Step Contact Voltage Measuring System MI 3295 Manual
Contents
1. Noise warning in this case a To view stored earth resistance or specific earth resistance results on PC they must be downloaded to the Meter first To download the results select Earth results in Synchronize menu After the results are downloaded the stored data in the Station will be automatically deleted For connection of the instruments see Figure 7 8 32 MI 3295 Step Contact Voltage Measuring System Data handling 8 Data handling 8 1 Memory Measured results together with all relevant parameters can be stored in the memory of Meter and Station a Step and Contact voltage measurements can be stored in the Meter a Earth resistance measurements can be stored in the Station and then be downloaded to the Meter a Specific earth resistance measurements can be stored in the Station and then be downloaded to the Meter a Values of generated currents are automatically stored in the Station s logger 8 1 1 Data structure The instrument s memory place is divided into 3 levels each containing 199 locations each The number of measurements that can be stored into one location is only limited by available memory The data structure field describes the identity of the measurement which object and location The measurement field contains information about type and number of measurements that belong to the selected structure element object and locations This organization helps to handle with data in a simple and effective manner T2. Step Contact Voltage Measuring System MI 3295 Instruction manual Version 1 3 Code no 20 751 785 My 7 METREL Distributor Manufacturer METREL d d Ljubljanska cesta 77 1354 Horjul Slovenia web site http www metrel si e mail metrel metrel si 2010 METREL The trade names Metrel Smartec Eurotest Autosequence are trademarks registered or pending in Europe and other countries No part of this publication may be reproduced or utilized in any form or by any means without permission in writing from METREL MI 3295 Step Contact Voltage Measuring System Table of contents Table of content T PICIOR N 5 2 Safety and operational considerations mnn nenea eneeeeneeennea nenea enneannneannaea nenea 6 21 WN ARMING SANG NOlES een s r nd S 6 2 2 Battery and charging Of MI 3295M cc eee aaa 6 2 2 1 New battery cells or cells unused for a longer period eee 8 2 3 Standards ADDI CO saiveiassinvaidvadseadinawiwsiceeaieusianaiacsiasaioniasauanniacaiaosianaieeniasiaaneatiorvines 8 3 Instrument description MI 3295M Meter cccscccceeseeceeeeeeeeseeeeeseeeeeseeeeeeeeeeenees 10 Sl IONE DANG IRI RER E ERE TRIER erate Re 10 D2 CONNECIOI DE iz eesti abona eae stiai E 11 SiO BACK Slee meon ura olari nd TOTEEN EEE 11 4 Instrument description MI 3295S Station mme nenea nenea nenea nenea nenaannanaaneaas 13 4 TON DaNEIsciseceti ati ei o citat Boti e act ro otet Gui
3. together with time and date in a separated part of the Station s memory See chapters 5 4 5 Synchronization and 7 2 4 Synchronization after the test for more information about the advantages of synchronized measurements The available place in the logger is shown in the right side of the Current Generator screen see Fig 6 2 Once the logger is full its content must be cleared 8 2 1 Clearing the logger content Select CLEAR CURRENT LOG in MEMORY menu A warning will be displayed CLEAR CURRENT LOG All saved currents will be lost Figure 8 12 Clear current logger Keys in Clear Logger menu TEST Confirms clearing of the complete logger content Exits back to main function menu without changes Figure 8 13 Clearing logger in progress 3 MI 3295 Step Contact Voltage Measuring System Data handling 8 3 Communication Stored results can be transferred to a PC from the Meter A special communication program on the PC automatically identifies the instrument and enables data transfer between the instrument and the PC There are two communication interfaces available on the Meter USB and RS232 The instrument automatically selects the communication mode according to detected interface USB interface has priority How to transfer stored data RS232 communication connect a PC COM port to the instrument PS 2 connector using the PS 2 RS232 serial communication cable USB communication connect a PC USB port to the
4. 6 3 Help SCIEENS camee sata aaasna meet ada adie ea e da e idea dea ali oala lada acid 21 G4 Contrast AGIUSHM CIS saersi eie iza deedee daia diac adaos d eul 21 Do He AIC TOMS Sle CLIO statia eaten enter atat atatea dean daar atatea dae aaa a tona nl 21 0 0 SE UNIRI ee oaie ve eee OEN 22 OOA LANGUI eae meri tere la nitel la ot ja ac is Daia at a ia 22 6 0 2 Inilal SeltiNgS emcee ceai ainu ale a an uta da lata tal te ta du 20 a iau aaa a 22 6 0 9 Pate GING TING is vina toscana re Ai dal ai ei die a i aride 22 064A OUIDUL DOWEL LANE scoica sista aa a ie iat it ata ca Ia Si 3 a i i 23 0 6 5 Alal sc scara ea e at dan at ot a gi a ian a ia i a lt i it dl d ai 23 7 Measurements stii ai ini aia ai ua atac ii a at a a nnmn 24 fai MNGORVAOL measuiremenilS sasa oase matinala loa a asia sila aleea 24 Peet General oreari piesei c ii oa ati eu 0 yeti Du ta cist ali olita tai ed be ucis 24 7 1 2 General on specific earth resistance ccccccccsecsececseeeeeeeseeeseceeeeeeeseeeeeeeseeeseeeaeeeeeees 25 TN MES UENEN sinuzite Cate ainu ada Div sau aula ata atat ans iun ea lada tt 25 Da Olean COMAC Vota GO sine inutila ial O iat nitel aha pla at nt te neutra 27 721 MNCCUON OF TEST CUI TENE seic 2252 taiate iama a a atata big i 27 MI 3295 Step Contact Voltage Measuring System Table of contents 7 2 2 Synchronization before the test recommended eee 28 7 2 3 Step voltage Contact voltage measurements eee eee eee 29 7 2 4 Synchroniz
5. 3295 Step Contact Voltage Measuring System Instrument description 3295S Station 4 Instrument description MI 3295S Station 4 1 Front panel 1 SA 250V Step Contact Voltage Measuring System Mains fuse Mains input Power On Off switch RS232 connector C1 H S ES C2 E HELP Function selector LCD CONTRAST MEM ESC Cursor and TEST keys TEST Figure 4 1 Front panel See chapter information For connection to mains cord 9 1 Fuse replacement for more For connection to the Meter Connection for auxiliary earthing probe Connection for voltage sense probe Connection for second voltage sense probe Connection for auxiliary earthing probe Help menus selects test function and settings LCD display with backlight Changes contrast Handling with memory Returns to previous screen Cursors Selects test parameters Starts measurement 13 MI 3295 Step Contact Voltage Measuring System Instrument description 3295S Station 4 2 Instrument set and accessories 4 2 1 Standard set 1p 1p 1p 1p 1p 1p Connection lead with crocodile clip red 1 m 1 pc Instruction manual S Instruction manual Calibration certificate LC 4 2 2 Optional accessories See the attached sheet for a list of optional accessories that are available on request from your distributor 14 MI 3295 Step Contact Voltage Measuring System MI 3295M Meter operation 5 MI 3295M Meter operation 5 1 Organization of display
6. 5 Step Contact Voltage Measuring System MI 3295S Station operation 6 6 4 Output power range POWER RANGE In this menu the power of the current ee generator can be set Figure 6 7 Output power menu Keys Cursor UP DOWN Selects appropriate option 50 75 100 TEST Sets selected power Returns to Settings main menu Note When the current generator is started the output power is automatically set to the available maximum If the conditions changed during the measurement the generator may switch off Possible reasons for switching off are a The output can become overloaded by high external earth currents In this case it is recommended to decrease the output power to 75 or 50 and restart the generator a The current stopped flowing abruptly If the stop was caused by disconnection of the leads it is not necessary to lower the power The generator can be restarted 6 6 5 Alarm An audible alarm warns the user that the BLED DISHELED current generator switched off due to overload or abrupt change of current The alarm can be activated deactivated in SUM Figure 6 8 Language selection Keys Cursor UP DOWN Enables disables the alarm TEST Confirms selected option Returns to Settings main menu Note a An enabled alarm helps to prevent from wrong interpretation of the Step and Contact voltage results The readings will be close to 0 V a pass if no test current is flowing 23 MI 329
7. 5 Step Contact Voltage Measuring System Measurements 7 Measurements 7 1 Theory of measurements 7 1 1 General on earthing An earthing electrode grid depleted into ground has a certain resistance depending on its size surface oxides on the metal surface and the soil resistivity around the electrode The earthing resistance is not concentrated in one point but is distributed around the electrode Correct earthing of exposed conductive parts assures that the voltage on them stays below dangerous level in case of a fault If a fault happens a fault current will flow through the earthing electrode A typical voltage distribution occurs around the electrode the voltage funnel The largest part of the voltage drop is concentrated around the earth electrode Fig 7 1 shows how fault step and contact voltages occur as a result of fault currents flowing through the earthing electrode grid in the ground Fault currents close to power distribution objects Substations distribution towers plants can be very high up to 200 kA This can result in dangerous step and contact voltages If there are underground metal connections intended or unknown the voltage funnel can get atypical forms and high voltages can occur far from the point of failure Therefore the voltage distribution in case of a fault around these objects must be carefully analyzed LA A Figure 7 1 Dangerous voltages on a faulty earthing system Standard IEC 61140 de
8. CONTACT WOLT 60 26 Function name Um 41 Ami u 1 yf T Result field pipi Um 41 Om E el Test parameter field Message field Figure 5 1 Typical function display 5 1 1 Battery indication The battery indication indicates the charge condition of battery and connection of external charger Battery capacity indication Low battery Battery is too weak to guarantee correct result Replace or recharge the battery cells Recharging in progress if power supply adapter is connected C Cot Warning a Ifthe batteries are removed for more than 1 minute a set time and date will be lost a the instrument will return to Initial settings 5 1 2 Warnings and messages In the message field warnings and messages are displayed H The Meter and Station are not synchronized Measurement is running consider displayed warnings Result s can be stored Measurement result is inside pre set limits PASS Measurement result is out of pre set limits FAIL 15 MI 3295 Step Contact Voltage Measuring System MI 3295M Meter operation 5 2 Backlight and contrast adjustments With the BACKLIGHT key backlight and LCD CONTRAST contrast can be adjusted as Figure 5 2 Contrast adjustment menu BACKLIGHT key Toggle backlight intensity level Lock high intensity backlight level until power is turned off or the ECD PIESRERIOr 5 key is pressed again Keep pressed for 2 s Bargraph for LCD contrast adju
9. Cleaning No special maintenance is required for the housing To clean the surface of both instruments Meter MI 3295M and Station MI 3295S use a soft cloth slightly moistened with soapy water or alcohol Then leave the instrument to dry totally before use Warnings a Do not use liquids based on petrol or hydrocarbons a Do not spill cleaning liquid over the instrument 9 3 Periodic calibration lt is essential that the test instrument is regularly calibrated in order that the technical specification listed in this manual is guaranteed We recommend an annual calibration Only an authorized technical person can do the calibration Please contact your dealer for further information 9 4 Service For repairs under warranty or at any other time please contact your distributor 39 MI 3295 Step Contact Voltage Measuring System Technical specifications 10 Technical specifications 10 1 Step voltage Contact voltage Measuring range Um 0 01 19 99 mV 0 01 mV 20 0 199 9 mV 200 1999 mV 2 of reading 2 dig 2 00 19 99 V 0 01 V 20 0 59 9 V Calculated Resolution Accuracy measuring range U 0 0 199 9 V calculated value 200 999 V Displayed Step Contact voltage is obtained on base of calculation Us Umeas Ifault gen Uc Umeas Ifauit gen laut selectable 10 A 200 kA Input resistance selectable 1 KQO 1 MO Noise cancelation DSP filtering 55 Hz 64 dB rejection of 50 60 Hz nois
10. IZED 6 Figure 7 11 Examples of synchronization screens NOT SYNCHRONIZED number of non synchronized results Note Q Synchronization of Step Contact voltage results can last up to several 10 seconds A bargraph is showing the progress S 7 3 Earth resistance 7 3 1 Earth resistance measurement Figure 7 12 Earth resistance screen Earth resistance measurements MI 3295 Step Contact Voltage Measuring System Measurements Connect C1 H test lead to current probe Connect S potential lead to potential probe Press the TEST key to perform the measurement Store the result with MEM key optional Connections for earth resistance measurement For connections see Figure 7 4 Figure 7 13 Example of earth resistance measurement result Displayed results for earth resistance measurement ARE RE IDE Earth resistance RD za aeaid Resistance of S potential probe S O Magadan Resistance of H current probe Notes a High resistance of S and H probes could influence the measurement results In this case the Probe warnings are displayed a High noise currents and voltages in earth could influence the measurement results The tester displays the Noise warning in this case a Probes must be placed at sufficient distance from the measured object a To view stored earth resistance or specific earth resistance results on PC they must be downloaded to the Meter first To download the results select Ea
11. Si 2mh 23 3 Laen LE HF Iflt 1 8kA l Figure 8 5 Example of recalled measurement result Keys in recall memory menu measurement results are displayed Cursor LEFT RIGHT Displays measurement results stored in selected location Cursor UP DOWN View all test parameters Exits back to measurement field 8 1 4 Clearing stored data Clearing complete memory content Select CLEAR ALL MEMORY in MEMORY menu A warning will be displayed CLEAR ALL MEMORY All saved results will be lost Figure 8 6 Clear all memory Keys in clear all memory menu TEST Confirms clearing of complete memory content Exits back to Settings main menu without changes CLEARING MEMORY 77 Ei Figure 8 7 Clearing memory in progress Clearing measurement s in selected location Select DELETE RESULTS in MEMORY menu 35 MI 3295 Step Contact Voltage Measuring System Data handling DELETE FESLILT gt DELETE FESULT Sa DELETE FESULT gt OBJECT Hl OBJECT Hl OBJECT HH gt LOCI al LOC1 ii L CI Hel gt Lote bi sa iii O Hos 3O O OOOO OOOO O CLEAR RESULTS Figure 8 8 Clear measurements menu data structure field selected Keys in delete results menu data structure field selected Cursor UP DOWN Selects location element Object Loc1 Loc2 Cursor LEFT RIGHT Selects number of selected location element 1 to 199 Exits back to Settings main menu Opens dialog for confirmation to clear result s in selecte
12. ation after the test recommended eee eee 30 Tad Eanes Onin ma i pa i ri nae tite a lie tie lilt aie bots it 30 7 3 1 Barth resistance measurements iata aa casa a dau ra a a ta al o a 30 7 3 2 Specific earth resistance measurement c eee eee eee eee aaa 31 9 Data NaNGIIIICjcicseiconsctinacacainasaoarieacaicigaciieaui EA A iaa Aaa aaa 33 ol MEMON ooro N d ei let dt lt it e atat it aia tt ti ta 33 Old Data STOCU E saca neatentie atatia ra a i tal Et at sous tea ca ital 33 6 1 2 SONNI SST FSS UES sie aia ae cata eat ve ua a oaia 3 Drac EE 34 Gel REGAINING MCSE CSUNG sait ipiai ooo sai de thee dea ie hae ie ook a ot a i 34 0 14 Gleanna stored Oaie sie cat aie oua aaa ca 05 a a 35 GZ Cumont LOGO EN sees iai art 30 gi e ia aiba aie Shuster Shorea bea ot 3 ees 37 8 2 1 Clearing the logger content eee eee eee eee aaa 37 8 3 COMIMURICaLUOI siana o iza sade ideaaa dadea aa aedea ai Ldaa aa ada aaa dea ae aa dia aaa ca dadea 38 9 Mantenan E sro EE EEE a E ata iat a iati carat astia ata 39 921 FUSeTEeplacemeni si saca patat iat p t aa at adi ta li la il ln d ta at lt dt a a 39 9 2 CACAIMNG inscenat eee Bea iii Er iii Brat li na il nori Ge li bat i eta Me e Di Aia 39 9 3 Periodic calibration NE 39 g4 SENCO sait atasa oieri bora da arta n v zu 0 aia tao ara tuia oaia tat 39 10 Teennical speciiiCati OnSite ati luati pati lati ala tat ital la ii AEE 40 10 1 Step Voltage Contact voltage cireasa ai na
13. d location Keys in dialog for confirmation to clear results in selected location TEST Deletes all results in selected location Exits back to delete results menu without changes Clearing individual measurements Select DELETE RESULTS in MEMORY menu DELETE FESULTE OBJECT 81 gt Ha i der CONTACT WOLT Figure 8 9 Menu for clearing individual measurement measurement field selected Keys in delete results menu data structure field selected Cursor UP DOWN Selects location element Object Loc1 Loc2 Cursor LEFT RIGHT selects number of selected location element 1 to 199 TEST Enters measurements field Exits back to Settings main menu Keys in delete results menu measurements field selected Cursor LEFT RIGHT Selects measurement Opens dialog box for confirmation to clear selected measurement Exits back to data structure field Keys in dialog for confirmation to clear selected result s TEST Deletes selected measurement result Exits back to measurements field without changes DELETE FESULTS III OBJECT ae Loci eel DELETE FESULTS III OBJECT aai Loci ai gt Mo 272 gt Ho STEP WOLT 1 1 CLEAR RESULT Figure 8 10 Dialog for confirmation Figure 8 11 Display after measurement was cleared 36 MI 3295 Step Contact Voltage Measuring System Data handling 8 2 Current Logger If the Meter and Station are synchronized the values of generated currents are stored
14. e Test terminals Test connector Meter 10 2 Current Measuring range 0 00 9 99 A 0 01 A 3 of reading 5 dig 10 0 99 9 A 3 of reading 3 dig Current generator 55 A max Test voltage lt 55 V Test frequency 55 Hz Test terminals C1 H C2 E 10 3 Resistance to earth Measuring range 0 001 1 999 Q 0 001 Q 2 00 19 99 O 0 01 O 2 of reading 5 dig 20 0 99 9 Q 100 0 199 90 5 of reading Open circuit voltage e eee lt 50 VAC ESI CURT EN lEcasieciseas aceata Si aicea le ia ia ai lt 7 5 A MI 3295 Step Contact Voltage Measuring System Technical specifications Test signal frequency ccccccsecseeceeeeeeeseees 55 Hz Influence of probe resistance lt 10 of reading 10 digits Rc RP max 10 Q 100 R or 2 KQ whichever is lower Automatic test of probe resistance yes Automatic detection of voltage noise Test terminals S ES C1 H C2 E 10 4 Specific earth resistance Measuring range Om Resolution 2m 0 00 9 99 10 0 99 9 100 999 Calculated value consider accuracy of Resistance to earth function 1 00k 9 99k 0 01k 10 0k 99 9k Wenner method principle with equal distances between test probes p 2 r distance R 10 5 General data Station Rated supply voltage c 230 V AC 10 50 or 60 Hz Max power consumption 750 VA Overvoltage category CAT Il 300 V M
15. easuring category eee CAT IV 50 V Protection classification ccccceceeees Class General protection of the instrument FS E A EAE an int ta eat aa T5A 250 V 5 mm x 20 mm Pollution degree 3 Degree of protection c eee IP 30 IIS DIA asezare aia tat iii E isa teh sates 128 x 64 dots matrix display with backlight MOMO ici aurii eter a c uta ia ue 1000 memory locations GULER logger srpa eseon I 24 hours min Communication interface RS232 for communication with Meter only Dimensions WXNX ccceceeeeeeeeeeeeees 56 3 cm x 27 5 cm x 25 7 cm YVON sasea sai ieri ie og eisai eas 29 5 kg without accessories Meter Power supply voltage 00eeeeeee 9 Voc 6 x 1 5 V battery or accu size AA OPSION eine E tii c i a typical 12h Charger socket input voltage 12 V 10 Charger socket input current 400 mA max Battery charging current 250 mA internally regulated 41 MI 3295 Step Contact Voltage Measuring System Technical specifications Measuring category cccccceeeseeeeeeees CAT IV 50 V Protection classification ccceceees double insulation Pollution degree nenea 2 Degree of protection cccceeceeeeeees IP 40 DIS UA 0 ae aia ei alo ele leat ana 128 x 64 dots matrix display with backlight MEMO sas ceczeadasecieassneusasei taiA dlei dtae aes 1500 memory l
16. ee ile nd tb adi tere 13 4 2 Instrument Set and accessories eee eee 14 Zale SAIC ANG Se asia iata nai natale o da adela ad ata o Aaaa A p Are 14 422 OpUONal accessOIlleS a aaa inune tut sati aie pu dica nai dainui acd a debloca 14 5 MI3295M Meter operation lt cmscnnii aia caen dida datata doilea uit dai oa ala aula te 15 Si ORGANIZATION OF CISDlaVicss sti saizeci tele la lin alina lira lis lia alatdearwatdtarwreleboresa 15 Ole Balen IMGICQUON esec asia oua d le ca aa si a ca ali ct a ti rd ala Da oa atita i cae 15 5 1 2 Wa inihgsana messages e oa oaia aia pt c i dt letal at a 15 5 2 Backlight and contrast adjustments c eee eee eee 16 DO FUNCUOM SEIS CUO aaa inu 20 a 0 a ia Di 0 Do ano note iz 16 Te OCUN S eius te ter set tot ocna ital cata ai ct til eta il ee ee ee ee 16 DAL LEAGUE se iesite ema oaie Stirea ce pe ia e lite tt ainu at te ur o at sl daca a ee 17 S42 ICID SClCCMS aci el iti aa aaa dati ta l li a it i a al au 17 OO NAINA GOUIING S ienes Dei egirl taia ate ta Sa Datu alea iti dual oala aa tite 17 S44 Date and UME serienr Pate aa ul aaa dea ada as Dada years i c ad o dar da ura 18 5 45 SYNCMIONIZALON acusticii zu iattoza a a teo alla a at ada 18 6 MI 3295S Station Operation cccccccseseecesseccesseeceseeeceseeeeeseesenseenenseeeeasesonseesensesees 20 6 1 Organization OF CISDIAY S siessen EE E ELIA 20 62 Wamngsand Messages scania ea a a oa leafa Cafea teats 20
17. emory effect As a result the instrument operation time can be significantly reduced Recommended procedure for recovering battery cells Procedure Notes gt Completely charge the battery At least 14 h with in built charger Use the instrument for normal testing until gt Completely discharge the battery the unit displays the Bat symbol on screen gt Repeat the charge discharge cycle for Four cycles are recommended at least twice Complete discharge charge cycle can be performed automatically for each cell using external intelligent battery charger Notes a The charger in the instrument is a pack cell charger This means that the battery cells are connected in series during the charging The battery cells have to be equivalent same charge condition same type and age a One different battery cell can cause an improper charging and incorrect discharging during normal usage of the entire battery pack it results in heating of the battery pack significantly decreased operation time reversed polarity of defective cell a If no improvement is achieved after several charge discharge cycles then each battery cell should be checked by comparing battery voltages testing them in a cell charger etc It is very likely that only some of the battery cells are deteriorated a The effects described above should not be confused with the normal decrease of battery capacity over time Battery also loses some capacity wh
18. en it is repeatedly charged discharged This information is provided in the technical specification from battery manufacturer 2 3 Standards applied The Step Contact Voltage Measuring System MI 3295 is manufactured and tested according to the following regulations listed below Electromagnetic compatibility EMC IEC EN 61326 1 Electrical equipment for measurement control and laboratory use EMC requirements Part 1 General requirements Class B Hand held equipment used in controlled EM environments IEC EN 61326 2 2 Electrical equipment for measurement control and laboratory use EMC requirements Part 2 2 Particular requirements Test configurations operational conditions and performance criteria for portable test measuring and monitoring equipment used in low voltage distribution systems MI 3295 Step Contact Voltage Measuring System Safety and operational considerations Safety LVD IEC EN 61010 1 Safety requirements for electrical equipment for measurement control and laboratory use Part 1 General requirements IEC EN 61010 Safety requirements for hand held probe assemblies for electrical 031 measurement and test Functionality HD 637 S1 Power installations exceeding 1 kV a c ANSI IEEE Std 81 IEEE Guide for Measuring Earth Resistivity Ground Impedance and Earth Surface Potentials of a Ground System RAT 2008 Spain High Voltage regulation MI 3295 Step Contact Voltage Measuring System Instrument d
19. escription 3295 M Meter 3 Instrument description MI 3295M Meter 3 1 Front panel RR N MI Rovere UE aS Bo O on Ay m oy f f 4 f d f Figure 3 1 Front panel Legend 1 ESC Returns to previous menu 2 MEM Handling with memory 3 Cursor and TEST keys Cursors Selects test parameters TEST Starts stops measurement 4 BACKLIGHT CONTRAST Changes backlight level and contrast 5 LCD LCD display with backlight Switches the instrument power on or off 6 ON OFF The instrument automatically turns off 15 minutes after the last key was pressed 7 8 Function selector Selects test function and settings 10 MI 3295 Step Contact Voltage Measuring System Instrument description 3295M Meter 3 2 Connector panel Figure 3 2 Connector panel Legend 1 O1 amp G DO Test connector Warning Maximal allowed voltage between test terminals and ground is 50 V Maximal allowed voltage between test terminals is 100 V Power supply socket PS 2 connector for RS232 communication Protection cover USB connector 3 3 Back site Figure 3 3 Back panel Legend 1 2 3 Battery compartment cover Information label Fixing screws for battery compartment cover 11 MI 3295 Step Contact Voltage Measuring System Instrument description 3295M Meter Figure 3 4 Battery compartment Legend 1 Serial number label 2 Battery cells size AA 3 Battery compartment 12 MI
20. fines following maximum allowed time contact voltage relations Maximum time of exposure Voltage Uc lt 50 Vac or lt 120 Voc Uc lt 115 Vac or lt 180 Voc lt 0 2 s Uc lt 200 Vac Uc lt 250 Vac Table 13 Maximum time durations vs fault voltage For a longer exposure the touch voltages must stay below 50 V 24 MI 3295 Step Contact Voltage Measuring System Measurements 7 1 2 General on specific earth resistance The specific earth resistance soil resistivity is measured to determine the characteristic of the soil The measurement is carried out in order to assure more accurate calculation of earthing systems e g for high voltage distribution columns large industrial plants lightning systems etc The results are used to properly dimension earthing systems size depth number and position of earthing rods Specific Earth Resistance value is expressed in QM 7 1 3 Measurement During the measurement a test current is injected into the earth through an auxiliary probe The resistance of the auxiliary probe should be as low as possible in order to inject a high test current The resistance can be decreased by using more probes in parallel or using an auxiliary earthing system as the auxiliary probe A higher injected current improves the immunity against spurious earth currents Step voltage The measurement is performed between two ground points at a distance of 1 m as shown on Fig 7 2 The 25 kg measuring probes
21. g generation of current Note a The output power is set automatically to its available maximum In case of troubles generator switches off refer to chapter 6 6 4 Output power range a Incompletely unwound measuring cable can influence on size of generated test current coil impedance a Usually the resistance of auxiliary probe limits the injected current The injected current can be increased by placing more probes in parallel 7 2 2 Synchronization before the test recommended Before starting with the Step and Contact voltage measurements it is recommended to synchronize the Meter and the Station The synchronization sets the same date and time in both units Therefore the measured voltages can be correctly scaled after the measurements If the current is generated during the synchronization its value of is also send to the Meter For more information see chapter 5 4 5 Synchronization a Connect Meter to the Station with the RS232 cable a On Meter select the TIME CURRENT option in SoQ lenlitel 45 menu and confirm Follow the information on the Meters LCD If the synchronization succeeded a confirmation beep will follow after short and MESSAGES Connections for synchronization RS 232 Figure 7 8 Connection of the instruments during synchronization Note a The measurements can be carried out without synchronization In this case the measuring current must be set changed manually If the i
22. he main advantages of this system are a Test results can be organized and grouped in a structured manner a Simple browsing through structures and results a Test reports can be created with no or little modifications after downloading results to a PC RECALL RESULTS OBJECT eal LOCi l Loc Hai RECALL RESULTS OBJECT eal gt Ho TAT STEP WOLT Figure 8 1 Data structure and measurement fields Data structure field a SE Memory operation menu OBJECT H l LOC AR Data structure field LOLS El a 1 level ORJECT Bi OBJECT Default location name object and its successive numee a 2 level LUA Be LOC1 Default location name and its successive number a 3 level LOL HE LOC2 Default location name and its successive number a 001 No of selected element 33 MI 3295 Step Contact Voltage Measuring System Data handling Measurement field Ho 1 No of measurements in selected location No of measurements in selected location Ho r C13 No of measurements in selected location and its sub locations Ho fee No of selected test result No of all stored test results in selected location STEF MULT Type of stored measurement in the selected location 8 1 2 Storing test results After the completion of a test the results and parameters are ready for storing Ei icon is displayed in the information field By pressing the MEM key the user can store the results Figure 8 2 Save test menu Display i
23. instrument Internal circuit controls charging assuring maximum battery lifetime The power supply socket polarity is shown in figure 2 2 Figure 2 2 Power supply socket polarity The instrument automatically recognizes the connected power supply adapter and begins charging Symbols Indication of battery charging i Figure 2 3 Charging indication a A Before opening battery compartment cover disconnect all measuring accessories connected to the instrument and switch off the instrument a Do not charge alkaline battery cells a Insert cells correctly otherwise the instrument will not operate and the batteries could be damaged a Remove all battery cells from the battery compartment if the instrument is not used for a long period of time a Take into account handling maintenance and recycling requirements that are defined by related regulations and manufacturers of alkaline or rechargeable batteries a Use only power supply adapter delivered from the manufacturer or distributor of the test equipment to avoid possible fire or electric shock MI 3295 Step Contact Voltage Measuring System Safety and operational considerations 2 2 1 New battery cells or cells unused for a longer period Unpredictable chemical processes can occur during charging of new battery cells or cells that were unused for a longer period more than 3 months NiMH and NiCd battery cells are affected to capacity degradation sometimes called as m
24. instrument USB connector using the USB interface cable Switch on the PC and the instrument Run PCSW HVLink PRO The PC and the instrument will automatically recognize each other The instrument is prepared to download data to the PC The program HVLink PRO is a PC software running on Windows XP Windows Vista and Windows 7 Read the file README_HVLinkPRO txt on CD for instructions about installing and running the program Note a USB drivers should be installed on PC before using the USB interface Refer to USB installation instructions available on installation CD 38 MI 3295 Step Contact Voltage Measuring System Maintenance 9 Maintenance Unauthorized persons are not allowed to open the instruments There are no user replaceable components inside the instrument except the battery under rear cover of Meter MI 3295M See chapter 2 2 Battery and charging of MI 3295M 9 1 Fuse replacement There is a fuse on the front cover of the MI 3295S Station a TSA 250 V 5 mm x 20 mm This fuse prevents from danger in case of a fault inside the instrument Warnings a A Disconnect all measuring accessories switch off the instrument and disconnect mains cord before opening the cover of fuse holder hazardous voltage inside a Replace blown fuse with original type only otherwise the instrument may be damaged and or operator s safety impaired Position of a fuse can be seen in Figure 4 7 in chapter 4 7 Front panel 9 2
25. nce For the specific earth resistance the test current is injected through two current probes C1 H and C2 E The voltage probes S and ES must be placed between the current probes equidistance a between probes must be considered Using different distances between the test probes means that the material at different depths is measured By increasing the distances a a deeper layer of ground material is measured More information about measuring earth resistance can be found in the METREL handbook Guide for testing and verification of low voltage installations H o m l CEE py J 7 D x gt Pi W Figure 7 5 Specific earth resistance measurement 7 2 Step and Contact voltage 7 2 1 Injection of test current Before starting the Step or Contact voltage measurements the test current must be injected in the earth with MI 3295S CURRENT GEN 15 493 A Figure 7 6 Current generator screen Connect C2 test lead to the main earthing point Place the earth probe Connect C1 test lead to the earth probe or another auxiliary earthing point Select el9ls1s13 acela function Press the TEST key to start the generation of the current Check the value of the current 27 MI 3295 Step Contact Voltage Measuring System Measurements Connections for step and contact voltage measurement For connections of the Station see figures 7 2 and 7 3 CURRENT GEN 12 45 i Figure 7 7 Example of the display durin
26. nformation FREE 39 1 Memory available for storing results Keys in save test menu data structure field Cursor UP DOWN selects the location element Object Loc1 Loc2 Cursor LEFT RIGHT Selects number of selected location element 1 to 199 coi test results to the selected location and returns to the measuring menu ESC _ Exits back to the measuring menu without save Notes a The instrument offers to store the result to the last selected location by default a If the measurement is to be stored to the same location as the previous one just press the MEM key twice 8 1 3 Recalling test results In MEMORY menu select RECALL RESULTS RECALL RESULTS gt OBJECT Gal FECALL RESULTS OBJECT ae gt Hou TAT STEP VOLT Figure 8 3 Recall menu data structure Figure 8 4 Recall menu measurements field selected field selected 34 MI 3295 Step Contact Voltage Measuring System Data handling Keys in recall memory menu data structure field selected Cursor UP DOWN Selects the location element Object Loc Loc2 Cursor LEFT RIGHT Selects number of selected location element 1 to 199 TEST Confirms selection and enters measurements field ESC Exits back to main function menu Keys in recall memory menu measurements field selected Cursor LEFT RIGHT Selects the stored measurement TEST Displays measurement results Exits back to data structure field 13 38 V Une
27. njected current is changing during the test the Iser parameter must be adjusted manually The measurement results cannot be corrected after the measurement 28 MI 3295 Step Contact Voltage Measuring System Measurements 7 2 3 Step voltage Contact voltage measurements While the Station injects the measuring current into earth the Step or Contact voltage tests with the Meter can be carried out CONTACT VOLT 13 31 lflt Figure 7 9 Steo and Contact Voltage screens lflt Test parameters for Step Contact voltage measurement flt Maximum expected fault current 10 A 200 kA Test current manual set 0 20 A 50 A or uploaded from Station Input resistance 1 MO 1 KQ A A A E Limit step voltage 25 V 50 V Step or Contact voltage measurements Select SULAA My or amp e iy ve dei function Set test parameters limits optional For Step voltage place the test electrodes see chapter 7 1 2 Measurement for more information For Contact voltage place one test electrode and connect accessible metal part see chapter 7 1 2 Measurement for more information Connect the test leads to the instrument Press the TEST key to perform the measurement Store the result by pressing the MEM key optional a The measurements can be carried out without synchronization In this case the measuring current must be controlled and set changed manually The results cannot be corrected after the measurement Co
28. nnections for step and contact voltage measurement For connections see figures 7 2 and 7 3 CONTACT VOLT 13 33 STEP WOLT 13 34 Um 41 Amb i IAern igor EGA l Figure 7 10 Examples of step and contact measurement results Um 42 Tml fi Aar Displayed results for step and contact voltage measurements E calculated Step or Contact voltage Olga AR measured Step or Contact voltage 29 MI 3295 Step Contact Voltage Measuring System Measurements Note a For dry soil or concrete floor a damp cloth or a film of water should be placed between the probe and the floor a Itis possible to work with more Meters at the same time 7 2 4 Synchronization after the test recommended lf the Meter and Station were synchronized during the measurements they should be synchronized again after finishing the tests In this step the values of generated currents measured with the Station are downloaded to the Meter On base of the real generated current data the correction of measured results in the Meter is done For more information see chapter 5 4 5 Synchronization Connect Meter to the Station with the RS232 cable On Meter select STEP CONTACT VOLT in AANA A menu and confirm Follow the information on the Meter LCD If the synchronization succeeds a confirmation beep will follow the and messages Connections for synchronization For connection of the instruments see Figure 7 8 3 HCHEOMI ZE BEE iei a laga HOT SYNCHRON
29. ocations Communication interface RS232 USB Dimensions WXNX cccececeeeeeeeeeeeees 23 cm x 10 3 cm x 11 5 cm Weight eee eee 1 3 kg with batteries Environmental conditions Reference temperature range 10 C 30 C Reference humidity range 35 65 RH Operation conditions Working temperature range 0 C 40 C Maximum relative humidity 85 RH 0 C 40 C non condensing Storage conditions Temperature range 10 C 60 C Maximum relative humidity 90 RH 10 C 40 C 80 RH 40 C 60 C Accuracies apply for 1 year in reference conditions Temperature coefficient outside these limits is 0 2 of measured value per C and 1 digit 42
30. rent generator is on VOLT Meter for calculation of Step voltage or Contact voltage Station will be uploaded to the Meter 18 MI 3295 Step Contact Voltage Measuring System MI 3295M Meter operation Note Q The main purpose of the Time Current synchronization is to enable a correction of the step and contact voltage results after the test During the test the step and contact voltage results are calculated on base on the set Iser in the Meter After the test the results made with the Meter can be updated with the real generator currents lcen that were measured at the same time with the Station The stored Ustep and Ucontact values are then corrected according to the following formula U a Gen actually _ generated STEPnew STEPold ooy SET U U Gen actually _ generated CONTnew CONTold oro SET The synchronization is active for 24 h If the date time are changed at the Meter or the Station the synchronization of time and data will be lost The Current logger must be cleared before it can be proceeded with the measurements Before clearing it the content can be downloaded to the Meter If there is no synchronization between both units the H icon is displayed in the Meter measuring screen 19 MI 3295 Step Contact Voltage Measuring System MI 3295S Station operation 6 MI 3295S Station operation 6 1 Organization of displays Function name rO 3052 Result amp Sub result field korgi Fi
31. res Bit Figure 6 1 Typical display in earth ___ resistance function message lel Function name 2 4m Test parameter field O 4 30m Result amp Sub result field Figure 6 2 Typical display in Reign Rr Bi specific earth resistance function Message field Function name Result field Message field Figure 6 3 Typical display in pa current function za Remained place in current logger 6 2 Warnings and messages Before and during the measurement the instrument performs different tests to ensure safety and to prevent from damaging it These safety tests include checking for any external voltage or improper loading of test terminals If a problem is detected an appropriate warning message will be displayed Warnings and protective measures are described in this chapter CURRENT GEM GG SI Voltage between test terminals C1 H and C2 E is higher than ur 1 OVO abe allowed gt 10 V Disconnect the test leads and check why an external voltage was detected A CURRENT Er PIETE E Output was overloaded or test current abruptly fall down Current generator was Overload can be caused by high spurious earth current In this switched off Bre case it is recommended to decrease the output power See Abrutt change of eri current chapter 6 6 4 Outout power range for more information CURRENT GEN Gate Output current is too low A too low current can be caused Generated current too because of bad connection or high p
32. robe resistance connections to earth 20 MI 3295 Step Contact Voltage Measuring System MI 3295S Station operation CURRENT GEN DAF Date time was changed in the Station and consequentially LOGGED CURRENTS AUST the synchronization between Station and Meter is lost The nore Sue be Current logger must be cleared Before clearing it its content ti Alia TSCA e can be downloaded to the Meter In the message field warnings and messages are displayed Output power is not set to maximum High electrical noise was detected during measurement Results may be impaired High resistance of current c and or voltage p probes Results may be impaired Result s can be stored 6 3 Help screens H Ea Measurement is running consider displayed warnings Same as in MI 3295M see chapter 5 4 2 Help screen The help screens can be accessed with the HELP key 6 4 Contrast adjustments With the LIGHT key contrast can be LCD CONTRAST adjusted IE EP Figure 6 4 Contrast adjustment menu Keys for contrast adjustment Cursor LEFT RIGHT Sets contrast TEST Accepts new contrast Exits without changes 6 5 Function selection For selecting test function the FUNCTION SELECTOR shall be used Selects test measurement function a lt EARTH RE EARTH p gt earth resistance Function selector a lt CURRENT GEN gt generation of measuring current a lt SETTINGS gt settings Cursor UP DOWN Selects sub function in
33. rth results in Synchronize menu After the results are downloaded the stored data in the Station will be automatically deleted For connection of the instruments see Figure 7 8 7 3 2 Specific earth resistance measurement Figure 7 14 Specific earth resistance screen Specific earth resistance measurements Select Vaasa function using the function selector switch Select aaia subfunction using the cursor UP DOWN keys Select test parameter using the cursor LEFT RIGHT keys Set distance a using the cursor UP DOWN keys Connect C1 H and C2 E test leads as current probes Connect S and ES test leads as potential probes Press the TEST key to perform the measurement Store the result with MEM key optional E E E E E E E Q 31 MI 3295 Step Contact Voltage Measuring System Measurements Connections for specific earth resistance measurement For connections see Figure 7 5 Figure 7 15 Example of specific earth resistance measurement result Displayed results for earth resistance measurement 0 PERETI Specific earth resistance R Deerin Resistance of sum S ES of potential probes RO oni Resistance of sum C1 H C2 E of current probes Notes a High resistance of current and potential probes could influence the measurement results In this case the Probe warnings are displayed a High noise currents and voltages in earth could influence the measurement results The tester displays the
34. selected measurement function Cursor LEFT RIGHT Selects the test parameter to be modified Keys in test parameter field Cursor UP DOWN Changes the selected parameter 21 MI 3295 Step Contact Voltage Measuring System MI 3295S Station operation 6 6 Settings Different instrument options can be set in the SETTINGS menu Options are SETTINGS BELLIS a Selection of language i initi INITIAL SETTINGS a Setting the instrument to initial values POWER RANGE a Setting the output power of the MEMORY generator i a Setting the alarm a Recalling and clearing results a Setting date and time Figure 6 5 Options in Settings menu Keys Cursor UP DOWN Selects appropriate option TEST Enters selected option Exits back to main function menu 6 6 1 Language Same as in MI 3295M see chapter 5 4 7 Language 6 6 2 Initial settings IHITIAL SETTINGS Selecting this option will allow the user to reset the instrument settings and measurement parameters and limits to the initial factory settings set to default E YES Figure 6 6 Initial settings screen Keys Cursor LEFT RIGHT Selects Yes or No TEST Restores default settings if Yes is selected Exits back to Settings main menu without changes Initial settings are Instrument setting Default value Default value English Disabled 100 6 6 3 Date and time Same as in MI 3295M see chapter 5 4 4 Date and time 22 MI 329
35. simulates the feet The voltage between the probes is measured by a voltmeter with an internal resistance of 1 kQ that simulates the body resistance A Figure 7 2 Step voltage measurement Contact voltage The measurement is performed between an earthed accessible metal part and ground as shown on Fig 7 3 The voltage between the probes is measured by a voltmeter with an internal resistance of 1kQ that simulates the body resistance 25 MI 3295 Step Contact Voltage Measuring System Measurements C2 h Figure 7 3 Contact voltage measurement As the test current is usually only a small fraction of the highest fault current the measured voltages must be up scaled according to following equation Uso U astazi a Gen WIG ta a cae calculated step or contact voltage in case of fault current U Measured Measured voltage during the test at i sasa maximal earth current in case of a fault E T TO injected test current Earth resistance For the earthing resistance test a voltage and current probe serves as auxiliary earth are used Because of the voltage funnel it is important that the test electrodes are placed correctly More information about measuring earth resistance can be found in the METREL handbook Guide for testing and verification of low voltage installations Figure 7 4 Earth resistance measurement 26 MI 3295 Step Contact Voltage Measuring System Measurements Specific earth resista
36. software package MI 3295 Step Contact Voltage Measuring System Safety and operational considerations 2 Safety and operational considerations 2 1 Warnings and notes In order to reach high level of operators safety while carrying out various tests and measurements using the Step Contact Voltage Measuring System as well as to keep the equipment undamaged it is necessary to consider the following general warnings a A Warning on the instrument means Read the Instruction manual with special care to safety operation The symbol requires an action a If the test equipment is used in a manner not specified in this user manual the protection provided by the equipment might be impaired a Read this user manual carefully otherwise use of the instrument may be dangerous for the operator or for the instrument a All normal safety precautions have to be taken in order to avoid risk of electric shock when working in the area of distribution systems a Do not use the instrument and accessories if any damage is noticed a Service intervention or adjustment and calibration procedure is allowed to be carried out only by a competent authorized person a Use only standard or optional test accessories supplied by your distributor Meter MI 3295M a Instrument contains rechargeable NiMh battery cells The cells should only be replaced with the same type as defined on the battery placement label or in this manual Do not use standard alkaline batter
37. stment is displayed Keys for contrast adjustment Cursor LEFT RIGHT Sets contrast TEST Confirms new contrast Exits without changes 5 3 Function selection For selecting function main menus the FUNCTION SELECTOR shall be used Selects test measurement function Function a lt STEP VOLT gt step voltage test selector a lt CONTACT VOLT gt contact voltage test a lt SETTINGS gt settings synchronization 5 4 Settings Different instrument options can be set in the SETTINGS menu Options are a Selection of language E IEEE a a Help screens SYNCHRONIZE a Synchronization with the Station E E a Setting the instrument to initial values i a Recalling and clearing stored results Figure 5 3 Settings menu a Setting date and time Keys Cursor UP DOWN Selects appropriate option TEST Enters selected option 16 MI 3295 Step Contact Voltage Measuring System MI 3295M Meter operation 5 4 1 Language SELECT LANGUAGE ENGLISH Language can be set in the SELECT SLOVENSKO LANGUAGE menu ESPANOL i Figure 5 4 Language selection Keys Cursor UP DOWN Selects language TEST Confirms selected language Returns to Settings main menu 5 4 2 Help screens The help screens contain basic schematic connection diagrams and information about DTE eal the instrument ae ems Figure 5 5 Example of help screen Keys Cursor LEFT RIGHT Selects next previous help screen Re
38. t aaa al a Dau toli dada a dute dala dada ada lat ae e 40 102 Cune en seoadenaipicaa aie aie ada auda cian aces da sia aaind aa aaa ile esoaa des aie dania iad sai aaa sa Bate 40 10 3 Resistance T0 eano o ateu ta tea ou odaia te eat a aaa cad 40 10 4 Specie earth tesist liGeisccai ie cozi a tts doc oa dan nc da D a 41 14029 SONE es RCo EA t ci it iza into cea ar al al le rai ae ai ala luato ed ta a lat ta 41 MI 3295 Step Contact Voltage Measuring System Preface 1 Preface Congratulations on your purchase of the measuring system from METREL The Step Contact Voltage Measuring System consists of Station MI 3295S and Meter MI 3295M and is intended for the following tests and measurements UU UL O Step voltage Contact voltage Earth resistance Specific earth resistance The instrument is equipped with all the necessary accessory for comfortable testing The PCSW HVlink PRO enables downloading of results storing of results and making test reports Some measuring system highlights E Q E DOoOvo DL Graphic LCD displays on Meter and Station Autonomous Step Contact Voltage Meter s Over 1000 memory locations in data flash memory for storing test results amp parameters USB and RS232 ports on Meter for communication with PC Synchronization between Meter and Station Large test current of up to 50 A Stable and accurate results due to a DSP measuring system Fully compatible with new METREL HVLink PRO PC
39. turns to Settings main menu 5 4 3 Initial settings The instrument settings and measurement eS ae and Function parameters and limits can be set to their Parameters will be initial factory settings in this menu P E sta pE YES Figure 5 6 Initial settings screen Cursor LEFT RIGHT Selects Yes or No TEST Restores initial settings if Yes is selected ESC Exits back to Settings main menu without changes Initial settings are Instrument setting Default value Default value English 17 MI 3295 Step Contact Voltage Measuring System MI 3295M Meter operation Parameters limit value Contact Voltage Iser 10 A lFAuLT 1 kA Rinput 1 MO Uumr 50 V Step Voltage Iser 10 A lFAuLT 1 KA Rinput 1 MQ Ur 50 V 5 4 4 Date and time Date and time can be set in this menu SET DATE HE iz e a Fii IET 41 7808 Figure 5 7 Setting date and time Keys 5 4 5 Synchronization selecting this option will allow to upload different data from the Station to the Meter and vice versa Options are a Synchronization of date time and STEF CONTHCT VOLT Current EARTH RESULTS a Uploading of test current results for Step Contact voltage calculation a Uploading of earth resistance results Figure 5 8 Synchronization menu Keys synchronized data TIME CURRENT Station s time and date will be uploaded to the Meter Value of generator current will be uploaded to the Meter if cur
40. y cells while power supply adapter is connected otherwise they may explode a Disconnect all test leads remove the power supply cable and switch off the instrument before removing battery compartment cover a The weight of each test probe is 25 kg This weight may be harmful if the probes are not lifted and carried appropriately Station MI 3295S a During instrument operation ventilation holes on casing should always stay open to ensure sufficient air flow for cooling a Disconnect all test leads switch off the instrument and remove the mains cord before changing the fuse a The weight of the MI 3295S is 29 5 kg This weight may be harmful if the instrument is not lifted and carried appropriately It is recommended that the instrument is transported by 2 persons 2 2 Battery and charging of MI 3295M The instrument MI 3295M uses six AA size alkaline or rechargeable Ni Cd or Ni MH battery cells Nominal operating time is declared for cells with nominal capacity of 2100 mAh Battery condition is always displayed in the lower right display part In case the battery is too weak the instrument indicates this as shown in figure 2 1 This indication appears for a few seconds and then the instrument turns itself off MI 3295 Step Contact Voltage Measuring System Safety and operational considerations TOO LOW Bl Figure 2 1 Discharged battery indication The battery is charged whenever the power supply adapter is connected to the
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