HT instruments MPP300 - Manual (Page 5)

MPP300
EN - 3
1.2. DURING USE
Please carefully read the following recommendations and instructions:
CAUTION
 Failure to comply with the notes and/or instructions may damage the
instrument and/or its components or be a source of danger for the
operator
 The red flashing “POWER” LED indicates that the internal rechargeable
batteries are almost flat. In this case, connect the external power supply
as described in § 7.2

The IDC1, IDC2, IDC3 input connectors are type 4-pole type. Use only
clamps with 4-pin output connector or interpose adapter ACON3F4M
between the clamp output connector and the instrument input.
 The instrument maintains the data stored also in case of flat battery
 The instrument is particularly sensitive to ESD nearby and on the USB
port while it is operating; we recommend connecting the cables to the USB
port when the instrument is off
1.3. AFTER
USE
When measurements are completed, turn off the instrument by pressing and holding the
ON/OFF key for some seconds. If the instrument is not to be used for a long time, please
follow the instructions given in § 3.4
1.4. DEFINITION OF MEASUREMENT (OVERVOLTAGE) CATEGORY
Standard “IEC/EN61010-1: Safety requirements for electrical equipment for measurement,
control and laboratory use, Part 1: General requirements” defines what measurement
category, commonly called overvoltage category, is. § 6.7.4: Measured circuits, reads:
Circuits are divided into the following measurement categories:
 Measurement category IV is for measurements performed at the source of the low-
voltage installation
Examples are electricity meters and measurements on primary overcurrent protection
devices and ripple control units
 Measurement category III is for measurements performed on installations inside
buildings
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 standard requires that the transient withstand capability of
the equipment is made known to the user