Transcription

NIM 1000Net Impedance MeterUSER GUIDEIssue:Article number:04 (06/2016) - EN829411

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Consultation with MeggerConsultation with MeggerThe present system manual has been designed as an operating guide and forreference. It is meant to answer your questions and solve your problems in as fast andeasy a way as possible. Please start with referring to this manual should any troubleoccur.In doing so, make use of the table of contents and read the relevant paragraph withgreat attention. Furthermore, check all terminals and connections of the instrumentsinvolved.Should any question remain unanswered or should you need the help of an authorizedservice station, please contact:Megger LimitedSeba DynatronicMess- und Ortungstechnik GmbHArchcliffe RoadKent CT17 9ENT: 44 1304 502100F: 44 1304 207342E: [email protected] 6D - 96148 BaunachT: 49 9544 68 – 0F: 49 9544 22 73E: [email protected] KMTKabelmesstechnik GmbHMegger USARöderaue 41D - 01471 Radeburg / DresdenValley Forge Corporate Centre2621 Van Buren AvenueNorristown, PA 19403 USAT: 1 610 676 8500F: 1 610 676 8610T: 49 35208 84 – 0F: 49 35208 84 249E: [email protected] MeggerAll rights reserved. No part of this handbook may be copied by photographic or other means unless Meggerhave before-hand declared their consent in writing. The content of this handbook is subject to change withoutnotice. Megger cannot be made liable for technical or printing errors or shortcomings of this handbook.Megger also disclaims all responsibility for damage resulting directly or indirectly from the delivery, supply, oruse of this matter.3

Terms of WarrantyTerms of WarrantyMegger accept responsibility for a claim under warranty brought forward by a customerfor a product sold by Megger under the terms stated below.Megger warrant that at the time of delivery Megger products are free from manufacturingor material defects which might considerably reduce their value or usability. Thiswarranty does not apply to faults in the software supplied. During the period of warranty,Megger agree to repair faulty parts or replace them with new parts or parts as new (withthe same usability and life as new parts) according to their choice.This warranty does not cover wear parts, lamps, fuses, batteries and accumulators.Megger reject all further claims under warranty, in particular those from consequentialdamage. Each component and product replaced in accordance with this warrantybecomes the property of Megger.All warranty claims versus Megger are hereby limited to a period of 12 months from thedate of delivery. Each component supplied by Megger within the context of warranty willalso be covered by this warranty for the remaining period of time but for 90 days atleast.Each measure to remedy a claim under warranty shall exclusively be carried out byMegger or an authorized service station.This warranty does not apply to any fault or damage caused by exposing a product toconditions not in accordance with this specification, by storing, transporting, or using itimproperly, or having it serviced or installed by a workshop not authorized by Megger.All responsibility is disclaimed for damage due to wear, will of God, or connection toforeign components.For damage resulting from a violation of their duty to repair or re-supply items, Meggercan be made liable only in case of severe negligence or intention. Any liability for slightnegligence is disclaimed.Since some states do not allow the exclusion or limitation of an implied warranty or ofconsequential damage, the limitations of liability described above perhaps may notapply to you.4

ContentsContentsConsultation with Megger . 3Terms of Warranty . 4Contents . 51Basic Notes . 72Technical Description . 92.1System Description . 92.2Technical Data .112.3Connections, Controls and Display .123Electrical connection .134Operation .164.1System Settings 24.2.2.3Performing Measurements .19Network Impedance Measurement .20Prepare Measurement.20Performing the Measurement .22Analysing Measurement Results .23Measuring in Fault Mode .25Preparing Measurement .25Performing the Measurement .26Identifying and Locating Faults .274.3Exporting the Measured Data .285Maintenance and care .29Annex 1: Measuring Accuracy .30Annex 2: Measuring Range.325

Basic Notes1Basic NotesSafety precautions This handbook contains basic instructions for the initial use and operation of the NIM1000. For this reason, it is important to ensure that the manual is always available toauthorised and trained personnel. Operating personnel should read the manualthoroughly. The manufacturer will not be held liable for any injury or damage topersonnel or property through failure to observe the safety precautions contained in thishandbook.The specific standards and regulations in each country must also be observed.Labelling of safety Important instructions concerning personnel, operational and technical safety areinstructions marked in the text as follows:SymbolDescriptionIndicates a potential danger of an electric shock that may result in fatal orserious injury.WARNINGIndicates a potential danger that may lead to slight or moderate injury.CAUTIONThe notes contain important information and useful tips for using thesystem. Failure to observe them can render the measurement resultsuseless.Working with products It is important to observe the general electrical regulations of the country in which thefrom Megger device will be installed and operated, as well as the current national accident preventionregulations and internal company directives (work, operating and safety regulations).Use genuine accessories to ensure system safety and reliable operation. The use ofother parts is not permitted and invalidates the warranty.Operating staff This system and its peripheral equipment may only be operated by trained or instructedpersonnel. Anyone else must be kept away.The system may only be installed by an authorised electrician. DIN VDE 0104 (EN50191), DIN VDE 0105 (EN 50110) and the German accident prevention regulations(UVV) define an electrician as someone whose knowledge, experience and familiaritywith the applicable regulations enables him to recognise potential hazards.Declaration of The product meets the following security requirements of the European CouncilConformity (CE) Directives: EMC Directive (2004/108/EC) Low Voltage Directive (2006/95/EC) RoHS Directive (2011/65/EU)7

Basic NotesRadiated emission The device is intended for operation in the industrial segment in accordance with EN55011. When used at home it could cause interference with other equipment (such asthe radio or television).The interference level from the line complies with the limit curve B (living area), theradiation level complies with the limit curve A (industrial area). Once the living area issufficiently far away from the planned area of operation (industrial area), equipmentthere will not be impaired.Use only as intended The operating safety is only guaranteed if the delivered system is used as intended.Incorrect use may result in danger to the operator, to the system and the connectedequipment.The thresholds listed in the technical data may not be exceeded under anycircumstances. Condensation during the operation of Megger products may result indanger to persons and devices through voltage arc-over. Prevent condensation beforeand during the measuring mode by cooling the measuring systems sufficiently. Theoperation of Megger products in direct contact with water, aggressive substances andinflammatory gases and vapours is prohibited.The NIM 1000 is built to be robust and can withstand the stresses it can expect to besubjected to in demanding everyday use. Nevertheless, it is a precision measuringdevice which needs to be treated with the appropriate care. This applies in particular tothe connection cable and the clamps, which play an important role in ensuring thedevice remains safe while the results of measurements remain precise.Procedure in the event The system may only be operated whilst it is in perfect working condition. In the event ofthat the device damage, irregularities or malfunctions that cannot be resolved with the assistance of themalfunctions operating instructions, the system must be shut down immediately and labelledaccordingly. In such an event, the relevant management must be informed. Pleasecontact Megger Service immediately to eliminate the malfunction. The system may onlybe started up again once the malfunction has been eliminated.8

Technical Description2Technical Description2.1System DescriptionIntended use The NIM 1000 serves to measure network impedance in low voltage grids. In thisprocess, the conductor connections are tested for their current carrying capacity whilesubjected to typical operating loads and potential flaws are indicated.With the help of the following range of preventative applications, a consistently goodsupply quality can be guaranteed, outages prevented and adequate network ratingensured: Preventative inspection and uncovering of faults (e.g. neutral conductor fault) Determination of the maximum connected / feed-in power Monitoring for secure shut-down (rating of fuses) Approval of new / modified network sectionsFault detection in low voltage grids is another area of application of the device. Forexample, the NIM 1000 can be used to trigger a load-dependent fault which can then belocated either with the help of a simultaneously connected measuring device or bymeans of multiple measurements at various connection points.Function The device is linked to the low voltage grid to be tested by means of the availableconnection cables (four-conductor measurement with Kelvin clips) and also receives itssupply voltage over these wires.In preparation for a measurement, either a defined measurement period or a targetnumber of measurements can be specified.To determine the network impedance, the adjustable load current is generated for ashort period by means of a semi-conductor circuit-breaker with the appropriate loadresistor. The current and voltage curves are recorded immediately before and whileapplying the load by means of A/D converters and then analysed by calculation. Theresult is shown on the display.When taking measurements on more than one phase, there is automatic switchingbetween the phases.9

Technical DescriptionFeatures The NIM 1000 combines the following features in one device: Compact and sturdy design for portable use in the field Easy and convenient operation via rotary encoder Single and three phase measurement High test current of up to 1000 A Network impedance measurement (resistance and reactance) up to the10th harmonic Automatic detection of rotary field Logging (export via USB interface) Wide range input for the voltage supplyScope of delivery The scope of delivery of the system includes the following:Quantity ComponentDescriptionItem number1Basic device1283121474High performanceKelvin clampPKC-1900093192Connection leadbrown900093202Connection leadblack900093212Connection leadgrey900093222Connection leadblue900093231NIM 1000-A socketadapter1283116271USB flash drive89002092810Spare fuses1ManualT 25A H 440V (6.3 mm x 32 mm) 9000474582941Check contents Check the contents of the package for completeness and visible damage right afterreceipt. In the case of visible damage, the device must under no circumstances be takeninto operation. If something is missing or damaged, please contact your local salesrepresentative.Optional accessories If the following optional accessories do not form part of the scope of delivery, these canbe ordered from sales:AccessoryDescriptionKelvin clip withconnection cableSmaller clip ideally suited for use when space 138315892is restricted.10Item number

Technical Description2.2Technical DataThe NIM 1000 is defined by the following technical parameters:ParameterValueTest current Range80 A 1000 A (adjustable) Maximum current as a peak value(Imax depends on the networkimpedance and the temperature andis, under certain circumstances,significantly lower than the indicatedvalues) 1000 A at 400 V 600 A at 230 V 300 A at 115 VInput voltage(supply voltage at the same time)100 V . 480 V, 50/60 Hz(at test terminals)100 V 230 V, 50/60 Hz(at Schuko socket)Operating uncertainty B (in accordancewith IEC 61557-3)Up to 3% 1 mΩ (see also Annex 1)Measuring range10 mΩ 5 Ω (230 V / 400 V)10 mΩ 2,5 Ω (115 V)(See also Annex 2)Resolution1 mΩMeasurement category300V CAT IV or600V CAT IV (when using the PKC-1 highperformance connection clamps)Safety functionsTemperature monitoringDisplayTransflective sunlight readable 5.7" colourdisplay with a resolution of 640 x 480 pixelsMemoryAt least 1000 records of test dataInterfacesUSB 2.0Operating temperature-20 C to 55 COperating humidityMax. relative humidity 93% at 30 CStorage temperature-30 C to 70 CWeight10 kgDimensions410 x 175 x 335 mmProtection class (in accordance withIEC 61140 (DIN VDE 0140-1))IIIngress protection rating (in accordance IP 50 (open)with IEC 60529 (DIN VDE 0470-1))IP 54 (closed)11

Technical Description2.3Connections, Controls and DisplayThe NIM 1000 has the following connection, display and control elements:Element DescriptionDisplayRotary encoderUSB portConnection cablesTrigger output12

Electrical connection3Electrical connectionWork on live equipmentThe work can only be carried out safely while guaranteeing the protectionof the health of all those involved in the work by employing suitableworking procedures and using suitable protective equipment. For thatWARNINGreason, the electrical connection of the device must absolutely conform tothe nationally applicable regulations for work on live equipment!Connection sequenceWhen connecting the device, the two blue connection cables should beconnected to the neutral conductor of the low voltage cable first. Not untilWARNING after that can the live phase conductors be connected. The conductors aredisconnected in reverse order: first disconnect the phase conductors, thenthe neutral conductor.Connection diagram The following figure shows the simplified connection diagram for the NIM 1000:The fused measurement cables are colour-coded (brown L1,black L2, grey L3, blue N).Only a measurement cable with a matching colourcode may ever beCAUTION connected to one and the same Kelvin clip!13

Electrical connectionNotes When making electrical connections, the following points should be observed: When connected with the supplied PKC-1 high performance connection clamps,the NIM 1000 is approved for measurements on low voltage installations in themeasurement category 600V CAT IV in accordance with IEC 61010-1. The input voltage live on the measurement cables serves simultaneously assupply voltage and must remain within the range of 100 V and 480 V. The NIM 1000 must be connected to the neutral conductor and at least onephase. If the neutral conductor is not accessible, the blue connection cable mustbe connected to a free phase conductor. The connection should be made based on the principle of four-conductormeasurement. So two measurement cables (current and voltage) must beconnected to each conductor intended to be measured using a Kelvin clip.Specific connection- Using the NIM 1000, measurements can be carried out in both single-conductor modeconfigurations (just L1–N) as well as in multi-conductor mode (all possible conductor combinations).Measurements are only carried out on phases which are live with a suitable inputvoltage. Accordingly, phases which have not been connected will not be taken intoaccount in multiple-conductor mode.So, for special applications or for time-saving reasons, the conductor combinations to bemeasured can be purposefully limited in the multiple-conductor mode by using a specificconnection configuration. The following table shows some examples of this:RequiredmeasurementsPhases to beconnectedMeasured conductor pairs(instead of the 6 possiblecombinations)L2–NN (blue)L2 (black)L2–NL1–L2N (blue)L1 (brown)L2 (black)L1–NL2–NL1–L2L2–L3L2–NN (blue)L2 (black)L3 (grey)L2–NL3–NL2–L3Connection to IT Measurements can also be carried out on IT networks using the NIM 1000.networksGiven the lack of a neutral conductor, in measurements on networks of this kind it isrecommended that the blue test lead be connected to a free phase.If, however, all phases are assigned test leads in multi-conductor mode, it is advisablethat the blue test lead be connected to the station earth or, in the case of an emergency,even an earthing spike, in order to avoid faults in the voltage- and frequency detection(otherwise the measurement will not start).14

Electrical connectionConnection to mains Using the included NIM 1000-A adapter, the NIM 1000 can be quickly and safelysocket connected to a mains socket for the purposes of measurement or the export ofmeasurement data. The plug is designed as a Schuko plug (CEE 7/4) but it can also beconnected to sockets of different designs without problem using the appropriateaccessories.The connection between the NIM 1000 and the adapter should be established as followswith the help of the blue and the brown connection cables:15

Operation4OperationPower on As soon as one of the three connection cables has been connected to a low voltagephase with sufficient supply voltage (100 V . 480 V), the NIM 1000 automatically turnson.After the short switching on process, the system waits for confirmation from the user thatthe electrical connection has been finished.The corresponding dialogue window can be shut by a quick push of the rotaryencoder, following which the three phase voltages are measured (audible phaserelay switching).System status After switching on, the following information on the current status of the system is shownon the left side of the display:Connected phases which are takeninto account in a measurement in3-conductor mode.Set measuring currentNetwork voltage and frequencycurrently measuredSelected measuring mode (number ofmeasurements or measurementduration) and selected operatingmode16

OperationIf it has been possible to detect the rotary field’s direction of rotation, this will beindicated by the colour in which the phase designations are displayed:Counter-clockwise rotary fieldClockwise rotary fieldIf, however, it is not possible to determine the direction of rotation say, for example,because less than three phases have been connected or because one phase hasaccidentally been connected multiple times, the phases are displayed in a black font.Operating concept Navigation within the menus is effected almost entirely from the circular selection menu:Currently selectedmenu itemDescription of thecurrently selectedmenu itemOperating the system with the rotary encoderSystemis as follows:Select the menu itemIncrease or decrease the value of a variable parameter Select an option from a selection list Call up the selected menu itemConfirm the setting or the selection madeEach menu (with the exception of the main menu) has a menu itemcan return to the next higher menu level.17with which one

Operation4.1System SettingsSelecting the menu itemtakes you directly to the system menu, where the followingfunctions and submenus are available:MenuitemDescriptionSubmenu with detailed system informationInformation on the current versions of the various softwarecomponentsHardware information (e.g. serial number of the system)System settingsSetting the interface language.Select the desired language by turning the rotary encoder and activateby pressing it. The language selection is immediately active.In this submenu, the brightness and layout of the display can beadjusted and the background lighting can be switched on or off.Setting the date and time.The value of each segment that has been marked for selection can beadjusted by turning the rotary encoder. Pressing causes the mark tomove the next segment.Once the input has been concluded, the changes can either beaccepted with OK or rejected by selecting Cancel.When this function is used, a search in respect of firmware and language filesis conducted in the directory nig/updates/ on the inserted USB flash drive.The files found are then listed and, using the rotary encoder, these can beselected and imported. A distinction is made between the following file types:application-x.xx.imgUpdating solely an application to version x.xxnig-xxx.tarImporting the language xxxnig-Languages.tarImporting all the languages contained in thelanguage fileAn also possible update of the real-time software of the measuringhardware needs not be initiated via this menu item. Instead of this, itsuffices to insert the USB flash drive with the update files into the USBport and confirm the following query.18

Operation4.2Performing MeasurementsSelecting the operating By selecting themenu item in the main menu you will reach a sub menu in whichmode you may select your desired operating mode. In principle, measurements may be carriedout either in normal network impedance measuring mode or in fault detection mode.Normal network impedance measuring takes place with a constant measuring currentand over a freely-adjustable duration or number of measurements. Only in this modecan the software carry out a load calculation (see page 7) on the basis of the measurednetwork impedance. However, the suitability of this mode to detect faults is limited, assome faults subside temporarily with higher current flows (e.g. due to fusing or dryingout). Depending on the level of the measuring current selected, this could alreadyhappen during calibration and so the fault would remain undetected through themeasurement.That is why fault mode has been integrated. In this mode, the load current is graduallyincreased over the course of 8 measurements up to the preset value. All 8 recordedcurves are displayed together in one diagram, whereby the relevant changes can beeasily identified.Further sub-division into single and multiple conductor mode gives the followingoperating modes:MenuDescriptionitemNetwork impedance measurement on one conductorThe impedance is only measured on the phase which is connected via the brownconnection cables (L1).This time-saving single-conductor mode is particularly suitable if the results ofone phase suffice for the intended purpose of the measurement or if only singlephase measuring is possible anyway (e.g. at sockets).Network impedance measurement on up to 6 conductor combinationsIn this mode, all possible conductor combinations (see page 14) are measuredone after the other depending on the connection situation.Fault mode on one conductorThis serves to trigger a known load-dependent fault on the phase connected tothe brown connection cables (L1).This mode is recommended if the conspicuous phase has already beenidentified.Fault mode on up to three conductorsIn this mode the 8 measurements are carried out on all connected phases(against the neutral conductor).So conclusions on the characteristic of the fault can be drawn from loaddependent impedance changes as well as from the comparison of the phaseswith one another.19

Operation4.2.1Network Impedance Measurement4.2.1.1 Prepare MeasurementSetting the By selecting themenu item in the main menu you will reach a sub menu in whichmeasurement you may select the following measurement parameters in preparation for a networkparameters impedance measurement.MenuitemDescriptionMaximum measuring current (80 . 1000 A)Because the accuracy of the measurement increases with increasingmeasuring current, as high as possible a measuring current but also one whichis appropriate to the capacity of the network should be selected.If the NIM 1000 is connected to a mains socket (with fusing of up to16 A), the 80 A setting which has been particularly dimensioned forthis type of application should be selected!Total measurement duration (0 20 days) and interval of the individualmeasurements.Over the whole measurement duration, one measurement per involved phaseis taken at the set interval.After the menu item is selected, the two values are to be defined one afteranother. The options for setting the interval depend on the previously set totalmeasurement time.The number of measurements can also be defined as an alternative tomeasurement duration (see below). The respective last adopted settingapplies.Number of measurements (1 255)The set number of measurements is carried out in quick succession and whileconstantly switching between the phases involved.The measurement duration can also be defined as an alternative to thenumber of measurements (see above). The respective last adopted settingapplies.Delay time (0 30 seconds)The start of the measurement can be delayed by the time set here.Resetting calibration valuesIf the time of calibration was quite a while ago (e.g. after a measurement whichlasted a while or in the case of temporary failure of a phase), it could be usefulto reset the calibration values.Value to be calculated using a load calculation (see information on next pagetoo)VDIPVoltage dip at given connection powerPMAXMax. connection power at given voltage dipOffLoad calculation deactivated20

OperationExplanations When it comes to the load calculation, the NIM 1000 utilises the following physicalconcerning the load correlation between the measurements for short-circuit power PK, the maximum ratedcalculation output PMAX and the anticipated voltage dip VDIP:Z / PK(1 – VDIP) UUPMAXMeasurementAnalysis (load calculation)2𝑉𝐷𝐷𝐷 𝑉𝐷𝐷𝐷 𝑃𝑀𝑀𝑀 0𝑃𝑘Now, depending on the application scenario, only one of the two unknown variablesneed be given in order to calculate the other:Application scenarioProcedureA large consumer with a known load (PMAX) should beconnected to the measurement point and theanticipated voltage dip (in %) calculated.Call up themenu item andselect the option VDIP. Thenenter the load of the appliance.The aim is to calculate the maximum load which can beconnected to the measurement point without anyvoltage dip defined by existing guidelines beingexceeded.Call up themenu item andselect the option PMAX. Thenenter the maximum permissiblevoltage dip.This function can also be used to calculate themaximum feed-in load (e.g. of a PVinstallation). Accordingly, in this case it is themaximum permissible mains voltage increaseinstead of the voltage dip which must bespecified.21

Operation4.2.1.2 Performing the MeasurementStart measurement Once all the settings have been carried out and checked, the measurement can bestarted with the menu item.If this is the first measurement after switching on the device or if the calibration valueswere reset before the measurement (see previous page), calibration will be carried outright after the start in order to set the preset maximum measuring current. Acorresponding notice will appear on the display.Performing the Depending on the settings, the individual measurements will take place either in quickmeasurement succession (depending on the measuring current 2 to 10 seconds) or at 15 minuteintervals, switching between the involved phases.The following measured values are shown on the display and continually updated duringthe running measuring process as standard.Frequency-based resistance curvered current measurementgreen averageFrequency-based reactance curvered current measurementgreen averageActual measuringcurrentShort circuitcurrent andpowerNumber of measurements alreadycarried out or already expiredmeasurement durationCurrent resistance and reactancemeasured values at mains frequency andat their 3rd and 9th harmonicUsing themenu item during and after the measurement, the diagram types may beswitched between as follows:R/X Z /PhiU/IImpedance resistance and reactanceImpedance amount and phase shift angleCurrent and voltage curve of the period in which the measurement took placeEnding

Hagenuk KMT. Kabelmesstechnik GmbH. Megger USA. Röderaue 41 D - 01471 Radeburg / Dresden . . Megger agree to repair faulty parts or replace them with new parts or parts as new (with the same usability and life as new parts) according to their choice. . Use genuine accessories t