Kyoritsu 4200/4202 Earth Clamp Tester

Safety Precautions

This instrument has been designed and manufactured according to IEC 61010 safety requirements. It is essential to read and understand these instructions before use to ensure safe operation and maintenance.

WARNING

• Read and understand this manual before operating the instrument.
• Keep the manual handy for quick reference.
• Use the instrument only for its intended applications.
• Follow all safety instructions provided in this manual. Failure to do so may result in personal injury, damage to the instrument, or damage to the equipment being tested.
• The symbol ! on the instrument indicates that the user should refer to the relevant sections in the manual for safe operation.

DANGER: Reserved for conditions or actions that could cause serious or fatal injuries.

WARNING: Reserved for conditions or actions that could cause serious or fatal injuries.

CAUTION: Reserved for conditions or actions that could cause injury or damage to the instrument.

The following symbols are used on the instrument:

• !: Refer to the manual for explanations.
• [Double Insulation Symbol]: The instrument is protected by double or reinforced insulation.
• [Clamp Symbol]: This instrument can clamp live conductors.
• AC: Indicates AC current.

General Precautions

DANGER

• Never measure circuits with a potential exceeding AC300V.
• Do not measure during thunderstorms. Stop measurement and disconnect the instrument.
• Do not attempt to measure in the presence of flammable gases, as this could cause sparks and lead to an explosion.
• The jaws are metal and not fully insulated. Be cautious of short circuits when testing equipment with exposed metal parts.
• Never use the instrument if its surface is wet.
• Do not exceed the maximum input value for any measurement range.
• Do not measure currents exceeding 30A, as the jaws may overheat, causing fire or deformation. If the LCD displays 'L' when clamping conductors over 30A, stop measurement immediately and disconnect the conductor.
• Never open the battery cover during measurement.
• When the jaws are worn down to the wear line, stop using the instrument.

WARNING

• Never attempt to measure if the instrument has structural anomalies, such as a broken casing or exposed metal parts.
• Do not install replacement parts or modify the instrument. Return it to the dealer for repair or recalibration.
• Do not change batteries if the instrument's surface is wet.
• Always turn off the instrument before opening the battery cover to change batteries.
• Keep fingers and hands behind the safety barrier.

CAUTION

• Always press the Function button and confirm the correct function is selected before measuring.
• Do not expose the instrument to direct sunlight, high temperatures, humidity, or dew.
• Always press the Power button to turn off the instrument after use. If not using for a long period, store it after removing the batteries.
• Clean the instrument with a damp cloth and neutral detergent. Do not use abrasive products or solvents.
• Avoid dropping the instrument, as the precision jaws may be damaged.
• Avoid touching foreign substances with the jaw tips.

Features

This instrument is a digital earth resistance clamp meter, also used for AC current measurement up to 30A.

• Wide measurement range (Auto-ranging): Earth Resistance Max. 1500Ω, Resolution min. 0.01Ω; AC Current Max. 30A, Resolution min. 1mA.
• Noise Check Function: Detects current that affects earth resistance measurements and displays it on the LCD.
• True RMS: Provides accurate AC current readings, even with distorted waveforms.
• Auto Power Off Function: Prevents the instrument from being left on, conserving battery life. The instrument automatically shuts off after approximately 10 minutes of inactivity.
• Data Hold Function: Freezes the measured value on the display. The 'H' symbol appears on the LCD.
• Alarm Function: Provides audible warnings when earth resistance is 10Ω or less. The ')))' symbol appears on the LCD.
• Backlight Function: Illuminates the LCD for use in dimly lit areas. The backlight turns off automatically after 1 minute.
• Memory Function: Allows saving and recalling measured results (up to 100 memory locations).
• Safety Standards Compliance: Designed to meet IEC61010-1 (CAT.IV 300V Pollution Degree 2) and IEC61010-2-032.
• Double or Reinforced Insulation: The instrument is protected by double or reinforced insulation.
• Bluetooth Communication Function (KEW 4202 only): Enables remote verification of measurements by connecting to KEW4202 and Android devices via Bluetooth using the 'KEW Smart' application.

Specifications

* Crest factor ≤ 2.5 for sinusoidal waveform.

System Operation:

• Earth Resistance: Constant voltage injection, current detection (approx. 2400Hz), Dual integration.
• AC Current: Successive approximation.

Display:

• Liquid crystal display with a maximum of 2099 counts.
• 'OL' is displayed when the input value exceeds the range limit.

Response Time: Approx. 2 seconds.

Sampling Frequency: Approx. 2 times per second.

Operating Environment:

• Altitude: 2000m or less, indoor/outdoor use.
• Temperature & Humidity: 23°C±5°C / Relative humidity 85% or less (non-condensing).

Storage Environment:

• Temperature: -20°C to 60°C / Relative humidity 85% or less (non-condensing).

Operating Temperature & Humidity: -10°C to 40°C / Relative humidity 85% or less (non-condensing).

Power Source: DC6V R6P (Manganese dry battery) x 4 pcs, or LR6P (Alkaline battery) x 4 pcs.

Current Consumption:

• Model 4200: Approx. 50mA (max. 100mA)
• Model 4202: Approx. 90mA (max. 140mA)

Measurement Time:

• Model 4200: Approx. 12 hours (with R6P), Approx. 24 hours (with LR6)
• Model 4202: Approx. 5 hours (with R6P), Approx. 21 hours (with LR6)

Auto Power Off: The unit turns off approximately 10 minutes after the last button operation.

Applicable Standards:

• IEC61010-1:2001 (CAT. IV 300V Pollution Degree 2)
• IEC61010-2-032:2002
• IEC61326:2000 (EMC standard)

Overload Protection: AC120A / 10 seconds

Withstand Voltage: AC5320Vrms / 5 seconds

Insulation Resistance: 50MΩ / 1000V (between jaw parts and casing, excluding the jaw)

Conductor Size: Max. 32mm diameter.

Dimensions: 246(L) x 120(W) x 54(D)mm

Weight: Approx. 780g (including batteries)

Accessories:

• Battery R6P: 4 pcs (for 4200)
• Battery LR6: 4 pcs (for 4202)
• Instruction Manual
• Operation check resistor (MODEL 8304): 1 pc
• Hard case (MODEL 9128): 1 pc

Supplementary Notes:

Effective Value (RMS): Most AC currents and voltages are expressed as RMS values. The RMS value is the square root of the mean of the squares of the AC current or voltage values. While conventional clamp meters use RMS scales, they are calibrated for sinusoidal waveforms based on the average value. The conversion factor of 1.111 is used for sinusoidal waves. These instruments may be inaccurate if the input voltage or current has a waveform other than sinusoidal.

CF (Crest Factor): Calculated by dividing the peak value by the effective value.

• Sinusoidal wave: CF=1.414
• Square wave with 1:9 duty cycle: CF=3

Instrument Description

Parts and Buttons:

1. Jaws
2. Trigger
3. Backlight Button: Activates/deactivates backlight.
4. Function Button: Switches between AC Current (ACA) and Earth Resistance functions.
5. Memory Mode Button: Checks measured values in memory.
6. Data Hold Button: Freezes the displayed value. Press again to release.
7. Power Button: Turns the instrument ON/OFF.
8. Display (LCD)
9. Cursor Button (UP): Selects memory address for saving or recalling values.
10. Cursor Button (DOWN): Selects memory address for saving or recalling values.
11. Guard Button: Saves the measured value.
12. Safety Barrier: Provides protection against electric shock and ensures minimum air gap and creepage distance.

LCD Symbols:

• MEM: Appears when saving a value or in memory mode.
• BATT: Indicates low battery.
• OPEN: Appears in Earth Resistance mode if the jaws are not properly closed.
• NOISE: Appears in Earth Resistance mode when current or noise affects the measurement.
• H: Indicates Data Hold function is active.
• AC: Indicates AC Current function is active.
• [Continuity Symbol]: Appears when continuity is detected in resistance measurement.

Measurement Principle

This instrument measures earth resistance in multi-earth systems. It considers the earth resistance to be checked (Rx) and other resistances (R1, R2, ... Rn) connected in parallel. The combined resistance of these parallel resistances (Rs) is considered very small compared to Rx.

The instrument applies voltage (V) to the circuit and measures current (I). Resistance (R) is calculated by detecting current with another jaw (CT2). This measured value R is approximately equal to Rx, as Rs is negligible.

CAUTION:

• This instrument does not support measurement in the following earth systems:
• Single earth systems not connected to other earths (e.g., lightning rods).
• Systems where AC current exceeds 2A.
• Earth resistance to be measured is lower than other earth resistances.
• Earth resistance exceeding 1500Ω.
• For precise measurements in single-earth systems, use the Kyoritsu Earth Resistance Meter models M4102A or M4105A.

Preparation for Measurement

CAUTION:

• The instrument self-calibrates for approximately 3 seconds upon power-on. Do not clamp any conductor or open the jaws during this period, as it may lead to inaccurate measurements.

1. Battery Voltage Check:

• When powering on, if the LCD is blank or the 'BATT' symbol appears, replace the batteries.

2. Earth Resistance Measurement Verification:

• Clamp the included operation check resistor (MODEL 8304) to verify correct operation.
• The indicated value should be within the acceptable ranges: 1Ω (0.79~1.21Ω), 10Ω (9.25~10.75Ω).
• If the indicated value significantly exceeds these ranges, contact Kyoritsu for service.

Measurement Methods

7.1 Normal Current Measurement

• Press the Function button (A/Ω) and select ACA mode.
• Ensure 'mA' is displayed and 'MEM' is not shown on the LCD.
• Open the jaws and clamp around a single conductor.
• The measured current is displayed on the LCD.

Correct vs. Incorrect Measurement:

• Correct: Clamp the conductor centrally within the jaws.
• Incorrect: Clamp the conductor off-center or with multiple conductors.

7.2 Balanced Leakage Current Measurement

• Press the Function button (A/Ω) and select ACA mode.
• Ensure 'mA' is displayed and 'MEM' is not shown on the LCD.
• Clamp all conductors except the earth wire.
• The measured current is displayed on the LCD.

Examples:

• Single-phase (2 wires): Clamp both conductors.
• Three-phase (3 wires): Clamp all 3 conductors (including neutral if present).
• Three-phase (4 wires): Clamp all 4 conductors (including neutral if present).

7.3 Earth Resistance Measurement

CAUTION:

• Before measuring earth resistance, measure the current flow in the earth wire using the 'Normal Current Measurement' method (Section 7.1).
• If 'NOISE' is displayed, it indicates potential errors. Reduce current flow by turning off the device under test.
• Measurement is not possible in single-earth systems or when the resistance to be measured is lower than other earth resistances.
• Avoid using multiple instruments on the same earth system to prevent inaccurate readings.
• The 'OPEN' symbol appears if the jaws are not properly closed. Measurement stops when this symbol is displayed. Close the jaws properly to resume measurement.
• The response time for Earth Resistance is approximately 7 seconds. Wait for stable readings.

Measurement Procedure:

• Press the Function button (A/Ω) and select Earth Resistance mode.
• Ensure 'Ω' is displayed and 'MEM' is not shown on the LCD.
• Open the jaws and clamp around the earth wire to be measured.
• The measured resistance value is displayed on the LCD.

Noise Check Function:

• The 'NOISE' indicator appears if the current flowing through the earth conductor exceeds:
• 20Ω / 1500Ω range: 2A or less
• 200Ω range: 400mA or less
• Harmonics in the earth conductor current can also affect measurements.

Jaw Verification Function:

• The 'OPEN' symbol indicates the jaws are not properly closed. Measurement will stop if this symbol is displayed.

Other Functions

8.1 Auto Power Off Function

This function conserves battery life by automatically turning off the instrument after approximately 10 minutes of inactivity. A beep sounds before shutdown. To disable this function: Turn on the instrument while holding the Data Hold button. Then release the Power button, but keep holding the Data Hold button. The display will show 'POFF' for 1 second. To re-enable, turn off the instrument without holding the Data Hold button.

8.2 Data Hold Function

Press the Data Hold button to freeze the displayed value. The 'H' symbol appears on the LCD. Press the button again to release the hold. Auto Power Off also deactivates Data Hold.

8.3 Alarm Function

Provides an audible alarm when earth resistance is 10Ω or less. To activate, press the Function button (A/Ω) for at least 2 seconds while in Earth Resistance mode. The ')))' symbol will appear. Press the Function button again to deactivate.

8.4 Backlight Function

Press the backlight button to turn on the LCD illumination. Press again to turn it off. The backlight automatically turns off after 1 minute.

8.5 Memory Function

Saving Measurements:

• Use the cursor buttons (▲/▼) to select a memory address (1-100) in ACA or Earth Resistance mode.
• Press the Guard button (MEM WRITE) to save the displayed value. The 'MEM' symbol appears briefly. The memory address automatically advances. Saved data overwrites existing data.

Recalling Stored Data:

• Press the Memory Mode button (MEM MODE) to enter memory mode. The 'MEM' symbol appears.
• Use the cursor buttons (▲/▼) to browse memory addresses and view stored values.
• Press the Memory Mode button or Function button (A/Ω) to exit memory mode. '----' indicates an empty memory address.

Clearing Stored Data:

• Clear a single measurement: Press and hold the Guard button (MEM WRITE) while pressing the MEM MODE button. 'clr' appears, and the selected memory data is cleared.
• Clear all data: With the instrument off, press and hold the MEM MODE and Guard buttons, then press and release the Power button. 'MEM', 'ALL', and 'clr' will appear briefly, indicating all data has been cleared.

8.6 Bluetooth Communication Function (KEW 4202 only)

The KEW 4202 can communicate data with Android devices via Bluetooth using the 'KEW Smart' application. This function is not available on the MODEL 4200. Download the 'KEW Smart' app from the internet.

Precautions for Bluetooth:

• Maximum Bluetooth communication distance is approximately 10m, but can be reduced by obstacles.
• Interference may occur with wireless LAN devices (IEEE802.11 B/g). Keep devices separate or turn off LAN devices.
• Establishing a connection may be difficult if the device is in a metal case.
• Kyoritsu is not responsible for data leaks during Bluetooth communication.
• If connection fails, try with other Android devices or contact your Kyoritsu dealer.
• Bluetooth SIG, Inc. owns the Bluetooth trademarks. Android and Google Maps are registered trademarks of Google Inc.

Preparing for Bluetooth Connection:

• Pair the Android device with the KEW 4202. Refer to the Android device's manual or the 'KEW Smart' app help.

Communication with Android Devices:

• Turn on KEW 4202 and select a measurement function.
• Open 'KEW Smart' on the Android device and select the KEW4202.
• Tap 'Start Measurement' to display results on the Android device.
• Tap 'Disconnect' to end communication. Tap 'Connect' to reconnect.
• Tap 'Stop Measurement' to stop measurement without disconnecting.

KEW Smart (KEW 4202) Features

Remote verification of measurements (earth resistance/current) is possible using the 'KEW Smart' Android application.

KEW Smart Features:

• Remote measurement verification.
• Data retention (save/display measurements with comments, including GPS location if enabled).
• Comparator function (compare measured values against preset values).
• Memory download: Download data from KEW 4202 by pressing the memory mode switch.

Internet Connection Features:

• Email: Send measured data via email.
• Map: View measured locations on Google Maps if GPS data is saved.

Precautions:

• KEW 4202 battery level is not displayed on Android devices. Ensure sufficient battery charge before use.
• Remote control of KEW 4202 functions (e.g., changing functions, data hold) from Android devices is not possible.

Battery Replacement

NOTICE:

• To avoid electric shock, disconnect the instrument from the circuit and turn it off before changing batteries.

CAUTION:

• Do not mix old and new batteries. Do not mix different battery types.
• Install batteries with correct polarity as indicated inside the compartment.
• When the 'BATT' symbol appears, replace the batteries. The LCD will be blank if batteries are completely depleted.

Procedure:

1. Disconnect the instrument if a measurement is in progress.
2. Turn off the instrument.
3. Remove the screw from the battery cover on the back of the unit and remove the cover.
4. Install new batteries (R6P or LR6P: 4 pcs each) with correct polarity.
5. Replace the battery cover and secure it with the screw.

Pairing with Bluetooth Compatible Devices (KEW 4202)

Pairing is necessary to connect KEW 4202 and Android devices via Bluetooth.

• If the 'BATT' symbol appears, replace batteries before pairing.
• Turn on KEW 4202.
• On the Android device, go to Settings > Wireless & networks > Bluetooth settings.
• Select 'Search for Bluetooth devices'. The model name 'KEW4202-XXXXXXX' (where XXXXXXX is the serial number) will appear.
• Select and pair the device.
• If pairing fails, check the distance between devices, ensure Bluetooth is enabled on the Android device, and try again. Network connection may affect pairing time.
• If the instrument malfunctions, return it to the dealer with a description of the fault. Include the operation check resistor (MODEL 8304) for repair.
• Before returning, ensure instructions were followed and batteries were checked. Provide detailed fault information for faster repair.