MULTI MEASURING INSTRUMENTS MLIT-1 User manual

LIVE INSULATION TESTER
MLIT - 1
INSTRUCTION MANUAL
Thank you very much for selecting our model MLIT-1
Live Insulation Tester.
Before use the instrument, read this instruction
manual completely and familiarize yourself thoroughly
with all functions.
Keep this instruction manual carefully to take out
whenever you need.
MULTI MEASURING INSTRUMENTS CO., LTD
Akihabara Murai Bldg. 7F, 1-26 Kanda Sakuma-cho,
Chiyoda-ku, Tokyo, Japan, 101-0025
TEL : [phone] FAX : [phone]
Home Page: http://www.multimic.com/
E-mail: multi@multimic. com

SAFETY SUMMARY observe by all means
●To use this instrument safely, read this " SAFETY SUMMARY " carefully and apply
the instrument correctly.
●The CAUTIONs and WARNlNGs which appear on the following pages are stared to
prevent the operator & other people from the dangers and their properties from the
damages beforehand.
△
!WARNlNG : This symbol indicates the contents " Possibilities of the death
or the serious wound can be supposed " caused from
mis-operations.
△
！CAUTION : This symbol indicates the contents " Possibilities of the injury or
only the material damage can be supposed" caused from
mis-operations.
○ OPERATION ENVIRONMENT
△
!CAUTION
● Do not use or storage this instrument under the condition of direct rays of the
sun, high temperature & humidity and or condensation, as it may cause the
deformation and or the isolation defect of the instrument.
●Do not us this instrument in the environment influenced by acids, alkalis,
organic solutions. corrosive gas, etc.
●Do not use or storage this instrument where the mechanical vibration can be
directly transmitted, as it may cause defect of the instrument.
● Do not use this instrument nearby the appliances which generate strong
magnetic field and or electrified, as it may cause mis-movement of the
instrument.
● This instrument does not have the water / dust-proof structure. Do not use this
instrument in the environment with a lot of dust and drops of water, as it may
cause defect of the instrument.
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○ OPERATION CONDITION & CONNECTlON
△
!WARNlNG
POSSIBLE ELECTRICAL SHOCK
●This instrument is for the use of low voltage circuit.
Do not make measurements of power lines carrying more thanAC500V.
Before use, check and confirm the voltage of circuit to be measured.
●Apply only the coated cables and do not clamp bare cables.
POSSIBLE ELECTRICAL SHOCK OR ACCIDENT
●Do not handle the instrument in the rain, at humid place, with a drop of water
and or with wet hands.
● Do not use the instrument if the CT or CT case are damaged and if something
is wrong with the CT cables.
● When replacing the batteries, remove the instrument from all measuring
circuits.
●Do not load the voltage exceeding AC10V to the input & output terminals of
instrument body.
△
!CAUTION
FOR SAFETY USE
●Do not drop the instrument & CTs and or do not give the strong shock .
●Do not put heavy goods on the cables of instrument, CTs & Accessories and
do not modify those cables.
●If dropping CTs and or giving strong shock, the joint surface of CTs are
damaged and it may cause wrong influences to the measurement.
●To avoid defect of CTs due to the break of cables, do not bend and or pull the
cables at the base of CTs. Handle them very carefully.
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1. GENERAL
This instrument is the world first Live Line Clamp Insulation Resistance Tester which
can measure insulation resistances of motors, electric appliances and circuits by
clamping CT to the live lines. Formerly, the insulation resistances of motors, etc. have
been measured after disconnected the power lines but nowadays, the insulation
measurements are getting more & more difficult, as there are so many places where
we cannot cut down the electricity easily.
The model MLIT-1 applied the super precision split-core type ZCT and enabled the
insulation resistance measurement up to 20MΩ, which has been mostly impossible
by clamping CT.
2. SUGGESTIONS BEFORE USE
After opening the package, inspect the appearance of the instrument and check the
accessories.
If you find any damage of appearance and or the lack of accessories, inform to the
dealer you bought the instrument.
( COMPOSITION)
InstrumentBody ･･･1
DetectionCT ･･･1
Voltage Input Sensor ･･･1
CarryingCase ･･･1
Instruction Manual ･･･1
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3. SPECIFICATIONS
1) INPUT PART
(1) VOLTAGE INPUT (PHASE VOLTAGE)
① Input Method : Direct Input by Test Leads
② Input Impedance : more than 1MΩ
③ Input Voltage Range : AC50V～AC500V
④ Input Frequency : 50Hz or 60Hz by Switch
⑤ Minimum Resolution : 0.1V
(2) CURRENT INPUT (GROUNDING LINE CURRENT)
①Input Method : Split-Core Type ZCT
2) CURRENT DETECTION PART
① Inside Diameter of CT :Φ30mm
② Method : Split-Core Type ZCT
③ Structure : Manual Slide Method
④ Withstanding Voltage : AC2000V, 1 Minute
⑤ Length of Cable : 2000mm
⑥ Dimension & Weight : 29.6 x 90.2 x 70.7mm, Approx. 200g
3) MEASUREING PART
①Measuring Function : AC Voltage, Line Current, Leakage Current,
Resistive Leakage Current (Ior), Insulation Resistance
②Measuring Method : Clamp CT Method
③Measuring Range : Leakage & Line Current (Auto-range)
0～200μA/ 2mA/ 20mA / 200mA
AC Voltage : 0～500.0V (1 range)
Insulation Resistance : Calculation by Current & Voltage
④Input Frequency : 45～65Hz (by Frequency Change Switch)
⑤Minimum Resolution : Leakage, Line, Ior Current : 0.1μA
AC Voltage : 0.1V
⑥ AC Detection Method : Average Sensing RMS Conversion
⑦ A/D Conversion : Successive Comparison Method
⑧Display : Max. 1999 Count LCD with Annunciators
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⑨SamplingRate :2times/second
⑩Over Range : ｢OL｣mark on LCD
⑪DataHold : ｢DH｣mark on LCD and Holding Data
⑫tanδMeasurement : By ｢tanδ｣ ON, display insulation resistance calculated
with tanδvalue
⑬LowBattery : ｢B｣mark on LCD
⑭Auto Power Off :Automatically power off approx. 10 minutes after the final
key operation
⑮Memory Function : The displayed value can be storaged into the internal
memory and they can be taken out on the display if
necessary.
There are also “all clear mode”, etc.
4) GENERAL SPECIFICATION
①Circuit Voltage to be applied : Less thanAC500V (Insulated Conductor)
②Operating Temperature : 0℃～50℃, ＜85%RH (Non-condensing)
③Storage Temperature : －l0℃～60℃, ＜85%RH (Non-condensing)
④Withstanding Voltage : AC2000V / 1 minute between CT part and
InstrumentBody
⑤Power Supply : Alkaline Battery (LR6 x 4 pcs.)
⑥Consumption Current : Approx. 15mA (Approx. 110 hours / continuous
use)
⑦Dimension & Weight : 78(W) x 155(H) x 32(D) mm, approx. 300g.
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ACCURACY ( 23℃±5℃, Less than 85%RH )
Leakage Current (Io), Line Current (I), Resistive Leakage Current (Ior)
rdg : reading dgt : digit
Range Resolution Accuracy (50Hz / 60Hz)
Voltage (V) 0.1V 0～499.9V ±1.0%rdg±10dgt
I, Io 200μA 0.1μA 0～199.9μA ±1.0%rdg±10dgt
2mA 0.001mA
0.200～1.999mA ±1.0%rdg±10dgt
20mA 0.01mA 2.00～19.99mA ±1.0%rdg±10dgt
200mA 0.1mA 20.0～220.0mA ±1.0%rdg±10dgt
Ior 200μA 0.1μA 0～199.9μA ±1.5%rdg±15dgt
2mA 0.001mA
0.200～1.999mA ±1.5%rdg±15dgt
20mA 0.01mA 2.00～19.99mA ±1.5%rdg±15dgt
200mA 0.1mA 20.0～220.0mA ±1.5%rdg±15dgt
※ Accuracy with the condition that the conductor to be measured is located in the center
of CT.
※ AC Conversion Method : Average Sensing RMS conversion
※ Accuracy of Ior : In case of single phase (1Φ), the phase angle of voltage & current
should be 0°.
Incaseof3phase/3wires(△), the phase angle of voltage &
current at △wiring should be 300°.
※Use frequency select switch at the time of measurement.
※ The insulation resistance values are figured out by formulas between voltage &
current (Ior) at each wiring system.
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4. NAME & FUNCTION OF EACH PART
①Clamp Type ZCT : Current detection Sensor
②Open / Close Lever : ZCT will be opened, when pushing up the both
levers and pulling CT to arrow directions.
③ZCT Output Plug : to be connected with instrument body.
④CT Input Terminal : Insert ZCT plug into the terminal.
⑤Power Switch (POWER) : Power on by pressing the switch and power off by
pressing once more.
⑥ Voltage Select Switch (～V) : By pressing this switch, the voltage value will be
displayed.
⑦Current Range Switch (～I) : By pressing this switch, Io current value will be
displayed. By pressing once more, Ior of 1Φand
by pressing three times, △Ior, and by pressing
once more, Y Ior value will be displayed. Select
the correct range according to wiring system and
or circuit to be measured. The sing of present
range will be showed on the display ( in case of
no sign, the displayed value in Io ).
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⑧Insulation Resistance Switch (MΩ) : By pressing this switch, the insulation
resistance value calculated by voltage
and Ior value will be displayed. When
voltage is not inputted, the display will
become “OL”. Fix the wiring system
correctly. By once for 1Φ, twice for △
and three times for Y.
⑨LCD Display (LCD) : Showing the measured values, measuring mode,
conditions of battery, etc.
⑩Data Hold Switch (D-HOLD) : By once press, ｢DH｣mark will be displayed.
(MEM CLR) At the same time, the empty block number will be
displayed and the displayed value will be
memorized in the displayed block by pressing
｢ENT｣switch. By pressing ｢DH｣switch again
without ｢ENT｣switch, Data Hold function will be
released.
⑪Empty Switch (ENT) : This switch is for memorization of displayed values.
⑫Frequency Change Switch : Set according to power supply frequency.
⑬RIGHT･tanδON Switch : Press this switch to measure Ior current and MΩ
by calcurating tanδand “tanδ” mark will be
blinking on the display. During MEMORY ON, press
this switch to change the first ordinal number and it
will be blinking.
⑭LEFT･tanδOFF Switch : Press this switch to release “tanδ” display and “tan
δ” will become non-blinking. During MEMORY ON,
press this switch to change the tenth ordinal
number and it will be blinking.
⑮UPSwitch :Tomemorizethedisplaydata,pressthisswitchto
set the memory number. During MEMORY ON,
press this switch to select the memory number to
be recalled.
⑯DOWN Switch : Use this switch to set the memory number together
with UP Switch.
⑰Voltage Input Terminal (～V INPUT) : To measure Ior current, input voltage to this
terminal (black one is Ior the grounding
side).
⑱Battery Cover (Rear Side) : Remove this cover to change the batteries.
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5. OPERATION PROCEDURE
5-1) CHANGE OF BATTERIES
Confirm that the power is "OFF".
Take out the instrument from
carrying case and remove the Screw to
screw of battery cover by ○
+fix the cover
driver. Slide the battery cover to
the arrow direction and remove
the battery cover. Take out 4
batteries and replace them.
Putthebatterycoverbackto Batterycover
the original position and tighten
the screw.
･｢B｣sign will appear on the display when batteries are exhausted and get less than
operation voltage. Replace to new batteries immediately.
･Do not use the batteries mixed new one and once used and or different kind ones.
△
! WARNING
POSSIBLE ELECTRICAL SHOCK
●When removed the battery cover, put it back to the original position certainly. Do
not operate the instrument, leaving the battery cover off.
●Do not replace the batteries with clamping CT to the conductor.
△
! CAUTION
POSSIBLE DAMAGE TO THE INSTRUMENT
●When not using the instrument for a long period, remove the batteries and keep
separately. The batteries may leak and may cause damage to the instrument.
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5-2) MEASUREMENT
To use the instrument safely, follow the contents described in WARNING and CAUTION
without fail.
△
! WARNING
POSSIBLE ELECTRICAL SHOCK
●For safety, use the instrument in circuit less than 500V.
Before operation, confirm the circuit voltage to be used.
POSSIBLE ELECTRICAL SHOCK OR ACCIDENT
●Do not handle the instrument in the rain, at humid place, with a drop of water and
or with wet hands.
●Do not use the instrument if the CT or CT case are damaged.
●Do not use the instrument, leaving the battery cover off.
POSSIBLE FIRE HAZARD AND BURN ACCIDENT
●Part of ZCT will get heat when applying excessive current.
Do not apply more than maximum capable current (10Arms) to ZCT part.
●Do not apply more than AC 500V to voltage input terminal (～V INPUT)
Note :
・ In case of input “0” at Ior range, the display will not become completely “0” but it is
not defect.
・ Connect the grounding phase to the black voltage input terminal. Otherwise, Ior
value will have error from the influence of electric fields.
- 10 -

(1) Measurement of Line Current
Conductor to be
measured
①Connect ZCT to CT INPUT of the instrument
like as the drawing.
②Press POWER SWITCH ⑤on. Once all display
will be lightened and then, the voltage display
will appear.
③Once press CURRENT RANGE SWITCH ⑦and
then, the display become for current.
④Set FREQUENCY CHANGE SWITCH ⑫to power
supply frequency of the conductor to be measured.
⑤Open ZCT and Clamp it to the conductor to be
measured and then close ZCT.
⑥Read the display value. To memorize the displayed
value, press D･HOLD switch ⑩to get Data Hold
mode. Then, press ENT switch ⑪and the data
will be memorized. Not to make memorization,
press D-HOLD Switch once again to release the
data hold function. (In case of over range, ｢OL｣
mark will be displayed).
Note :
・ The instrument has auto power off function and the power will get off approx. 10
minutes after the final switch operation.
・ At Ior measurement mode, line current cannot be measured.
(2) Measurement of Leakage Current
①Measurement of Leakage Current of Grounding Line
The operations are the same as for line current measurement.
②Measurement of Leakage Current except of Grounding Line
The operations are the same but clamp CT to 2 wires at the same time in case of
single phase / 2 wires and clamp 3 wires or 4 wires at 3 phase / 3 wires or 4 wires.
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(3) Measurement of Resistive Leakage Current (Ior) & Insulation Resistance (MΩ)
CAUTION FOR MEASUREMENT
●This instrument measures insulation resistance at live line and sometimes, the
measurement values may get different form ordinary insulation resistance
testers.
● The voltage inputs for the measurement of circuit insulation resistance are
different according to single phase / 2 wires, three phase / 3 wires and three
phase / 4 wires. Refer to the wiring systems and use the instrument correctly.
● Also, be careful that the wiring system is different according to the kind of motors.
● Pay sufficient attention to the wiring in case of measurement of Ior (MΩ), as the
instrument regards phase factors of current & voltage. Also, the current
measurement cannot be done if mistaking the frequency setting, as the phase
factors are changed.
△
!WARNlNG
●Do not apply more than AC500V to voltage input terminal (～V INPUT).
It may cause the damage.
POSSIBLE ELECTRICAL SHOCK
● The test leads are consumption articles. Before connecting to the instruments,
confirm that there are no damage at the insulated coating of test leads. If you
found any unusualness, immediately stop the operation and repair or change to
new ones.
POSSIBLE FIRE HAZARD AND BURN ACCIDENT
● Connect the test leads firmly. The connection error may cause the spark.
● Do not apply the voltage more than 10V to CT INPUT terminal absolutely.
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① Press POWER switch ⑤once. All display appears and then, becomes voltage
display.
② Connect ZCT to CT INPUT and test leads to ～V INPUT according to each color.
③ According to the circuit and apparatus to be measured, input the voltage and
current to the instrument. Refer to wiring method for voltage & current input.
④ By frequency change switch, set the power supply frequency to be measured.
⑤ Confirm the voltage value on display and once press current range switch. The
display becomes Io current. Confirm Io current value and press current range
switch once again. The display becomes 1Φ/ Ior showing Ior current of single
phase. Measure Ior current value by pressing current range switch according to
wiring system to be measured.
By pressing current range switch :
Io IΦ/Ior △/Ior Y/Ior
press press press press
In order to consider tanδ, once press tanδON switch ⑬, “tanδ” appears on the
display. To get back before, press tanδOFF switch ⑭and “tanδ” disappears.
⑥ To measure the insulation resistance (MΩ), once press insulation resistance
switch. In case of no voltage input, the display becomes “OL”.
⑦ In order to memorize Ior current or MΩvalues, press D-HOLD switch ⑩and
then, press ENT switch ⑪at each time.
(WIRING SYSTEM)
○
a 1P/1W, 1P/3W CIRCUIT : Wiring Mode 1Φ/Ior
- 13 -

○
b 3P/ 3W CIRCUIT : Wiring Mode △/Ior
○
c 3P / 4W CIRCUIT : Wiring Mode Y/Ior
- 14 -

○
d AC SERVOMOTOR : Wiring Mode 1Φ/Ior
○
e INVERTER MOTOR : Wiring Mode 1Φ/Ior
- 15 -

5-3) MEMORY FUNCTION
This instrument has memory function and can memorize the measured data and can
display such memorized data in LCD.
(1) How to memorize
Flashing
Memory No.
① During the measurement of voltage, Io current,
Ior current and or MΩ, once press D-HOLD
switch ⑩. ｢DH｣mark appears on the display
and memory number is flashing.
By pressing ENT switch ⑪, the data will be
memorized into the flashing memory number.
※ In case of choosing own favorable numbers, decide the number by using UP, DOWN,
RIGHT, LEFT switches (⑬～⑯) and then, press ENT switch ⑪.
※ If you use the memory number which has data already, the old data will be deleted
and the new one will be memorized.
(2) How to see the memorized data on the display (MEMORY ON MODE)
① Pressing LEFT switch ⑭and RIGHT switch ⑮, push POWER switch ⑮.
② No. 1 data will be displayed. By using UP, DOWN, RIGHT, LEFT switches ⑬～⑯,
set the favorable memory number and read the data.
③ To delete the data on the display, press MEMCLR switch. The data will be
disappeared and only the memory number will remain.
④ To terminate MEMORY ON MODE, push POWER switch ⑤once again.
(3) How to delete all memorized data (MEMALL CLR MODE)
① Pressing D-HOLD switch ⑩and ENT switch ⑪, push POWER switch ⑤.
② Memory number on the display, get incliment and all data will be deleted.
③ Push POWER switch ⑤once again.
Note
Be careful sufficiently not to delete memorized data mistakenly.
- 16 -

5-4) USE OF SPLIT-CORE TYPE ZCT (ZCT-30SP)
(How to open/close) UP & DOWN LEVER
① Push up and down levers by fingers
and pull CT to the arrow directions
like as drawing.
② When clamping CT to the conductor
to be measured, join left & right side
slowly and push them up until up &
down levers get clicked completely.
△
!CAUTION
1. The secondary side of the ZCT is open. When clamping CT to the
conductor without inserting to the instrument, voltage will occure at the
secondary side, which may cause danger. In case of clamping ZCT to the
conductor to be measured, definitely insert the output plug to the
instrument beforehand.
2. This ZCT is the highest precise product and treat it very carefully. Keep
this ZCT closed, as it is fragile if leaving CT open.
- 17 -

6. REPAIR SERVICE
When requesting for repair service, Please bring the instrument directly to the dealer
where you bought.
When mailing the instrument, always pack it in its original or equivalent packing
materials to avoid any damage during the transportation and also put together with
documents showing your name, address, phone number and defect point.
7. WARRANTY
This instrument is sent out from our factory after the sufficient internal inspections but
if you find any defect due to the fault in our workmanship or the original parts, please
contact the dealer where you bought the instrument.
The warranty period is 12 months from the date of purchase and the instrument shall
be repaired at free of charge, provided that we judge the cause of defect is obviously
resulted from our responsibility.
GUARANTEE REGULATIONS
1. This instrument is warranted for the operation under normal use for 12 months from
the date of purchase.
2. This warranty does not cover the following defects:
a. Defect caused from the improper use and operation.
b. Defect caused from the use, operation and storage beyond the original
specifications, designs and conditions.
c. Defect caused from the renovations or repairs done by someone else than us
or our representatives.
d. Defect not caused from our responsibilities.
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