Sonel MRU-30 Manuale utente

MRU-30 –USER MANUAL

USER MANUAL

EARTH RESISTANCE METER

MRU-30

SONEL S. A.

Wokulskiego 11

58-100 Świdnica, Poland

Version 1.05 26.07.2021

MRU-30 –USER MANUAL

The MRU-30 meter is a modern, high quality, easy to use and safe measuring device. Please ac-

quaint yourself with the present manual in order to avoid measuring errors and prevent possible prob-

lems related to operation of the meter.

MRU-30 –USER MANUAL

TABLE OF CONTENTS

1Safety ................................................................................................................5

2Turning the meter ON and activating screen backlit....................................6

3Meter configuration .........................................................................................6

4Measurements..................................................................................................9

4.1 Measurement of AC+DC interfering (noise) voltages............................................... 9

4.2 Earth resistance measurement with 2-pole method (RE2P)................................... 10

4.3 Earth resistance measurement with 3-pole method (RE3P)...................................11

4.4 Earth resistance measurement with 4-wire method (RE4P)...................................15

4.5 Earth resistance measurement with 3-pole method with additional clamp (RE3P+C)...18

4.6 Earth resistance measurement with two-clamp method (2C)................................. 22

4.7 Calibration of the measurement clamp C-3............................................................ 24

4.8 Measurement of resistance of earth connection and equipotential bonding (RCONT)....26

4.9 Calibration of the test leads for RCONT measurement............................................. 28

4.10 Earth resistivity measurement (ρ) ..........................................................................29

5Memory of measurement results..................................................................33

5.1 Storing the measurement results in the memory ................................................... 33

5.2 Viewing memory data............................................................................................. 35

5.3 Deleting memory data............................................................................................36

5.3.1 Deleting cell data.........................................................................................................36

5.3.2 Deleting bank data.......................................................................................................37

5.3.3 Deleting the whole memory..........................................................................................39

6Data transmission..........................................................................................40

6.1 Computer connection accessories......................................................................... 40

6.2 Data transmission through USB port......................................................................40

7Firmware update ............................................................................................41

8Power supply of the meter............................................................................41

8.1 Monitoring the power supply voltage......................................................................41

8.2 Charging the rechargeable battery pack................................................................ 42

8.3 General principles of using Ni-MH batteries........................................................... 43

9Cleaning and maintenance ...........................................................................43

10 Storage............................................................................................................43

11 Dismantling and disposal .............................................................................44

12 Technical specifications ...............................................................................44

12.1 Basic data .............................................................................................................. 44

12.2 Additional data .......................................................................................................47

12.2.1 Influence of the serial interference voltage UZon earth resistance measurements for

methods RE3P, RE4P, RE3P+C, ρ................................................................................47

12.2.2 Influence of the auxiliary electrodes on earth resistance measurements for methods

RE3P, RE4P, RE3P+C, ρ..............................................................................................47

12.2.3 Influence of the interference current IZon the result of the earth resistance for method

RE3P+C.......................................................................................................................47

MRU-30 –USER MANUAL

12.2.4 Influence of interference current on the result of the earth resistance measurement for

two-clamp method (2C)...............................................................................................48

12.2.5 Influence of the relation of the resistance measured with clamp for the multiple earthing

branch to the resultant resistance (RE3P+C)............................................................... 48

12.2.6 Additional uncertainties in accordance with IEC 61557-5 (RE3P, RE4P)..........................48

13 Accessories ................................................................................................... 49

13.1 Standard accessories.............................................................................................49

13.2 Optional accessories..............................................................................................49

14 Manufacturer.................................................................................................. 50

15 Laboratory services ...................................................................................... 51

MRU-30 –USER MANUAL

1 Safety

The MRU-30 meter has been designed to carry out measurements which results determine the

safety conditions of the installation. Therefore, in order to provide conditions for correct operation and

the correctness of the obtained results, the following recommendations must be observed:

Before you proceed to operate the meter, acquaint yourself thoroughly with the present manual

and observe the safety regulations and specifications determined by the producer.

The MRU-30 meter has been designed for the purpose of measurements of earth connection and

equipotential bonding, and also ground resistivity, Any application that differs from those specified

in the present manual may result in a damage to the device and constitute a source of danger for

the user.

The device must be operated solely by appropriately qualified personnel with relevant certificates

to carry out measurements of electric installation. Operation of the meter realized by unauthor-

ized personnel may result in damage to the device and constitute a source of danger for the user.

Using this manual does not exclude the need to comply with occupational health and safety regu-

lations and with other relevant fire regulations required during the performance of a particular type

of work. Before starting the work with the device in special environments, e.g. potentially fire-

risk/explosive environment, it is necessary to consult it with the person responsible for health and

safety.

It is unacceptable to operate the following:

A damaged meter which is completely or partially out of order,

A meter with damaged test leads insulation,

A meter stored for an excessive period of time in disadvantageous conditions (e.g. excessive

humidity). If the meter has been transferred from a cool to a warm environment of a

high level of relative humidity, do not start doing measurements until the meter has

been warmed up to the ambient temperature (approximately 30 minutes).

Before measurements may commence, make sure the test leads are connected to the appropri-

ate measurement sockets.

The meter can’t be powered from other sources than those mentioned in this manual.

The meter’s inputs are electronically protected from power surge, as a result for example, of ac-

cidental connection to the power supply source:

- for all input combinations –up to 276 V for 30 seconds.

Manufacturer’s calibration doesn’t include the resistance of test leads. Displayed result is sum

of the measured object and the test leads resistance.

The device complies with the following standards: EN 61010-1 and EN 61557-1, -4, -5.

Note:

Manufacturer reserves the right to apply changes in the appearance, accessories and technical

parameters of the meter. Due to continuous development of the meter’s software, the actual ap-

pearance of the display, in case of some of the functions, may slightly differ from the display pre-

sented in this operating manual.

MRU-30 –USER MANUAL

2 Turning the meter ON and activating screen backlit.

Turn on the meter with button.

Short press button to turn the

screen backlight on; press the button

again to turn the backlight off.

Switch off the meter by pressing and

and holding button for approx. 2

sec.

Emergency

situations.

Pressing button for approx. 7

seconds will turn off the meter in case

of emergency.

3 Meter configuration

Turn on the meter by pressing and

keeping SET/SEL button pressed.

When the Fn screen is displayed use

and to set mains frequency –50 Hz or

60 Hz (50 Hz is set as default).

MRU-30 –USER MANUAL

Use and buttons to enter the

screen with audio message settings:

bEEP.

Use and buttons to turn the audio

messages ON ( ) or OFF ( ).

Press and to switch to auto off set-

ting screen (Auto-OFF): oFF

Use and to set the time period af-

ter which the meter will turn off automati-

cally (Auto-OFF): 300 s, 600 s, 900 s or

none (dashes - Auto-OFF is disabled).

This function turns off the meter automati-

cally after the certain (set by user) period

of time.

MRU-30 –USER MANUAL

Use and buttons to enter the

screen where the unit of length can be se-

lected: diSt.

Use and buttons to set the unit of

length: ‘m’(meter) or ‘ft’(feet) (‘m’is set

as default).

Use and buttons to enter the

screen with firmware update: USB UPdt.

Press ENTER to enter the update mode. The

update process is described in point 7.

After changing the parameters, you may exit SETUP menu:

Press ENTER button to memorize settings

(not applicable for Update screen)

or use ESC button to go to the measurement

screen without confirming the changes.

Altri manuali per MRU-30

Indice

Altri manuali Sonel Strumento di misura

Manuali Strumento di misura popolari di altre marche

Suaoki

Suaoki D40 Manuale utente

Elster

Elster BK-G1.6 Manuale utente

Endress+Hauser

Endress+Hauser Deltabar FMD71 Manuale

Duratool

Duratool D03128 Manuale utente

Vega

Vega VEGAPULS 65 Manuale utente

Tonghui

Tonghui TH2618B Manuale utente

Tenmars

Tenmars TM-801 Manuale utente

MSR

MSR 145 Manuale utente

TPS

TPS WP-82 Manuale utente

ELMETRON

ELMETRON CP-511 Manuale utente

PCB Piezotronics

PCB Piezotronics 003C30 Manuale utente

Tenma

Tenma 72-10465 Manuale utente

Endress+Hauser

Endress+Hauser Proline Promag 50 Specifiche tecniche

Siemens

Siemens SITRANS F Coriolis FCT030 Manuale elenco delle parti

KLINGER

KLINGER CMF V Series Manuale utente

EXFO

EXFO FTB-2 Manuale operativo e di manutenzione

Keysight

Keysight M8290A Manuale utente

ADTEK

ADTEK MW-5 Manuale utente