YOKOGAWA MY40 User manual

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User's
Manual
2nd Edition: October 2017 (YMI)
All Rights Reserved. Copyright ©
2015, Yokogawa Meters & Instruments Corporation,
2017, Yokogawa Test & Measurement Corporation
A3
Printed in China
9. Display Functions
Lit when the measured insulation
resistance is being held.
Flashes when the battery voltage is low.
Lit when the rating setting is
1000 V/2000 MΩ.
Lit when the rating setting is
500 V/2000 MΩ
Lit when the rating setting is
250 V/200 MΩ.
Lit when the rating setting is
125 V/200 MΩ.
Indicates overrange (OL). Indicates the extension bar graph.
Change toward smaller values
Change toward larger values
Stable
Sub-display
Indicates:
• Comparator setting value or
the storage number; or
• The storage number for memory.
Indicates the unit for
insulation resistance for comparator.
Lit when:
• Pressing the MEAS key in
insulation resistance measurement; and
• Residual electrical charges are present
during discharging.
Lit when the comparator is activated.
Lit when the measured
insulation resistance is lower than
the comparator setting value.
Lit when the memory feature is in use.
Indicates the unit for
AC voltage measurement.
Indicates the unit for insulation resistances.
Indicates the unit for
conductor resistance measurement.
Indicates the continuity mark,
which is lit when the measured
insulation resistance is lower than 40 Ω.
The extension bar graph shows how
the measured value is changing
(trend) as follows:
Note that the number of marks means
the degree of change.
■ Overrange Display Functions
OL Display
The tester displays the OL mark when the measured resistance exceeds
the following values.
Insulation resistance measurement:
  For1000Vand500Vratings:2000MΩ
  For250Vand125Vratings:200MΩ
 Conductorresistancemeasurement:400Ω
Display
The tester displays the mark when the internal calculation exceeds
the following values.
Insulation resistance measurement:
  For1000Vand500Vratings:approx.4000MΩ
  For250Vand125Vratings:approx.400MΩ
Change to Upper/Lower Ranges
•Toupperrange
When the digital reading exceeds 4000,
the measuring range changes to the next upper range.
•Tolowerrange
When the digital reading falls below 360,
the measuring range changes to the next lower range.
Lower Resolution Display
If the digits below the decimal point are not stable,
they can be automatically omitted to limit the resolution.
10. Before Measurement
1. Safety
•Readthehandlingprecautionsinthismanualcarefully.
•Makesureitissafebeforestartingmeasurement.
2. Battery Voltage Verication
•Makesurethatthebatteryvoltagesarewithinthevalidratings
(i.e. the markisnotashing).
•Ifthebatteriesarelow,replacethemasspeciedinthebatteryreplacement
section of this manual.
NOTE
As the markindicationdependsontheload(currentconsumption),
check that the mark does not appear for the largest load
whenshort-circuitingtheearthprobeandthelineprobe(0MΩ).
3. Connecting the Probes
WARNING
•Removetheprobesfromthemeasuredobjectbeforeattaching/detaching
theprobesto/fromthetester.
•MakesuretheMEASkeyisoffwhenattaching/detachingtheprobesto/fromthetester.
•Plugtheearthprobeintotheearthterminal.
•Plugthelineprobeintothelineterminal.
4. Function Switch Verication
Besuretoconrmthatthefunctionswitchissettothedesiredrating.
5. 1000-V Rating
When measuring with the 1000-V rating,
see section 14.1, “Double-action1000-V Function”.
11. Measuring the Insulation Resistance
11.1 Before Connecting the Probes
WARNING
•Turnoffthepowertothemeasuredobjectbeforeconnectingor
measuring insulation resistance.
•Electricalchargesmaybepresentinthecablesattachedtoormetalof
the electrical equipment being tested. Verify that the equipment is free from
electrical charges before connecting the testing terminals.
•Besuretoconrmthatthefunctionswitchissettothedesiredrating.
ON
OFF
125 V/200 MΩ
250 V/200 MΩ
500 V/2000 MΩ
1000 V/2000 MΩ
Measurement wiring
Insulation resistance ratings:
Power supply side
(primary)
Load side
(secondary)
Set the switch to OFF
Line probe
Earth probe
11.2. Setting the Function Switch
Turn the function switch to the desired measurement rating position.
Theinitialdisplayis“----MΩ”.
11.3 Connecting the Earth Probe
•Ifthemeasuredobjectisgrounded,connecttheearthprobeclipto
themeasuredobject’sgroundline.
•Ifthemeasuredobjectisnotgrounded,thisprocessmaybeomitted.
11.4 Connecting the Line Probe
Bringthelineprobeintocontactwiththemeasuredobject,andthen
press the key. The display indicates the insulation resistance of
themeasuredobject.
NOTE
During measurement, exercise care to prevent the leadwire of the line probe from
comingintocontactwiththeground,oororanyotherobject.
Not observing this precaution may result in a failure to measure the correct
insulation resistance.
11.5 After Measurement
WARNING
•Immediatelyaftermeasurement,electricalchargesresultingfromtheappliedtesting
voltagemayremainpresentintheprobesormeasuredobject.
•Thetester,therefore,isdesignedtoautomaticallybegindischargingelectricityupon
completion of measurement.
VerifythattheALARMLEDturnsoffwhendischargingiscomplete.
12. Measuring AC Voltages
WARNING
• Do not press the MEAS key while measuring AC voltages.
•Voltagethatexceedsthespeciedlimit(600V)mustnotbeappliedtoterminals.
Doingsocausesalldigitsofthemeasuredvoltagetoashandthebuzzertobeep.
12.1 Setting the Function Switch
Turn the function switch to an AC voltage
measurement ( V)position.
12.2 Connecting the Earth Probe
•Ifthemeasuredobjectisgrounded,connecttheearth
probecliptothemeasuredobject’sgroundline.
•Ifthemeasuredobjectisnotgrounded,
this process may be omitted.
12.3 Connecting the Line Probe
Bringthelineprobeintocontactwiththemeasuredobject.
ThedisplayindicatestheACvoltageofmeasuredobject.
Model MY40
Insulation Resistance Tester
[ Operation Manual ]
Thismanualdescribesthespecicationsandhandlingprecautionsof
the insulation resistans tester.
Before using this product, thoroughly read this manual to understand how to use it properly.
 IMMY40-E: Safetyprecautions,componentsandspecicationsetc.
 IMMY40-02EN: Operationmanual(thismanual)
ContactinformationofYokogawaofcesworldwideisprovidedonthefollowingsheet.
 PIM113-01Z2: Inquiries Listofworldwidecontacts
IMMY40-02EN
2ndEdition:Oct.2017(YMI)

IM MY40-02EN <P 2>
<Deleting data>
Data saved can be collectively deleted.
(1) Turnthefunctionswitchfrompower-offtothecontinuitytestposition(Clr)while
pressing and holding the key(MEM).
(2) “MEM”and“CLr”appear.
(3) Pressthe key(MEM).“CLr”startsashing.
(4) Pressthe key(MEM)againwhile“CLr”isashing.
Thebuzzersoundsandalldataaredeleted(donotchangethepositionof
thefunctiondialfortwosecondswhen“CLr”isdisplayed).
The tester changes its mode to measurement of conductor resistances.
NOTE
To stop deleting of data:
Do not perform any key operation and wait for 10 seconds while
the“CLr”indicationmentionedinstep(3)isashing;or
Turn the function switch to another rating.
<Turning off the memory feature>
Turn the function switch to the off position.
14.8 Comparator
When a measured insulation resistance is less than the reference value setting,
the markappearsandthebuzzersounds.Alsothemeasuredvalueis
automatically held for 5 seconds.
<Selecting the reference value>
Selectfromthreepresetvaluesforeachrating.
Defaultvalues:no.01:0.1MΩ/no.02:0.2MΩ/no.03:0.4MΩ
(1) Turnthefunctionswitchtoameasurementrating.
(2) Pressthe key.
(3) “ ”appears and the reference value appears on the subdisplay.
(4) Pressingthe key(Select)changesthereferencevaluedisplayasfollows.
  0.1MΩ→0.2MΩ→0.4MΩ→Comparatoroff(nodisplay)
The reference value currently displayed is selected as the comparator setting.
<Setting the preset values>
Main display
Sub-display
Position of decimal point
Measured
value
Reference
value
Reference
value
no.
Maine
display Sub- display
Comparator setting
Insulation resistance
measurement
(with comparator)
<Setting the preset values>
Eachofthedefaultpresetvaluesno.01tono.03canbechangedindependently.
(1) Turnthefunctionswitchfrompower-offtoadesiredratingwhilepressingand
holding the key.“no.01”onthesub-displayashes.
Pressthe key(Select)toselectno.02orno.03.
(2) Conrmthesettingno.withthe key(Enter).
The reference value on the main display can be set.
(3) Selectthepositionofthedecimalpointwiththe key(Select).
(4) Conrmthedecimalpointwiththe key(Enter).
(5) Selectthenumberforeachdigitsequentially.
Pressingthe key(Select)changesthenumberasfollows.
0→1→2···8→9→0
(6) Conrmthenumberwiththe key(Enter).
(7) Setthenumberforthenextdigit.
(8) Whensettingsforallthedigitsarecomplete,
thereferencevaluestartsashing.
(9) Conrmthereferencevaluewiththe key(Enter).
Thebuzzersoundsandthesettingends.
The tester changes its mode to measurement of insulation resistances.
Repeatsteps(1)to(9)tochangeotherpresetvalues.
NOTE
• To cancel the preset setting
Pressingthe key(Select)instep(8)returnsthesettingproceduretostep(1).
To stop the setting, turn the function switch to the off position.
• To set the preset values for another rating
Turnthefunctiondialtothedesiredrating(insulationresistance)instep(8).
15. Corrective Measures in Case of Failure
If the instrument does not operate properly after taking the corrective measures shown
below or any other failure that is not covered here occurs, contact the vendor from which
you purchased the instrument.
Failures
•Thetesterdisplaysnothingafterturningthefunctionswitchtotheonposition.
•Thedisplayislightincolor.
•Themeasuredvaluesareerroneous.
Items to Check
•Thebatteriesareinstalledproperlyandtheirpowerlevelsarenotlow.
•Themeasuringprobesareconnectedcorrectlyandarenotdamaged.
•Whetherthefailurereoccursafterturningoffthepowerandretryingtheoperation.
Error Messages
Err.0 An internal operation failure.
Turn off the power and retry the operation.
* If the failure reoccurs, the tester needs repairing.
Err.1 Cannot save the comparator or memory settings.
Measurement functions other than the comparator and
memory functions operate normally.
Settingsanddatasavedwithouttheerrorindication(Err.1)canbeused.
* If the failure reoccurs, the tester needs repairing.
Err.2 An internal operation failure.
Turn off the power and retry the operation.
* If the failure reoccurs, the tester needs repairing.
13. Measuring Conductor Resistance (Continuity)
Thetestercanmeasuretheconductorresistanceof0to400Ω.
Thebuzzerbeepsforresistancesapproximately40Ωorlower.
WARNING
Turnoffthepowertothemeasuredobjectbeforeconnectingor
measuring conductor resistance.
13.1 Setting the Function Switch
Turn the function switch to a conductor resistance measurement ( )position.
13.2 Connecting the Earth Probe
Securelyconnecttheearthprobetothemeasuredobject.
13.3 Connecting the Line Probe
Bringthelineprobeintocontactwiththemeasuredobject.
Thedisplayindicatestheresistanceofthemeasuredobject.
NOTE
YoudonothavetopresstheMEASkeywhenyoumeasureconductorresistances.
14. Additional Features
14.1 Double-action 1000-V Function
ThetesterisequippedwiththeRELEASEbuttontoprotectthemeasuredcircuitfrom
damage due to inadvertent measurement at 1000 V.
To select the 1000 V rating, turn the function switch to the position
while pressing this button.
To cancel the 1000 V rating, turn the function switch to the off position or
another rating position.
14.2 Live-line Alarm
Alwaysturnoffthepowertothemeasuredobjectbeforeconnectingormeasuring
insulation resistance. If an AC voltage of more than 40 V is applied,
theALARMLEDashesandthebuzzerbeeps.
In this case, stop the measurement immediately and check the power supply voltage.
14.3 Locking the MEAS Key (for Continuous Measurement)
TheMEASkey,whenpulleduptotheright,canbelockedtoensurethekeyremains
turned on. Use this mechanism when making continuous measurement over
a prolonged period.
Note, however, that leaving the key turned on for an unreasonably long time will
accelerate the discharge of the batteries.
14.4 HOLD Feature
Measured insulation resistances are automatically held for approximately
veseconds.TurningofftheMEASkeyinitiatesholding.
14.5 Auto Power-off
The tester is automatically turned off when no key operations are performed
for 10 minutes.
Thebuzzersounds9andahalfminutesafterthelastkeyoperation(at1-secintervals).
Ifanymeasurementorkeyoperationisnotmadewhilethebuzzersounds,
the tester is turned off. However, it is not turned off when measurement is in
progress or an alarm occurs.
To use the tester after the auto power-off is triggered,
press the key or the key, or turn the function switch to the off
position once before proceeding with the desired operation.
14.6 LIGHT and COMP Keys
The keyisusedastheSelectkeyforsettingsandstoragenumbersof
the comparator and memory functions.
The keyisusedastheEnterkeyforsettingsandstoragenumbersof
the comparator and memory functions.
PressingtheEnterkeywhilethedisplayisashing,conrmsselectionof
the setting or the storage numbers.
<When setting the memory or comparator function>
Turn the function switch to an insulation resistance rating position while
pressing and holding the key or the key until all the displayed
digitsstopashingandremainon,andthebuzzersounds.
Orpositionthefunctionswitchtoaratingoftheinsulationresistancerst,
press the key or the key when all the digits appear,
andholdthekeyuntilthebuzzersounds.
<Backlight>
•Thebacklightremainsoffwhilethecomparatorisset.
•Thebacklightislitwhenmemoryisinuse.
14.7 Memory Feature (Data Saving)
Up to 20 measured values of the insulation resistance for each rating can be
saved to memory.
<Displaying data>
(1) Turnthefunctionswitchfrompower-offtoameasurementratingwhile
pressing and holding the key(MEM).
“MEM”appearsand“no.01”(storagenumber)ashesonthesub-display.
(2) Selectastoragenumber.
Pressthe key(Select)toselectastoragenumber(no.01tono.20).
Ifaninsulationresistancedataissavedwiththeselected(displayed)number,
the insulation resistance value is displayed.
Ifanydataisnotsavedwiththeselected(displayed)number,“----”isdisplayed.
<Saving data>
Firstselectastoragenumberasinsteps(1)and(2)above.
Overwriting data is possible.
(3) Performmeasurementwiththe key.
(4) Turnoffthe key.
Themeasuredvalueisheldandstartsashing.
Pressthe key(Enter)whilethemeasuredvalueisashingtosave
ittomemory(itisheldforvesecondsinwhichtimethenextdatacannotbesaved).
NOTE
If the data being held is invalid, “----” is displayed and it cannot be saved.
In this case, perform measurement again and save the data.