KYORITSU 3131A User manual

MODEL 3131 A
ANALOGUE INSULATION / CONTINUITY TESTER
INSTRUCTION MANUAL
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

Contents
1. Safety Warnings .................................................................................... 1
2. Features ............................................................................................... 5
3. Specifications ...................................................................................... 6
4. Instrument Layout ................................................................................. 8
5. Preparation for Testing......................................................................... 10
5-1 Removing the Cover ...................................................................... 10
5-2 Mechanical Zero Adjustment .......................................................... 11
5-3 Battery Voltage Check ................................................................... 11
5-4 Test Probe Connection .................................................................. 11
5-5 Test Probe Check ......................................................................... 11
6. Operation ........................................................................................... 12
6-1
Disconnection and Check of Power Source of Circuit Under Test ................ 12
6-2 Insulation Resistance Measurement ................................................ 13
6-3 Continuity Testing (Resistance Tests) ............................................. 14
6-4 Continuous Measurement .............................................................. 15
7. Back Light Function ............................................................................ 16
8. Battery & Fuse Replacement ............................................................... 17
8-1 Battery Replacement ...................................................................... 17
8-2 Fuse Replacement ........................................................................ 17
9. Notes on Accessories .......................................................................... 18
9-1 How to Fit Strap Belt & Test Probe Pouch ........................................ 18
10. Cleaning of the Instrument .................................................................... 19
11. Service ............................................................................................... 19
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 1 —
This instrument has been designed, manufactured and tested according to IEC
61010: Safety requirements for Electronic measuring apparatus, and delivered in
the best condition after passed the inspection. This instruction manual contains
warnings and safety rules which must be observed by the user to ensure safe
operation of the instrument and retain it in safe condition. Therefore, read
through these operating instructions before using the instrument.
#WARNING
●Read through and understand the instructions contained in this manual
before using the instrument.
●Keep the manual at hand to enable quick reference whenever necessary.
●The instrument is to be used only in its intended applications.
●Understand and follow all the safety instructions contained in the manual.
It is essential that the above instructions are adhered to. Failure to follow
the above instructions may cause injury, instrument damage and/or damage
to equipment under test. Kyoritsu is by no means liable for any damage
resulting from the instrument in contradiction to these cautionary notes.
○The symbol #indicated on the instrument, means that the user must refer
to the related parts in the manual for safe operation of the instrument. It is
essential to read the instructions wherever the symbol appears in the manual.
#DANGER ：
is reserved for conditions and actions that are likely to
cause serious or fatal injury.
#WARNING
：
is reserved for conditions and actions that can cause
serious or fatal injury.
#CAUTION
：
is reserved for conditions and actions that can cause injury
or instrument damage.
1. SAFETY WARNINGS
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 2 —
Please refer to following explanation of the symbols used on the instrument and
in this manual.
#User must refer to the explanations in the instruction manual.
Caution, risk of electric shock.
Instrument with double or reinforced.
Protection against wrong connection is up to 440V.
EARTH GROUND
This instrument satisfies the marking requirement defined in the WEEE
Directive 2002/96/EC. This symbol indicates separate collection for
electrical and electronic equipment.
#DANGER
●
Confirm a proper operation of the instrument with a well-known power supply.
●Do not use this instrument on energized (LIVE) circuits.
●
Do not attempt to make measurement in the presence of flammable gasses.
Otherwise, the use of the instrument may cause sparking, which can lead
to an explosion.
●Do not make measurement when thunder is rumbling. If the instrument is
in use, stop the measurement immediately and remove the instrument
from the measured object.
●Never attempt to use the instrument if its surface or your hand is wet.
●Never open the battery compartment cover and the instrument case when
making a measurement.
●Do not exceed the maximum allowable input of measuring ranges.
●
The instrument is to be used, only in its intended applications or conditions.
Otherwise, safety functions equipped with the instrument doesn't work,
and instrument damage or serious personal injury may be caused.
●Always Keep your fingers and hands behind the protective fingerguard on
test probe to avoid the possible shock hazard.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 3 —
#WARNING
●Never attempt to make any measurement, if the instrument has any
structural abnormality such as cracked case or exposed metal parts.
●Do not turn the range selector switch while the test probe are connected
to the circuit under test.
●Do not install substitute parts or perform any unauthorized modification of
the instrument. Return the instrument to Kyoritsu or your distributor for
service and repair to ensure the safety features are maintained.
●Do not try to replace the batteries and fuse if the surface of the
instrument is wet.
●Firmly insert the plug into the terminal when using test probe.
●Make sure to disconnect the test probe from the instrument before
opening the battery compartment cover for battery and fuse replacement.
●Stop using the test lead if the outer jacket is damaged and the inner metal
or color jacket is exposed.
#CAUTION
●Always make sure to set the range selector switch to the appropriate
position before making measurements.
●Do not expose the instrument to the direct sun, dew fall or extreme
temperature and humidity.
●When the instrument will not be in use for a long period of time, place it in
storage after removing batteries.
●Use a damp cloth soaked in water or neutral detergent for cleaning the
instrument. Do not use abrasives or solvents.
●Keep your fingers and hands behind the protective fingerguard during
measurement.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 4 —
Measurement categories (Over-voltage categories)
To ensure safe operation of measuring instruments, IEC 61010 establishes
safety standards for various electrical environments, categorized as O to CAT IV,
and called measurement categories.
Higher-numbered categories correspond to electrical environments with greater
momentary energy, so a measuring instrument designed for CAT III environments
can endure greater momentary energy than one designed for CAT II.
O : Circuits which are not directly connected to the mains power supply.
CAT II : Primary electrical circuits of equipment connected to an AC
electrical outlet by a power cord.
CAT III : Primary electrical circuits of the equipment connected directly to
the distribution panel, and feeders from the distribution panel to
outlets.
CAT IV : The circuit from the service drop to the service entrance, and to the
power meter and primary overcurrent protection device (distribution
panel).
O: Device which is
not directly
connected to the
mains power supply
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 5 —
2. Features
MODEL-3131A is an analogue insulation tester with five ranges for insulation
resistance measurement and continuity testing (resistance tests) of low voltage
installations.
●Designed to safety standards:
IEC61010-1
IEC61010-031
IEC 61557-1,2,4,10
●Dust and drip proof constrution to IP54
●Three insulation test ranges : 250V/100MΩ, 500V/200MΩ, 1000V/400MΩ
●Two continuity test ranges : 2Ω, 20Ω
●Back light function to facilitate work at night or dimly lit locations
●Easy for battery check
●Power-on indication LED lighting during battery check and measurement
●Live circuit warning indication with LED lighting and the buzzer sound
●Fuse protected.
●Color coded scales and range switch position for easy reading
●Uses only 6× 1.5V battery type R6, AA or equivalent
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 6 —
3. Specifications
●Measuring Range and Accuracy (at 23±5℃, relative humidity 45-75%)
Insulation Resistance Ranges:(IEC 61557-2)
Nominal Output Voltage 250V 500V 1000V
Measuring Ranges
Open-Circuit
Voltage
Short-Circuit
Current
Nominal Current
Accuracy
0 - 100MΩ
250V DC +20% max.
1.3mA approx
1mA DC min.
at 0.25MΩ
±5% of indicated value
at 0.1MΩ- 10MΩ
±0.7% of scale length at ranges other than above ranges
0 - 200MΩ
500V DC +20% max.
1mA DC min.
at 0.5MΩ
±5% of indicated value
at 0.2MΩ- 20MΩ
0 - 400MΩ
1000V DC + 20% max.
1mA DC min.
at 1MΩ
±5% of indicated value
at 0.4MΩ- 40MΩ
Continuity Test (Resistance Test) Ranges:(IEC 61557-4)
Ranges
Measuring Ranges
x 1Ω
0 - 2Ω
x 10Ω
0 - 20Ω
Open-Circuit Voltage
Measuring Current
Accuracy
Zero Adjustment Range
4 - 9V DC
200mA DC min.
±3% of scale length
0.2Ωmin.
Ranges
250V/100MΩ
500V/200MΩ
1000V/400MΩ
Measuring range to keep operating instrumetal uncertainty Maximum percentage operating instrumetal uncertainty
0.1MΩ- 10MΩ
±30%0.2MΩ- 20MΩ
0.4MΩ- 40MΩ
Ranges
x1Ω
x10Ω
Measuring range to keep operating instrumetal uncertainty Maximum percentage operating instrumetal uncertainty
0.2Ω- 2Ω±30%
2Ω- 20Ω
Operating instrumetal uncertainty
Insulation Resistance Ranges(IEC 61557-2)
Continuity Test (Resistance Test) Ranges(IEC 61557-4)
The influencing variations used for calculating the operating instrumental uncertainty are
denoted as follows:
Temperature : 0℃and 35℃
Supply voltage : 6.5V to 10.4V
Position : Reference position ±90°
※Prior to measurement, apply Zero Adjustment at each position
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 7 —
Typical Number of Measurements (central tendency for supply voltage up to
6.5V)
Insulation Resistance Ranges:
1000V/400MΩRange Approx. 500 times min.
500V/200MΩRange Approx. 1300 times min.
250V/100MΩRange Approx. 1800 times min.
Continuity Test (Resistance Test) Ranges:
x1ΩRange/ x 10ΩRange Approx. 1000 times min.
Applicable Standards
IEC 61010-1. -2-030 Measurement CAT Ⅲ300V Pollution Degree 2
IEC 61010-031 Safety requirements for hand-held probe assemblies
IEC 61557-1,2,4 Measuring equipment for low voltage distribution systems
IEC 61326-2-2 EMC
IEC 60529 (IP54) Dust & drip proof
EN 50581 (RoHS)
Used location altitude 2000m or less
Operating Temperature & Humidity: 0-40℃, relative humidity up to 85%
Storage Temperature & Humidity: -20-60℃, relative humidity up to 85%
Insulation Resistance More than 50MΩat 1000V DC between
electrical circuit and housing case
Withstand Voltage 3470V AC for five seconds between electrical
circuit and housing case
Overload Protection
Insulation resistance ranges: 1000V Range 1200V (DC) for 10 seconds
500V Range 600V (DC) for 10 seconds
250V Range 300V (DC) for 10 seconds
Continuity ranges: x 1Ω/ x 10ΩRange 440V (AC p-p) for 1minute
Dimensions: 185(L) x 167(W) x 89(D) mm approx.
Weight: 860g approx. (including batteries)
Power Source: 6 x 1.5V battery type SUM-3, R6 , AA or equivalent
Accessories Test Probe MODEL7122B x 1 set
Strap belt x 1
Test probe pouch x 1
R6P AA batteries x 6
Spare fuse F 500mA/600V x 1
Instruction manual x 1
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 8 —
4. Instrument Layout
①METER MOVEMENT ZERO ADJUST ②TEST BUTTON
③SCALE PLATE ④LIVE CIRCUIT WARNING LED
⑤POWER-ON INDICATION LED ⑥CONTINUITY ZERO ADJUST
⑦LIGHT SWITCH ⑧RANGE SELECTOR SWITCH
⑨TEST PROBE (RED) LINE PROBE ⑩TEST PROBE (BLACK) EARTH PROBE
⑪ALLIGATOR CLIP (BLACK) ⑫PROTECTIVE FIGERGUARD
Fig.1 Part names
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 9 —
Protective fingerguard：
It is a part providing protection against electrical shock and ensuring the minimum
required air and creepage distances.
Cap：
Uncapped condition for CAT.II environment
Capped condition for CAT.III/ IV environments
The Cap shuld be firmly attached to the probes.
Protective fingerguard
Cap
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 10 —
5. Preparation for Testing
5-1 Removing the Cover
Model 3131A has a dedicated cover to protect against an impact from
the outside and prevent the operation part, and the connector socket
from becoming dirty.
Remove the cover and put it on the back side of the main body to make
measurements.
5-1-1 Method of removing the cover
5-1-2 Method of housing the cover
Fig.2
Fig.3
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 11 —
5-2 Mechanical Zero Adjustment
Check that the pointer lines up with the middle of the mark on the scale
correctly. If not, adjust it by rotating the meter movement zero adjust with
a screwdriver, etc.
5-3 Battery Voltage Check
①Set the range selector switch to BATT. CHECK position.
②Press the test button.
③Then the pointer deflects. Judge the battery status with BATT.GOOD
mark on the scale plate.
If the pointer does not move to BATT.GOOD mark, the batteries are
exhausted. Replace them with new batteries according to section 8 for
battery & fuse replacement.
5-4 Test Probe Connection
Insert the test probe fully into the terminal of the instrument.
Connect the earth clip of the test probe (black) to EARTH terminal and
the line probe (red) to LINE terminal of the connector terminal.
5-5 Test Probe Check
Set the range selector switch to x1Ωposition and press and turn the Test
button to lock it down. When the test probe are connected together, the
pointer should move from the ∞position towards the ０position on the
blue continuity scale. If not, the probe or fuse may be faulty. Release the
Test button after completion.
#CAUTION
Do not keep the test button pressed or locked by turning it clockwise during
battery check.
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 12 —
6-1 Disconnection and check of power source of circuit under test
#DANGER
●To avoid possible electrical shock, do not perform measurements on
energized (LIVE) circuits.
●Never make measurements with the battery compartment cover removed.
●Always Keep your fingers and hands behind the protective fingerguard on
test probe to avoid the possible shock hazard.
#CAUTION
●Never press the test button if the live circuit warning LED is lit or the
warning buzzer sounds. This may damage the circuit.
Voltage check can be made with the range selector switch at any position.
Be sure to turn off the breaker for the circuit under test.
①Connect the earth clip of the test probe (black) to the earth side and the line
probe (red) to the line side of the circuit under test.
②Ensure that the live circuit warning LED is not lit and the audible warning
is not present. If the LED is lit and the buzzer sounds, never press the test
button. Voltage is generated in the circuit under test. Recheck that the
breaker for the circuit under test is "OFF".
6. Operation
Fig.4
E L
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 13 —
6-2 Insulation Resistance Measurement
#DANGER
●Always test the circuit or equipment to ensure it is surely de-energized
before measurement according to the instruction of 6-1.
●
To avoid electrical shock, measurements must be performed on de-
energized circuits only.
●
When the test button is pressed with the range selector switch in the
insulation position, take care not to touch the tip of the test probe and the
circuit under test where a high voltage is present in order to avoid possible
shock hazard.
● Never make measurement with the battery compartment cover removed.
●Always Keep your fingers and hands behind the protective fingerguard on
test probe to avoid the possible shock hazard.
#CAUTION
●Never press the test button if the live circuit warning LED is lit or the
warning buzzer sounds. This may damage the circuit.
Conduct the voltage warning check before measurement to ensure that
the circuit under test is de-energized.
①Check the voltage which can be applied to the circuit under test and set
the range selector switch to the desired nominal output voltage range.
②Connect the earth clip of the test probe (black) to the earth terminal of the
circuit under test.
③Put the tip of the line probe (red) to the circuit under test and press the
test button.
④Read the scale directly for the 500V range, multiply by 0.5 for 250V and
by 2 for 1000V.
Fig.5 Insulation resistance measurement
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 14 —
6-3 Continuity Testing (Resistance Tests)
#DANGER
●Always test the circuit or equipment to ensure it is surely de-energized
before measurement according to the instruction of 6-1.
●To avoid electrical shock, measurements must be performed on de-
energized circuits only.
●
Never make measurement with the battery compartment cover removed.
●Always Keep your fingers and hands behind the protective fingerguard on
test probe to avoid the possible shock hazard.
#CAUTION
●Never press the test button if the live circuit warning LED is lit or the
warning buzzer sounds. This may damage the circuit.
Conduct the voltage warning check before measurement to ensure that
the circuit under test is de-energized.
●In case that an additional operating circuit is connected in parallel to the
circuit under measurement, the measurement error might be caused due
to the effects of impedance of the circuit conneted in parallel or transient
current.
#DANGER
Do not touch the circuit under test immediately after testing. Capacitance
stored in the circuit may cause electric shock.
Leave the test probe connected to the circuit and never touch the circuit until
the discharge is completed.
Principle of Insulation Resistance Measurement
Resistance value can be obtained by applying a certain high voltage to the
resistance (insulation resistance) and measuring the flowing current.
Resistance Value = Voltage/Current
RX = V/I
E
ARTH（＋）
LINE（－）
VOLTAGE:V RESISTANC
E
VALUE:RX
CURRENT:I
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 15 —
6-4 Continuous Measurement
A lock down feature is incorporated on the test button. Pressing and
turning it clockwise, lock the test button in the continuous operating
position.
To release the lock turn the test button counterclockwise.
#DANGER
Be extremely careful not to get electric shock during insulation resistance
measurement as high voltage is present on the tip of the test probe
continuously.
Principle of Continuity Testing (Resistance Test)
Resistance value can be obtained by applying a certain current to the
resistance under test and measuring the voltage generated on the both
sides of the resistance under test.
Resistance Value = Voltage/Current
RX = V/I
①Set the range selector switch to the desired position x 1Ωor x 10Ω.
②Short the line probe (red) and the earth clip of the test probe (black) and
press the test button. Adjust the ohm zero adjust to zero the pointer on
the scale.
③Connect the test probes to the circuit under test and press the test button.
④Read the scale directly for x 1Ωrange, multiply by 10 for x 10Ωrange.
Fig.6
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 16 —
7. Back Light Function
To facilitate working at night or dimly lit situations, a back light function is
provided which illuminates the display.
To operate this function, the back light button must be pressed and released
while pressing the test button. The back light continues illuminating for
approx. 40 seconds and then turn off automatically.
When the test button is released, the back light will turn off even within the
lighting time.
Fig.7 How to use the back light button
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 17 —
8. Battery & Fuse Replacement
8-1 Battery Replacement
①Disconnect the test probe from the instrument.
②Open the battery compartment cover by unscrewing the metal captive
screw to reveal battery compartment. Always replace all six batteries
with new ones at the same time.
Battery type: 6 x 1.5V battery type SUM-3, R6, AA or equivalent
8-2 Fuse Replacement
①Disconnect the test probe from the instrument.
②Open the battery compartment cover by unscrewing the metal captive
screw to reveal battery compartment and replace the fuse.
Fuse type: F500mA/600V fast acting ceramic fuse φ6.35 x 32mm
Install batteries in correct polarity as marked inside the case.
#DANGER
● Never open the battery compartment cover while making measurement.
To avoid possible electrical shock, disconnect the test probe before
opening the cover for battery and fuse replacement.
● Replacement fuse must have the following rating.
Fast acting type, F500mA/600V, φ6.35×32mm
Fig.8 How to replace batteries and fuse
SPARE FUSE
SCREW
FUSE
BATTERY
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]

— 18 —
9. Notes on Accessories
9-1 How to Fit Strap Belt and Test Probe Pouch
By hanging the instrument around the neck, both hands can be used
freely for easy and safety working.
①How to fit the strap belt
②Whole diagram when the test probe pouch is attached
Fig.9 How to fit the strap belt
Fig.10 How to fit the test probe pouch
www.GlobalTestSupply.com
Find Quality Products Online at: [e-mail]