During use. HT Instruments IRONMETER

IRONMETER

Please carefully read the following recommendations and instructions:

CAUTION

Failure to comply with the caution notes and/or instructions may damage the instrument and/or its components or be a source of danger for the operator.



Before activating the rotary switch, disconnect the test leads from the circuit being measured.



When the instrument is connected to the circuit being measured, do not touch any unused terminal.

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Do not measure resistance in case external voltages are present; even if the instrument is protected, an excessive voltage may cause malfunction.

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While measuring, if the value or the sign of the quantity being measured remain unchanged, check if the HOLD function is enabled.

USE



When measurement is complete, set the rotary switch to OFF to turn off the instrument.

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If the instrument is not to be used for a long time, remove the batteries.

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:

(OMISSIS)

Circuits are divided into the following measurement categories:



Measurement category IV is for measurements performed at the source of the lowvoltage 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.

EN - 3