Instruction Manual

XL423 - XL424
EN - 3
1.2 DURING USE
Carefully read the herewith recommendations and instructions:
WARNING
Non compliance with warnings and/or instructions may cause damage to
the tester or its components or injure the operator.
During a measurement never touch any unused terminal.
1.3 AFTER USE
If you expect not to use the instrument for a long period of time remove the batteries
and strictly follow the indications at paragraph 9.2.
1.4 OVERVOLTAGE CATEGORIES - DEFINITIONS
EN 61010-1 (Safety requirements for electrical equipment for measurement, control and
laboratory use, Part 1: General requirements) defines what a measurement category
(usually called “overvoltage category”) is. At paragraph 6.7.4: Measuring circuits it says:
(OMISSIS)
Circuits are divided into the following measurement categories:
Measurement category IV is for measurements performed at the source of low
voltage installations.
Examples are electricity meters and measurements on primary overcurrent protection devices
and ripple control units.
Measurement category III is for measurements performed in the building
installation.
Examples are measurements on distribution boards, circuit breakers, wiring,
including cables, bus-bars, junction boxes, switches, socket-outlets in the fixed
installation, and equipment for industrial use and some other equipment, for
example, stationary motors with permanent connection to fixed installation.
Measurement category II is for measurements performed on circuits directly
connected to the low voltage installation.
Examples are measurements on household appliances, portable tools and similar
equipment.
Measurement category I is for measurements performed on circuits not directly
connected to MAINS.
Examples are measurements on circuits not derived from MAINS, and specially
protected (internal) MAINS-derived circuits. In the latter case, transient stresses are
variable; for that reason, the norm requires that the transient withstand capability of
the equipment is made known to the user.