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KEW 5020

KEW 5020
3 channel inputs for the simultaneous recording of Leakage Current , Load Current and Voltage
• Power Quality analysis
• Large capacity for storing 60,000 data points
• Lowpass Filter will filter out the harmonics
• LED flickers when the preset current/voltage value is exceeded
• CALL: Confirmation of recorded data
• Selection of One-time mode or Endless mode
• Non Volatile Memory
• Battery power indicator
• The userfriendly PC software "KEW LOG Soft 2" is supplied
• Continuous measuring time: Approx. 10 days (Alkaline Battery)

  • USB
  • External
Application Notes and Useful Tips

Insulation Level Monitoring by checking the leakage current

  • Detect an intermittent leakage current as often this is unpredictable.
  • Check for nuisance tripping of an RCD/ELCB due to a leakage current. Check also if RCD is tripping at its rated tripping current.
  • Check for the presence of harmonics. Use 2 clamp sensors (one per channel) on same line and use the filter function on one clamp sensor. A difference in values between the 2 channels will indicate the presence of harmonics. In this way the source generating harmonics can be traced.

Monitoring the load current

  • Confi rm the stability of a load (eg. motor) and the distortion it causes to the current by detecting accurately the over load caused for example by an inrush (starting) current and a surge current.
  • Check for phase imbalance (in a 3 phase system) 
  • Rate switchgear appropriately by measuring the peak current and the inrush current.
  • Analyze voltage drop due to starting current and thus compensate accordingly.

Monitoring voltage fluctuation (Power quality analysis)

  • Measure/ record the reference voltage, swell, dip, short interruption.
  • Locate the source of voltage drop caused by the operation of large motors in industrial applications.
    Eg. In the event of a voltage drop at the load side:
    1. If current remains stable, then the source will be upstream with respect to the load.
    2. If the current increases, then the source will be down stream with respect to the load.
  • Check out on machine (eg. welding robot, heavy mechanical electric machine) downtime/stoppages caused by abnormal voltage fl uctuations.

Monitoring overall electrical power of production line at factories or each floor at buildings

4 recording modes make various measurements possible
 Normal recording mode

For monitoring power line status or an intermittent leakage.

  • Records the variation of the current / voltage in a given interval (For monitoring the variation of the current / voltage against time.)
  • A choice of 15 recording intervals are available: 1 sec. to 60 min. 
    (1,2,5,10,15,20,30 sec, 1,2,5,10,15,20,30,60 min.)
  • The average of the measured value in every recording interval is recorded. The Max., Min. and Peak values (sampled crest value converted to sine RMS value) are recorded every 10 readings.

 Trigger recording mode

For observing an irregular operation of an ELCB/RCD, an irregular current / voltage.

  • Detects the value, time and frequency of the current / voltage when the preset value is exceeded.
  • When the detection level (i.e. preset value) is exceeded, 8 data points (True RMS values for approx. 0.8 sec) and peak value are recorded before and after the preset value is exceeded.
  • Inrush current or an abnormal current / voltage can be detected by sampling the inputs at every 1.6ms.
  • LED flickers when the measured values exceed the preset current / voltage value.

 Capture recording mode

For observing waveforms easily. 

  • Waveform display via a PC by sampling the inputs every 0.55ms.
  • When the preset current / voltage value is exceeded, instantaneous values are recorded for 200ms (from 10(50Hz) to 12 (60Hz) waveforms) before and after preset value is exceeded.
  • LED flickers when the measured values exceed the preset current / voltage value.

 Power Quality Analysis mode

For monitoring and observing voltage fluctuations.

  • Detects the reference voltage, Swell, Dip and Short Interruption. Records the values detected with the start time and end time.
  • Samples the inputs every 0.55ms and detects the voltage fl uctuation every 10ms.
  • LED fl ickers when the voltage fl uctuation is detected.

Large capacity for storing 60,000 data points

60,000 data points can be recorded when 1ch is used, and when all the three channels are used, 20,000 data points per channel can be recorded.

MAX.number of recorded data

Using all 3 channelsUsing 2 channelsUsing only 1 channel
20,000 data 30,000 data 60,000 data

Max. recording duration

Using all 3 channelsUsing 2 channelsUsing only 1 channel
1 sec. 5:33:20 8:20:00 16:40:00
2 sec. 11:06:40 16:40:00 1 day   9:20:00
5 sec. 1 day   3:46:40 1 day 17:40:00 3 days 11:20:00
10 sec. 2 days   7:33:20 3 days 11:20:00 6 days 22:40:00
15 sec. 3 days 11:20:00 5 days   5:00:00 10 days 10:00:00
20 sec. 4 days 15:06:40 6 days 22:40:00 13 days 21:20:00
30 sec. 6 days 22:40:00 10 days 10:00:00 20 days 20:00:00
1 min. 13 days 21:20:00 20 days 20:00:00 41 days 16:00:00
2 min. 27 days 18:40:00 41 days 16:00:00 83 days   8:00:00
5 min. 69 days 10:40:00 104 days   4:00:00 208 days   8:00:00
10 min. 138 days 21:20:00 208 days   8:00:00 416 days 16:00:00
15 min. 208 days   8:00:00 260 days 10:00:00 520 days   0:00:00
20 min. 277 days 18:40:00 416 days 16:00:00 833 days   8:00:00
30 min. 416 days 16:00:00 625 days   0:00:00 1250 days   0:00:00
60 min. 833 days   8:00:00 1250 days   8:00:00 2500 days   0:00:00

Continuous measuring time : Approx. 10 days (Alkaline Battery)
* Max recording time is dependent on battery life (approx 10-days with Alkaline battery)
Use of optional AC Adopter is recommended for long time recording.

LED flickers when the preset current / voltage value is exceeded.
  • Available for Trigger / Capture Recording, Power Quality Analysis modes.
  • LED on the Sensor connected channel blinks when following Trigger is detected.
  • LED flashes whenever the measured values exceed the pre-set detection level during measurements.
    Trigger is detected when the measured values exceed the pre-set detection level under Trigger / Capture Recording Mode and Power Quality Analysis Mode.
    For voltage values, Trigger is detected when it is below the detection level.

CALL : Confirmation of recorded data
  • The following can be displayed: number of recorded data points, (max+ min+ peak) value for each  channel complete with time/date information in the Normal recording mode. (Detected values (i.e. when values are outside preset limits) can be displayed in other recording modes)
  • RECALL: The last 10 recorded data points including time/date can be recalled on the logger display.

Selection of One-time mode or Endless mode

  • One-time on: 
    Recording will stop when memory is used up.

  • One-time off: 
    Over write the old data, and store the latest data.

Battery power indicator
  • Indicates battery voltage in 4-levels.
    (It is possible to use the logger for a further approx 24 hours even after the warning symbol is fl ashing.)

  • Recorded data will be retained even if the batteries are exhausted or replaced due to the presence of a nonvolatile memory (guaranteed for 10 years)
Analyzing and processing the recorded data with a PC

Easy to set up with a PC

  • Supplied with the user friendly software "KEW LOG Soft 2". 
  • The recorded data is downloadable onto a PC via USB cable.
  • Via the software the following parameters can be set: time/date, recording intervals, the start of recording, recording methods, name of monitoring site and comments.
  • The type of the sensor connected to the logger will be automatically recognized.
  • Just click appropriate dialog boxes for set up if it is not required to input any comments.
  • By using commercially available USB hub, multiple loggers can be connected to a PC and can set the synchronized time.

Large data can be easily processed

  • Recorded data can also be converted to CSV files, and data can be processed in Excel.

Graphical display

Simplified Power Integration

  • The PC software “KEW LOG Soft 2” provides easy calculation of integral power consumption.
    (Single-phase 2-wire, Single-phase 3-wire, Three-phase 3-wire, Threephase 4-wire)
    * Simplifi ed power integration function is available for the data recorded under Normal Recording mode.


【System requirements】

OS Windows® 11/10
Display XGA (1024x768 dots) or more
Hard-disk Space required 100Mbyte or more
Others With CD-ROM drive and USB port

Normal Recording Mode
(AC 50/60Hz, Sine wave, Input: 10% or more of the range at CH1)

RangeRMS Accuracy
100.0mA ±2.0%rdg±0.9%f.s.+ Accuracy of Sensor
Other ranges ±1.5%rdg±0.7%f.s.+ Accuracy of Sensor
Crest Factor 2.5 or less: RMS accuracy (sine) + 2%rdg + 1%f.s.

*Max, Min and Instant Peak values in Normal Recording mode are just reference values:
their accuracies aren't guaranteed.

Trigger Recording Mode (AC 50/60Hz sine wave)

100.0mA ±3.5%rdg±2.2%f.s.+ Accuracy of Sensor
Other ranges ±3.0%rdg±2.0%f.s.+ Accuracy of Sensor

Capture Recording Mode

100.0mA ±3.0%rdg±1.7%f.s.+ Accuracy of Sensor
Other ranges ±2.5%rdg±1.5%f.s.+ Accuracy of Sensor
Recording mode Normal, Trigger, Capture, Power Quality Analysis
Operating system Successive Approximation
(CH1 single synchronized sampling)
Rated max. working voltage AC 9.9Vrms, 14V peak value
Number of input channel 3ch
Measuring method True RMS
RMS measuring interval Approx. 100ms
Sampling interval Normal/Trigger mode : Approx. 1.65ms/CH
Capture mode : Approx. 0.55ms (waveform: at every 1.1ms)
P.Q.A mode : Approx. 0.55ms
Current range 8146 (30A type) : 100.0/1000mA/10.00/30.0A
8147 (70A type) : 100.0/1000mA/10.00/70.0A
8148 (100A type) : 100.0/1000mA/10.00/100.0A
8121 (100A type) : 10.00/100.0A
8122 (500A type) : 50.00/500.0A
8123 (1000A type) : 100.0/1000A
8128/8135 (5A type) : 5.000A/(50.00A)
8127 (100A type) : 10.00A/100.0A
8126 (200A type) : 20.00A/200.0A
8125 (500A type) : 50.00A/500.0A
8124 (1000A type) : 100.0A/1000A
8130 (1000A type) : 100.0/1000A
Voltage range 8309 (600V type) : 600.0V
Low battery warning Battery mark display (in 4 levels)
Over-range indication "OL" mark is displayed when exceeding the measuring range
Auto power off Turns off the instrument automatically if there is no switch operation for about 3 min.(This function doesn’t work during a recording.)
Possible measurement time Approx. 10 days (with alkaline LR6 batteries)
Applicable standards IEC 61010-1:2001 CAT III 300V Pollution degree2
IEC 61326 (EMC standard)
Dimension 111(L)×60(W)×42(D)mm
Weight Approx. 265g
Accessories 7148 (USB cable),
9118 (Carrying case),
Alkaline battery LR6×4pcs,
PC software "KEW LOG Soft 2",
Instruction manual, Quick manual, Install manual,
USB Notice sheet
Optional Accessories 8146/8147/8148 (Leakage & Load current Clamp Sensor),
8121/8122/8123 (Load current Clamp Sensor),
8124/8125(*1)/8126(*2)/8127(*3)/8128 (Load current Clamp Sensor),
8130(*4)/8135 (Flexible Clamp Sensor),
8309 (Voltage sensor)
7185 (Extension cable for sensor),
8320 (AC Adapter),
9135 (Carrying bag),

*1-4 Can use with after the following serial numbers.
 *1:8125 No.02637-
 *2:8126 No.00151-
 *3:8127 No.00181-
 *4:5020 No.8031560-

Accessories/Optional Accessories /Related Products

  • Product Catalogue
  • Instruction Manual
  • Applicable model list
  • Software

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