YOKOGAWA MY40 User Manual

Store this manual in an easily accessible place
for quick reference.
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)

YOKOGAWA MY40 Specifications

General

Brand	YOKOGAWA
Model	MY40
Category	Test Equipment
Language	English