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GMC-I Messtechnik GmbH

11

5.5

Help Function

The following information can be displayed for each switch 
position and basic function 

after it has been selected with the rotary 

selector switch

:

• Wiring  diagram
• Measuring range
• Nominal range of use and Measuring Uncertainty
• Nominal  value

Ð

Press the 

HELP

 key in order to query online help:

Ð

If several pages of help are available for the respective 
measuring function, the 

HELP

 key must be pressed repeatedly.

Ð

Press the 

ESC

 key in order to exit online help.

5.6

Setting Parameters or Limit Values using RCD Measurement as an Example

1 Access the submenu for setting the desired parameter.

2 Select the parameter with the 



or



scroll key.

3 Go to the settings menu for the selected parameter with the 



scroll key.

4 Adjust the value with the 



or



scroll key.

5 Acknowledge the setting value with the 

 key. This value is transferred to 

the settings menu.

6 The setting value is not permanently accepted for the 

respective measurement until 

3

 is pressed, after which the display is 

returned to the main menu. You can return to the main menu by pressing 
ESC instead of 

3

 without accepting the newly selected value.

Parameter Blocking

The individual selected parameters are subjected to a plausibility 
test before they are accepted by the measuring window. 
If the selected parameter does not make sense 
in combination with the other parameters that 
have been preset, it is not accepted and an 
error window appears.
The parameter previously set is retained in the 
memory. 
Remedy: Select another parameter.

1

2

2

3

4

4

5

6

2

4

3

5

6

Summary of Contents for PROFITEST MBASE MTECH

Page 1: ...Operating Instructions PROFITEST MBASE MTECH Test Instruments for IEC 60364 6 DIN VDE 0100 3 349 470 03 9 4 12 ...

Page 2: ...ment ESC Return to submenu 13 3 1 Softkeys Control Panel Test Instrument and Adapter 16 17 15 Current Clamp and Probe Connections 14 Fixed Function Keys 2 18 19 20 21 Interfaces and Charger Connection 12 RS 232 2 Parameter selection Specify limit value Entry functions Memory functions LEDs connection symbols section 18 1 9 10 Refer to section 2 1 on page 5 regarding usage of the test probes 15 16 ...

Page 3: ...ge 7 Brightness contrast Date time Language D GB P Profile ETC PC doc Default settings Test LED LCD Acoustic signal Rotary switch balanc batt level I N Page 15 UI N Contact voltage ta Tripping time RE Earth resistance U UN Line voltage Nominal line voltage f fN Line frequency Nominal line frequency IF Page 17 UI N Contact voltage I Residual current RE Earth resistance U UN Line voltage Nominal lin...

Page 4: ...f RCD Tripping 24 8 1 1 Measurement with Positive Half Waves only PROFITEST MTECH 24 8 2 Evaluation of Measured Values 25 9 Measuring Line Impedance ZL N function 25 10 Earthing Resistance Measurement function RE 27 10 1 Measuring with Probe 28 10 2 Measuring Without Probe 29 10 3 Measuring Earth Electrode Potential function UE 30 10 4 Selective Earth Resistance Measurement with Accessory Current ...

Page 5: ... m cable as optional acces sory PRO RLO II Z501P KS24 cable set as optional accessory GTZ3201000R0001 Measurements per DIN EN 61010 031 may only be performed in environments in accordance with measuring categories III and IV with the safety cap attached to the test probe at the end of the measurement cable In order to establish contact inside 4 mm jacks the safety caps have to be removed by prying...

Page 6: ...ries Attention Before opening the battery compartment disconnect the instrument from the measuring circuit mains at all poles Note We recommend rechargeable NiMH batteries See also section 19 2 on page 56 concerning charging and the battery charger Always replace batteries in complete sets Dispose of rechargeable batteries in an environmentally sound fashion towards the end of their useful life ch...

Page 7: ...d Contrast Settings Time On Time and Default Settings Menu Selection for Operating Parameters LED Tests LCD and Acoustic Signal Tests On time Test Instrument Cell test Inverse cell test Hide all pixels Show all pixels Acoustic signal test Return to main menu MAINS LED test green MAINS LED test red UL RL LED test red RCD FI LED test red Return to main menu Increase brightness Decrease brightness In...

Page 8: ...e settings minutes Increase seconds Return to main menu Increase brightness Decrease brightness Increase contrast Decrease contrast Set time Profiles for distributor Default settings structures Language of online instructions 3a 3b 3c 3d 3e Set date LED and LCD test menu Rotary switch balancing menu Brightness contrast menu Software revision level calibration date Display date time Display automat...

Page 9: ...is generated as a warning when the Readjust softkey is pressed 6 Return to point 2 and continue Repeat this procedure until all rotary switch functions have been tested and if necessary readjusted Ð Press ESC in order to return to the main menu Submenu Battery Level Query If battery voltage falls short of or equals 8 0 V the UL RL LED lights up red accompanied by an acoustic warning signal Note Me...

Page 10: ...etermined on time has expired see section 4 3 On time is reset to its original value as defined in the setup menu as soon as any key or the rotary selector switch is activated The instrument remains on for approximately 75 seconds in addition to the preset on time for measurements with rising residual current in systems with selective RCDs The instrument always shuts itself off automatically 5 3 M...

Page 11: ...key 3 Go to the settings menu for the selected parameter with the scroll key 4 Adjust the value with the or scroll key 5 Acknowledge the setting value with the key This value is transferred to the settings menu 6 The setting value is not permanently accepted for the respective measurement until 3 is pressed after which the display is returned to the main menu You can return to the main menu by pre...

Page 12: ... using the ETC program 5 8 New Two Pole Measurement with Rapid or Semiautomatic Polarity Reversal Rapid semiautomatic two pole measurement is available for the following tests Voltage measurement U Loop impedance measurement ZLP E Insulation resistance measurement RISO Rapid polarity reversal at the test plug The polarity parameter is set to AUTO Quick convenient switching through all of the polar...

Page 13: ...UL PE as well as N and PE UN PE for country specific plug insert e g SCHUKO Repeatedly press the sofkey shown at the left in order to switch back and forth between the country specific plug insert e g SCHUKO and the 2 pole adapter The selected connection type is displayed inverse white on black 6 1 2 Voltage between L PE N PE and L L for connection of 2 pole adapter Repeatedly press the sofkey sho...

Page 14: ...tches are installed to the phase conductors 7 Testing RCDs The testing of residual current devices RCDs includes Visual inspection Testing Measurement The test instrument is used for testing and measurement Measuring Method The following must be substantiated by generating a fault current downstream from the RCD That the RCD is tripped no later than upon reaching its nominal fault current value Th...

Page 15: ...remagnetization The 2 pole adapter is only provided for AC measure ments Suppression of RCD tripping by means of pre magnetization with DC current is only possible via a country specific plug insert e g SCHUKO or a 3 pole adapter Measurement With or Without Probe Measurements can be performed with or without a probe Measurements with probe require that both probe and reference earth are of like po...

Page 16: ...g of the RCD due to Leakage Current in the Measuring Circuit Measurement of contact voltage with 30 nominal residual current does not normally trip an RCCB However the trip limit may be exceeded as a result of leakage current in the measuring circuit for example due to interconnected power consumers with EMC circuits such as frequency converters and PCs 2 Tripping Test after the Measurement of Con...

Page 17: ... reaches nominal residual current I N the RCD FI LED lights up red Attention If biasing current is present within the system during measurement it is superimposed onto the residual current which is generated by the instrument and influences measured values for contact voltage and tripping current See also section 7 1 Evaluation According to DIN VDE 0100 part 600 rising residual current must howeve...

Page 18: ...tive or Negative Half Wave Set Parameters Testing with and without Biasing Current Non Trip Test Testing with Biasing Current If RCD is tripped to early during the non trip test with 50 I N for 2 seconds i e prior to actual tripping the popup window shown at the right appears Note The following limitations apply when selecting X times tripping current relative to nominal current 300 mA 1 x I N 2 x...

Page 19: ...med immediately by pressing key I N 7 3 2 PRCDs with Non Linear Type PRCD K Elements The PRCD K is a portable differential current system with elec tronic residual current evaluation which being conceived as an intermediate cable device switches at all poles L N PE The PRCD K also includes undervoltage tripping and protective con ductor monitoring As the PRCD K features undervoltage tripping it mu...

Page 20: ...ual current flows from L to PE tripping current is cut in half i e the RCCB must be tripped at 50 nominal residual current I N Whether or not PRCDs and selective RCDs are of like design can be tested by measuring contact voltage UI N If a contact voltage UI N of greater than 70 V is measured at the PRCD of an otherwise error free system the PRCD more than likely contains a non linear element PRCD ...

Page 21: ...ping test with the positive half wave at 0 and the negative half wave at 180 The longer of the two tripping times is decisive regard ing the condition of the tested RCCB Set Parameters Positive or Negative Half Wave Set Parameters 5 Times Nominal Current Note The following limitations apply when selecting X times tripping current relative to nominal current 300 mA 1 x I N 2 x I N 500 mA 1 x I N St...

Page 22: ...her with minimal loop resistance result in a very small voltage value Measuring resolution is 0 1 V and the display value is thus rounded down to 0 0 V 7 5 Testing Residual Current Circuit Breakers RCDs in IT Systems with High Wiring Capacitance e g in Norway The system type TN TT or IT can be adjusted for UI N I N ta RCD tests and for earth resistance measurements RE For measurements in IT system...

Page 23: ...rrent IK based on measured loop impedance ZL PE and line voltage Short circuit current calculation is made with reference to nominal line voltage for line voltages which lie within the nominal ranges for 120 V 230 V and 400 V systems If line voltage does not lie within these nominal ranges the instrument calculates short circuit current IK based upon prevailing line voltage and measured loop resis...

Page 24: ...g meanings IK Ia The measured value displayed for ZL PE is used with out any correction to calculate IK IK Ia The measured value displayed for ZL PE is corrected by an amount equal to the test instrument s measuring uncertainty in order to calculate IK IK 2 3 Z In order to calculate IK the measured value displayed for ZL PE is corrected by an amount corresponding to all possible deviations these a...

Page 25: ...e cannot be determined The test person is requested to evaluate the measured values himself and to acknowledge or reject them via softkeys Measurement passed Key 4 Measurement failed Key X The measured value cannot be stored until it has been evaluated by the test person 9 Measuring Line Impedance ZL N function Measuring Method internal line resistance measurement Supply impedance ZL N is measured...

Page 26: ...play of UL N UN fN If the measured voltage value lies within a range of 10 of the respective nominal line voltage of 120 V 230 V or 400 V the respectively corresponding nominal line voltage is displayed In the case of measured values outside of the 10 tolerance the actual measured value is displayed q ZOFFSET ON OFF Voltage Drop up to the Transfer Point or the Measuring Device Proceed as follows Ð...

Page 27: ...If dangerous contact voltages occur during measurement 50 V the measurement is interrupted and safety shut down occurs Probe resistance does not effect measurement results and may be as high as 50 k Attention The probe is part of the measuring circuit and may carry a current of up to 3 5 mA in accordance with VDE 0413 Characteristic Values of Earth Resistance Measurement Mains Powered Measuring ra...

Page 28: ...nnected components 2 pole adapter and probe Set parameters q Measuring range AUTO 10 k 4 mA 1 k 40 mA 100 0 4 A 10 0 65 A In systems with RCCBs resistance and or test current must be chosen such that they are below the tripping current I N q Connection type 2 pole adapter probe q Contact voltage UL 25 V 50 V 65 V freely adjustable voltage see section 5 7 q Transformer ratio without significance in...

Page 29: ...ral conductor N phase conductor resistance is half as great as supply impedance ZL N phase conductor neutral conductor Supply impedance can be measured as described in section 9 beginning on page 25 In accordance with DIN VDE 0100 the operational earth elec trode RB must lie within a range of 0 to 2 1 Measurement ZLN corresponds to Ri 2 RL 2 Measurement ZL PE corresponds to RLoop 3 Calculation RE1...

Page 30: ... potential the instrument first measures earth electrode loop resistance RELoop and immediately thereafter earthing resistance RE The instrument stores both values and then calculates earth electrode potential with the following equation The calculated value is displayed at the display panel Select the Measuring Function Connection Connected components 2 pole adapter and probe Set parameters q Mea...

Page 31: ...ction 5 7 Setting Parameters at the Current Clamp Sensor q Measuring range of current clamp sensor see table below Select the Measuring Range at the Current Clamp Sensor Important Instructions Regarding the Use of the Current Clamp Sensor Use only the METRAFLEX P300 or Z312A current clamp sensor for this measurement Read and adhere strictly to the operating instructions for the METRAFLEX P300 curr...

Page 32: ...ou to enter this new setting to the connected current clamp sensor as well i Prompt regarding currently selected transformer ratio at the tester REClamp Selective earth resistance measured with clamp REProbe Earth resistance measured with probe comparative value Note The following diagram appears if the 2 pole adapter is connected incorrectly ...

Page 33: ... unfavorable locations e g at joints or abutments with a damp cloth measuring approximately 270 x 270 mm Ð Place the 1081 Probe on top of the damp cloth and load the probe with a weight of 750 N 75 kg i e one person for floors or 250 N 25 kg for walls e g press against the wall with a hand isolated by a glove Ð Establish a conductive connection to the 1081 Probe and connect it to the probe connect...

Page 34: ...ement with rising test voltage is ended As soon as the specified maximum test voltage UN is reached and the measured value is stable or As soon as the specified test current is reached e g after spark over occurs at breakdown voltage Selected maximum test voltage UN or any available trigger or breakdown voltage is displayed for UISO The constant test voltage function or constant test voltage offer...

Page 35: ...d The MAINS NETZ LED lights up and the message Interference voltage present pops up All conductors L1 L2 L3 and N must be tested against PE Attention Do not touch the instrument s terminal contacts during insulation resistance measurements If nothing has been connected to the terminal contacts or if a resistive load component has been connected for measurement your body would be exposed to a curre...

Page 36: ...e floor probe 1081onto the point of measurement and load it with a minimum weight of 300 N 30 kg Ð Establish a conductive connection between the measuring electrode and the test probe and connect the measuring adapter 2 pole to an earth contact e g the earthing contact at a mains outlet or a central heating radiator Prerequisite safe earth connection Start Measurement The limit value for earth lea...

Page 37: ...further testing READY pictograph Note If a minimum power is not reached the test will not be started or will be aborted Special Case Start up of energy consumption meters which are connected between L and L or L and N can be tested with this function Connection L L 2 pole adapter Note If an earthing contact outlet is not available you can use the 2 pole adapter N must be contacted with the PE test...

Page 38: ...the difference between RLO and RLO is greater than 10 during automatic polarity reversal no offset value is accepted In all other cases the lower value is saved as offset value Maximum offset value is 9 99 Offset may result in neg ative resistance values Measuring ROFFSET The ROFFSET x xx message now appears in the footer at the dis play where x xx is a value between 0 00 and 9 99 This value is su...

Page 39: ...r to assure unambiguous measurement results causes of error must be located and eliminated In order to find the cause of the measuring error measure resistance in both directions of current flow The instrument s batteries are exposed to excessive stress during insulation resistance measurement For measurement with current flow in one direction only press and hold the START t key as long as necessa...

Page 40: ...perating instructions for the current clamp sensors as well as the safety precautions contained therein in particular with reference to the approved measuring category Select the Measuring Function Selecting a Measuring Range at the Current Sensor Clamp Set Parameters The transformation ratio parameter must be correspondingly set at the test instrument depending upon the respectively selected meas...

Page 41: ...ng Distributor Structures The following data transfer operations are possible Transfer a distributor structure from the PC to the test instrument Transfer a distributor structure including measured values from the test instrument to the PC The test instrument and the PC must be connected with a USB cable in order to trans fer distributor structures and data The following image appears at the displ...

Page 42: ... Menu Cursor LEFT Select an alphanumeric character Cursor RIGHT Select an alphanumeric character ENTER accept an individual character Acknowledge entry Cursor LEFT Cursor RIGHT Delete character Switching amongst different types of alphanumeric characters A Upper case letters a Lower case letters 0 Numbers Special characters Symbol Meaning Distributor A check mark measurement symbol next to a struc...

Page 43: ...ments measurement without saving data 16 3 2 Searching for Structural Elements Mark the structural element from which search is to be launched Those objects located beneath or next to this object are sear ched Jump to page 3 3 in the database menu After activation of text search and entry of the text you are looking for only 100 match is found no wild cards case sensitive the corresponding passage...

Page 44: ...e the parameters in the measuring view the changes will not be accepted for the structural element The measurement with the modified parameters can however be saved under the respective structural ele ment while the modified parameters are documented for each measurement Retrieving Saved Measured Values Ð Switch to the distributor structure by pressing the MEM key and to the requested electrical c...

Page 45: ...ctural element and works its way down into lower hierarchies The retrieved barcode is inverse displayed Ð This value is accepted by pressing the ENTER key Note An already selected object cannot be found Continued Search General Regardless of whether or not an object has been found searching can be continued with this key Object found search below the previously selected object No additional object...

Page 46: ...he measuring adapter 2 pole are attached to the test plug and secured with a threaded connector The control elements at the test plug are subjected to interference suppression filtering This may lead to a slightly delayed reaction compared to direct instrument control 7 Alligator Clip plug on 8 Test Probes The test probes comprise the second permanently attached and third plug on poles of the meas...

Page 47: ...ain that battery polarity corresponds the symbols when inserting the rechargeable batteries Attention Make sure that all of the rechargeble batteries are inserted with correct polarity If just one battery is inserted with reversed polarity it will not be recognized by the instrument and may result in battery leakage Two replacement fuses are located beneath the battery compartment lid Control Pane...

Page 48: ...Hz 10 rdg 30d 10 rdg 30d 5 rdg 3d 5 rdg 30d 4 rdg 30d 3 rdg 3d l l ZL PE ZL PE DC 0 25 0 99 1 00 9 99 18 rdg 30d 10 rdg 3d 6 rdg 50d 4 rdg 3d IK 0 A 999 A 1 00 kA 9 99 kA 10 0 kA 50 0 kA 1 A 10 A 100 A 120 108 132 V 230 196 253 V 400 340 440 V calculated value from ZL PE ZL PE 15 mA 0 5 9 99 0 01 only display range 10 0 99 9 100 999 0 1 1 15 mA 10 100 100 1000 UN 120 230 V fN 50 60 Hz 10 v M 10D 8...

Page 49: ...ng cycle 25 s pause approx 1000 measurements Overload Capacity RINS 1200 V continuous UL PE UL N 600 V continuous RCD RE RF 440 V continuous ZL PE ZL N 550 V limits the number of measurements and pause duration If overload occurs the instrument is switched off by means of a thermostatic switch RLO Electronic protection prevents switching on if interference voltage is present Protection with fine w...

Page 50: ...bles Weight Approx 2 3 kg with rechargeable batteries Protection Housing IP 40 test probe IP 40 per DIN VDE 0470 part 1 EN 60529 Extract from table on the meaning of IP codes Data Interface Type USB slave for PC connection Type RS 232 for barcode and RFID readers IP XY 1st char X Protection against foreign object entry IP XY 2nd char Y Protection against the penetration of water 0 not protected 0 ...

Page 51: ...ion Pictograph is displayed All except for U No connection detection is displayed All except for U Connection OK is displayed All except for U L and N reversed neutral conductor charged with phase voltage is displayed All except for U No mains connection is displayed All except for U Neutral conductor interrupted is displayed All except for U Protective conductor PE interrupted neutral conductor N...

Page 52: ...Ds is displayed UL RL FI RCD light up red X X U single phase measurement Potential difference 50 V between finger contact and PE earth contact Frequency f 50 Hz is displayed UL RL FI RCD light up red X X U single phase measurement If L is correctly contacted and PE is interrupted Frequency f 50 Hz Error Messages LCD X X All measurements with protective con ductor Potential difference 50 V between ...

Page 53: ...test instrument to cool down X X RISO RLO Interference voltage Remedy device under test must be disconnected from all sources of volt age X X All measurements with probe Interference voltage at the probe X X RISO RLO Overvoltage or overloading of the measurement voltage generator during measurement of RISO or RLO X X I N IF ZL N ZL PE ZST RST RE Meter start up No mains connection Remedy inspect ma...

Page 54: ...rrupted Result no measured value display RE I N IF Probe is not detected probe not connected Remedy inspect probe connection RE Clamp is not detected Clamp not detected or Current through clamp too small earth resistance too high or Transformer ratio set incorrectly Remedy inspect clamp connection check transformer ratio check replace the batteries in the METRAFLEX P300 RE If you have changed the ...

Page 55: ... not suited for this interface All Operation with a barcode scanner Barcode not recognized incorrect syntax All Operation with a barcode scanner Data cannot be entered at this point within the structure Remedy Observe profile for preselected PC software see SETUP menu All Storage of measured values is not possible at this point in the structure Remedy Check whether you have set the appropriate pro...

Page 56: ...ns included with the charger regarding the meanings of LED displays during the charging process Ð Do not disconnect the charger from the test instrument until the green LED charged ready lights up 19 3 Fuses If a fuse has blown due to overload a corresponding error message appears at the display panel The instrument s voltage measuring ranges are nevertheless still functional Replacing Fuses Atten...

Page 57: ...50 k 4 08 k 0 50 0 43 50 0 45 4 5 00 k 4 54 k 0 60 0 51 60 0 54 5 6 00 k 5 45 k 0 70 0 60 70 0 63 6 7 00 k 6 36 k 0 80 0 70 80 0 72 7 8 00 k 7 27 k 0 90 0 79 90 0 81 7 9 00 k 8 17 k 1 00 0 88 100 90 8 9 99 k 9 08 k 1 50 1 40 150 133 2 00 1 87 200 179 2 50 2 35 250 224 3 00 2 82 300 270 3 50 3 30 350 315 4 00 3 78 400 360 4 50 4 25 450 406 5 00 4 73 500 451 6 00 5 68 600 542 7 00 6 63 700 633 8 00 ...

Page 58: ... x IN 0 2 s 0 4 s Breaking Current IA 10 x IN 0 2 s 0 4 s Breaking Current IA 20 x IN 0 2 s 0 4 s Breaking Current IA 12 x IN 0 1 s Limit Value A Min Dis play A Limit Value A Min Display A Limit Value A Min Display A Limit Value A Min Display A Limit Value A Min Display A Limit Value A Min Display A 2 9 2 10 16 17 10 11 20 21 40 42 24 25 3 14 1 15 24 25 15 16 30 32 60 64 36 38 4 19 20 32 34 20 21 ...

Page 59: ...ed parts of a machine at which more than 60 V are pres ent during operation must drop to a value of 60 V or less within a period of 5 seconds after supply voltage is switched off Function Test The machine is operated with nominal voltage and is tested for correct functioning in particular for correct safety functions Special Tests Pulse control mode for troubleshooting with PROFITEST 204HP HV only...

Page 60: ...on nected to the protective conductor and which comply with re quirements for housing leakage current and if applicable patient leakage current e g data processing devices with shielded power pack Note 2 Permanently connected devices with protective conductor Note 3 Portable x ray devices with mineral insulation Key IB Housing leakage current probe or contact current IDI Residual current ISL Prote...

Page 61: ...ctrode loop resistance Low Value Resistance at Protective Earthing and Bonding Con ductors RLO Bonding conductor resistance pole to PE RLO Bonding conductor resistance pole to PE Insulation RE INS Earth leakage resistance DIN 51953 RINS Insulation resistance RST Standing surface insulation resistance ZST Standing surface insulation impedance Current IA Breaking current IL Leakage current measured ...

Page 62: ...l Line Voltage Display of UL N 26 Non Trip Test 18 P Phase Sequence 14 PRCD K 19 PRCD S 20 R RCD S 19 Rechargeable Batteries Insertion 6 Level Indicator 3 Testing 6 S SCHUKOMAT 20 Select system type TN TT IT 22 SIDOS 20 SRCD 20 Standard DIN EN 50178 VDE 160 18 DIN EN 60 204 59 DIN VDE 0100 23 29 DIN VDE 0100 Part 410 19 DIN VDE 0100 Part 600 5 DIN VDE 0100 Part 610 25 DIN VDE 0100 Teil 610 17 EN 1...

Page 63: ...a Richard Pflaum Verlag www pflaum de Revised 2005 ISBN 3 7905 0924 8 Prüfungen vor Inbetrieb nahme von Niederspan nungsanlagen Kammler M Nienhaus H Vogt D VDE Verlag GmbH www vde verlag de VDE publication series Volume 63 2nd 2004 issue Schnelleinstieg in die neue DIN VDE 0100 410 Schutz gegen elektr Schlag Hörmann W Nienhaus H Schröder B VDE Verlag GmbH www vde verlag de VDE publication series V...

Page 64: ... are capable of completing repairs using original replacement parts As a full service calibration laboratory we can calibrate instruments from other manufacturers as well 22 Recalibration The respective measuring task and the stress to which your mea suring instrument is subjected affect the ageing of the compo nents and may result in deviations from the guaranteed accuracy If high measuring accur...

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