AC+DC
AC+DC
, 10 A
DC
AC+DC
Portable digital multimeters