KYORITSU KEW 6310 User manual

INSTRUCTION MANUAL
POWER QUALITY ANALYZER
KEW 6310
KYORITSU ELECTRICAL INSTRUMENTS WORKS, LTD.
TOKYO, JAPAN

Contents KEW6310
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Contents ········································································································································1
Unpacking·······································································································································5
Safety warnings······························································································································7
Section 1 Instrument Overview···································································································· 1.1
1.1 Functional Overview······························································································· 1.1
1.2 Features·················································································································· 1.3
1.3 Connection Diagram ······························································································ 1.5
1.4 Measuring Procedure····························································································· 1.6
1.5 Outline of max demand measurement concept··················································· 1.7
Section 2 Instrument Layout········································································································· 2.1
2.1 Front View··············································································································· 2.1
2.2 Connector················································································································ 2.3
2.3 Side Face················································································································ 2.4
2.4 Battery Case··········································································································· 2.5
2.5 Marks displayed on the LCD·················································································· 2.6
Section 3 Getting started··············································································································· 3.1
3.1 Preparation·············································································································· 3.1
3.1.1 Putting Input terminal plate on the Input terminal··································································3.1
3.1.2 Attaching Markers to Voltage test leads and Clamp sensors··············································3.2
3.2 Power Supply·········································································································· 3.3
3.2.1 Battery········································································································································3.3
3.2.2 AC Power Supply·····················································································································3.9
3.3 Voltage test leads and Clamp sensor connection···············································3.10
3.4 Start KEW6310······································································································3.11
3.4.1 Start-up Screen··························································································3.11
3.4.2 Error message··························································································3.13
Section 4 Setting··························································································································· 4.1
4.1 List of Setting items································································································· 4.1
4.2 Settings····················································································································4.3
4.2.1 Basic Setting······························································································································4.3
4.2.2 Measurement Setting············································································································4.21
4.2.3 Save Setting···························································································································4.59
4.2.4 Other Setting··························································································································4.75
Section 5 Wiring Configurations··································································································· 5.1
5.1 Important preliminary checks·················································································· 5.1
5.2 Basic Wiring Configuration····················································································· 5.2
5.3 Wiring check············································································································ 5.7
5.3.1 Checking procedure·················································································································5.7
5.3.2 Criteria of Judgment·················································································································5.8
5.4 Using supplementary VT/CT’s ··············································································· 5.9

KEW6310 Contents
KEW6310 2
Section 6 Instantaneous value measurement············································································· 6.1
6.1 Indications on LCD·································································································· 6.1
6.1.1 Display screen..........................................................................................................................6.1
6.1.2 Switching displays....................................................................................................................6.8
6.1.3 Zoom..........................................................................................................................................6.9
6.2 Measuring Procedure····························································································6.11
6.3 Data saving············································································································6.12
6.3.1 Saving Inst measurement data····························································································6.12
6.3.2 Limitations of saving··············································································································6.14
6.3.3 Saved data·····························································································································6.15
6.4 Ranges and Over-range indications····································································6.18
6.4.1 Ranges···································································································································6.18
6.4.2 Over-range / Bar indication···································································································6.21
Section 7 Integration measurement····························································································· 7.1
7.1 Indications on LCD·································································································· 7.1
7.1.1 Display screen··························································································································7.1
7.1.2 Switching displays····················································································································7.2
7.1.3 W Range display······················································································································7.3
7.2 Measuring Procedure······························································································ 7.4
7.3 Data saving·············································································································· 7.5
7.3.1 Saving Integration measurement data···················································································7.5
7.3.2 Limitations of saving·················································································································7.7
7.3.3 Saved data································································································································7.7
7.4 Ranges and Over-range indications ······································································ 7.9
7.4.1 Ranges······································································································································7.9
7.4.2 Over-range / Bar indication······································································································7.9
Section 8 Demand measurement································································································ 8.1
8.1 Indications on LCD·································································································· 8.1
8.1.1 Display screen··························································································································8.1
8.1.2 Switching displays····················································································································8.5
8.1.3 W Range / Wh Range display································································································8.5
8.2 Measuring Procedure····························································································· 8.6
8.3 Data saving··············································································································8.7
8.3.1 Saving Demand measurement data······················································································8.8
8.3.2 Limitations of saving··············································································································8.10
8.3.3 Saved data·····························································································································8.10
8.4 Ranges and Over-range indications····································································8.12
8.4.1 Ranges···································································································································8.12
8.4.2 Over-range / Bar indication···································································································8.12
Section 9 WAVE Range················································································································ 9.1
9.1 Indications on LCD·································································································· 9.1
9.1.1 Display screen··························································································································9.1
9.1.2 Switching displays····················································································································9.3
9.1.3 Zooming/ downsizing ·············································································································9.5
9.2 Measuring Procedure····························································································· 9.6

Contents KEW6310
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9.3 Data saving·············································································································· 9.7
9.3.1 Saving Procedure·····················································································································9.7
9.3.2 Limitations of saving·················································································································9.9
9.3.3 Saved data································································································································9.9
9.4 Ranges and Over-range indications····································································9.12
9.4.1 Ranges···································································································································9.12
9.4.2 Over-range / Bar indication···································································································9.12
Section 10 HarmonicAnalysis····································································································10.1
10.1 Indications on LCD·····························································································10.1
10.1.1 Display screen·······················································································································10.1
10.1.2 Switching displays·················································································································10.4
10.1.3 Logarithm display··················································································································10.5
10.2 Measuring Procedure·························································································10.6
10.3 Data saving·········································································································10.7
10.3.1 Saving Procedure··················································································································10.7
10.3.2 Limitations of saving··············································································································10.9
10.3.3 Saved data·····························································································································10.9
Section 11 Power Quality·············································································································11.1
11.1 Display screen·····································································································11.2
11.2 Swell / Dip / Int measurement·············································································11.3
11.2.1 Display screen·················································································································· 11.3
11.2.2 Measuring Procedure······································································································11.4
11.2.3 Data saving······················································································································· 11.7
11.2.4 Limitations of saving········································································································· 11.9
11.2.5 Saved data························································································································ 11.9
11.3 Transient measurement····················································································11.11
11.3.1 Display screen················································································································11.11
11.3.2 Measuring Procedure····································································································11.12
11.3.3 Data saving·····················································································································11.14
11.3.4 Limitations of saving·······································································································11.16
11.3.5 Saved data ·····················································································································11.16
11.4 Inrush current measurement············································································ 11.19
11.4.1 Display screen················································································································11.19
11.4.2 Measuring Procedure····································································································11.20
11.4.3 Data saving·····················································································································11.22
11.4.4 Limitations of saving·······································································································11.24
11.4.5 Saved data ·····················································································································11.24
11.5 Unbalance rate measurement········································································· 11.27
11.5.1 Display screen······················································································· 11.27
11.5.2 Measuring Procedure···································································································11.28
11.5.3 Data saving····················································································································11.29
11.5.4 Limitations of saving······································································································11.31
11.5.5 Saved data·····················································································································11.31

KEW6310 Contents
KEW6310 4
11.6 Flicker······················································································································11.33
11.6.1 Display screen·····················································································································11.33
11.6.2 Measuring Procedure·········································································································11.37
11.6.3 Data saving··························································································································11.38
11.6.4 Limitations of saving············································································································11.40
11.6.5 Saved data···························································································································11.40
11.7 Capacitance Calculation- Sizing of capacitor banks for Power factor correction
(PFC) ·································································································································11.43
11.7.1 Display screen·····················································································································11.43
11.7.2 Measuring Procedure·········································································································11.45
11.7.3 Data saving··························································································································11.46
11.7.4 Limitations of saving············································································································11.48
11.7.5 Saved data···························································································································11.48
Section 12 CF card/ Internal memory····························································································· 12.1
12.1 Instrument and CF card / Internal memory ·························································· 12.1
12.2 Placing / removing the CF card············································································· 12.4
12.3 CF card and Internal memory················································································ 12.6
12.4 Backup memory······································································································12.9
Section 13 Communication function/ Interface software······························································ 13.1
13.1 Software Installation (KEW PQAMASTER)························································ 13.2
13.2 USB driver installation····························································································· 13.4
13.3 Starting “KEW PQAMASTER”·············································································· 13.6
13.4 USB driver un-installation······················································································· 13.7
Section 14 Other functions··············································································································· 14.1
14.1 Input/ Output terminals···························································································· 14.1
14.2 Getting power from measured lines······································································ 14.2
14.3 Auto-ranging············································································································ 14.4
14.4 Operation atAC power interruption·······································································14.4
Section 15 Troubleshooting············································································································· 15.1
15.1 General troubleshooting························································································· 15.1
15.2 Error messages and actions·················································································· 15.2
Section 16 Specification··················································································································· 16.1
16.1 General specification ······························································································ 16.1
16.2 Inst measurement··································································································· 16.2
16.3 Integration measurement·······················································································16.4
16.4 Demand measurement·························································································· 16.6
16.5 Waveform measurement······················································································· 16.6
16.6 Harmonic measurement ························································································ 16.6
16.7 Power quality··········································································································· 16.7
16.7.1 Swell/ Dip/ Int measurement································································································16.7
16.7.2 Transient measurement········································································································16.7
16.7.3 Inrush currentmeasurement································································································16.7
16.7.4 Unbalance rate measurement·····························································································16.7
16.7.5 Capacitancecalculation········································································································16.8
16.8 Other specifications································································································· 16.8
16.9 Specification of Clamp sensor ·············································································16.11

Unpacking Procedure KEW6310
5 KEW6310
●Unpacking Procedure
We thank you for purchasing the Power Quality Analyzer “KEW6310”. Please check the contents and
instrument before use.
●Items listed below are included with the standard set:
1 Main unit KEW6310 : 1 unit
2 Voltage test lead MODEL7141 : 1 set
(red, black, green, blue: 1pce for each)
3 Power cord MODEL7170 : 1 pce
4 USB cord MODEL7148 : 1 pce
5 Quick manual 1 pce
6 CD-ROM 1 pce
7 Battery Alkaline size AA battery LR6: 6pcs
8 Compact flash card 1 pce
9 Carrying case MODEL9125 : 1 pce
10 Input terminal plate 1 pce
11 Cable marker 8-color x 4pcs each (red, blue, yellow,
green, brown, gray, black, white)
12 Card Reader MODEL8319
Optional parts
13 Clamp sensor Depending on model purchased
14 Instruction manual for
clamp sensor 1 pce
15 Compact flash card 64M/ 128M/ 256M/ 1GB
16 Carrying case for Main unit
(with magnet) MODEL9132
17 Power supply adapter MODEL8312
1. Main unit 2. Voltage test lead 3. Power cord 5. Quick manual 6. CD-ROM
4. USB cord
7. Battery 8. Compact flash card 9. Carrying case 11. Cable marker
10. Input terminal plate 12. Card Reader : M-8319

KEW6310 Unpacking Procedure
KEW6310 6
13. Clamp sensor 14. Instruction manual for clamp sensor
(depending on model purchased)
50AType(φ24mm) M-8128
15. Compact flash card
100AType(φ24mm) M-8127 32MB M-8305
200AType(φ40mm) M-8126 64MB M-8306
500AType(φ40mm) M-8125 128MB M-8307
1000AType(φ68mm) M-8124 256MB M-8322
3000AType(φ150mm) M-8129
1GB M-8323
10AType(φ24mm) M-8146
10AType(φ40mm) M-8147
10AType(φ68mm) M-8148
1AType(φ24mm) M-8141
1AType(φ40mm) M-8142
1AType(φ68mm) M-8143
●Storage
Store the items as shown below after use. 16. Carrying case for Main unit 17. Power supply adapter
(with magnet)
●In case any of the items listed above are found to be damaged or missing or if the
printing is unclear, please contact your local KYORITSU distributor from where the
instrument was purchased.

Safetywarnings KEW6310
7 KEW6310
●Safety warnings
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 passing quality control tests.
This instruction manual contains warnings and safety rules which have to be observed by the user
to ensure safe operation of the instrument and to maintain 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.
●Read the enclosed Quick manual after reading this instruction manual.
●As to the Clamp sensor use, refer to the instruction manual supplied with the sensor.
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.
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.
This instrument meets CAT. III 600V. To ensure safe operation of measuring instruments, IEC 61010 establishes
safety standards for various electrical environments, categorized as CAT.I 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.
CAT.I: Secondary electrical circuits connected to an AC electrical outlet through a transformer or similar device.
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).

KEW6310 Safety warnings
KEW6310 8
DANGER
●Verify proper operation on a known source before use.
●Verify proper operation on a known source before use or taking action as a result of the indication of the
instrument.
●Never make measurement on a circuit in which the electrical potential exceeds AC600V.
●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.
●Never attempt to use the instrument if its surface or your hand are wet.
- Measurement -
●Do not exceed the maximum allowable input of any measuring range.
●Never open the Battery cover and CF card connector cover during a measurement.
- Battery -
●Never open the Battery Cover during a measurement.
●Brand and type of the batteries to be used should be harmonized.
- Power cord -
●Connect the Power cord mains plug to a mains socket outlet
●Use only the Power cord supplied with this instrument.
- Power supply connector -
●Never touch the Power supply connector although it is insulated while the instrument is operating with
batteries.
- Voltage test leads -
●Use only the ones supplied with this instrument.
●Confirm that the measured voltage rating of the test lead is not exceeded.
●Do not connect a Voltage test lead unless required for measuring the parameters desired.
●Connect Voltage test leads to the instrument first, and only then connect them to the circuit under
test.
●Never disconnect Voltage test leads while the instrument is in use.
●Connect to the downstream side of a circuit breaker since a current capacity at the upstream side is large.
●Do not touch two lines under test with the metal tips of the test leads.
●Never touch the metal tips of the test leads.
- Clamp sensor -
●Use only the ones dedicated for this instrument.
●Confirm that the measured voltage rating of the test lead is not exceeded.
●Do not connect a Camp sensor unless required for measuring the parameters desired.
●Connect sensors to the instrument first, and only then connect them to the circuit under test.
●Never disconnect sensors while the instrument is in use.
●Connect to the downstream side of a circuit breaker since a current capacity at the upstream side is large.
●Do not touch two lines under test with the metal tips of the test leads.

Safetywarnings KEW6310
9 KEW6310
WARNING
- Connection -
●Confirm that the instrument is off, and then connect the Power cord.
●Connect the Voltage test leads and clamp sensors to the instrument first. Cord to be firmly inserted.
●Never attempt to make any measurement if any abnormal conditions, such as a broken cover or
exposed metal parts are present on the Instrument, Voltage test leads, Power cord and Clamp sensor.
- Measurement –
●Ensure that the Current input terminal cover, USB connector cover and CF card connector cover are
closed when not in use during a measurement.
- Not in use for a long period -
●Remove the Power cord from the outlet if the instrument will not be in use for a long period.
- Repair -
●Do not install substitute parts or make any modification to the instrument. Return the instrument to your
local KYORITSU distributor for repair or re-calibration in case of suspected faulty operation.
- Battery -
●Do not try to replace the batteries if the surface of the instrument is wet.
●Ensure that the Power cord, Voltage test leads and Clamp sensor are removed from the instrument,
and that the instrument is switched off when opening the Battery cover for battery replacement.
●Do not use dry-cell batteries with the Selector Switch set to “RECHARGEABLE BATTERY” position.
It may cause electrical shock accident.
●Never mix new and old batteries.
●Install batteries in correct polarity as marked inside.
- Power cord -
●Do not use the damaged cord.
●Don’t put heavy things on, step on or pinch the cord, moreover, not to touch any heating material.
●When unplugging the cord from the mains socket outlet, do so by removing the plug first and not by
pulling the Power cord.
- Measures against abnormal symptoms -
●If the instrument begins to emit smoke, becomes too hot, or gives off an unusual smell, immediately
power it off and disconnect the power cord from the outlet. Also power off the power to the object under
test. If any anomalies as noted, contact your local KYORITSU distributor.
- Use of protective gears -
●Use insulated gloves, boots or head gears at measurements to ensure user’s safety.

KEW6310 Safety warnings
KEW6310 10
CAUTION
●Caution should be taken since conductors under test may be hot.
●Never apply currents or voltages exceeding the maximum allowable input for the instrument for a long time.
●Don’t apply currents or voltages to Voltage test leads or Clamp sensors while the instrument is in off status.
●Don’t use the instrument at dusty places or to be spattered.
●Don’t use the instrument under a strong electric storm or in the vicinity of energized object.
●Never give strong vibrations or drop shocks.
●Do not place or remove a CF card while CF card is being accessed. ( flashes while CF card is being
accessed.) Otherwise saved data in the card or the instrument may be damaged.
- Clamp sensor -
●Do not bend or pull the cable of the Clamp sensor.
- Treatment after use -
●Power off the instrument and disconnect the Power cord, Voltage test leads and Clamp sensors from
the instrument.
●Remove the batteries if the instrument is to be stored and will not be in use for a long period.
●Remove the CF card when carrying the instrument.
●Never give strong vibrations or drop shocks when carrying the instrument.
●Do not expose the instrument to direct sunlight, high temperatures, humidity or dew.
●Use a damp cloth with neutral detergent for cleaning the instrument. Do not use abrasives or solvents.
●Do not store the instrument if it is wet.
Carefully read and follow the instructions: DANGER, WARNING,CAUTION and NOTE( )
described in each section.
The following symbols are used in this manual:
User must refer to the explanations in the instruction manual.
Instrument with double or reinforced insulation, Class II insulation
~ AC
(Functional) Earth terminal

1.1 Functional Overview KEW6310
1.1 KEW6310
1. Instrument Overview
1. 1 Functional Overview
Instantaneous value measurement
Measures average/max/min values of instantaneous
values of current, voltage and electric power.
See Section 6 “Instantaneous value measurement”
for further details.
Integration value measurement
Measures active/ apparent/ reactive powers on
each CH.
See Section 7 “Integration value measurement”
for further details.
Demand measurement
Measures demand values based on the preset target
values. Digital output signals alert the user that the
predicted value may exceed a target value.
See Section 8 “DEMAND Measurement” for further
details.
SET UP
Setting of KEW6310 or for measurements
See “Setting (Section 4)” for further details.

KEW6310 1.1 Functional Overview
KEW6310 1.2
Measurement at WAVE Range
Displays vector / waveform of voltages and currents per CH
See “WAVE Range (Section 9)” for further details.
Harmonic measurement
Measures / analyzes harmonic components of current &
voltages
See “Harmonic Analysis (Section 10)” for further
details.
Power quality analysis
Measures swell, dip, int, transient, inrush current,
unbalance ratio and flicker, and also simulates power
factor correction with capacitor banks.
* Flicker measurement function is only available with ver.2.00 or
later.
See “Power Quality (Section 11)” for further details.

1.2 Features KEW6310
1.3 KEW6310
1.2 Features
This is a Power Quality Analyzer that can be used for various wiring systems. It can be used for
simple measurements of instantaneous/ integration/ demand values, and also for monitoring
waveforms and vectors, analyzing harmonics and measuring the fluctuations in supply voltages and
can perform Capacitance Calculation. Data can be saved either in the internal memory or a CF card,
and can be transferred to a PC either via a USB lead or a CF Card reader.
Safety Construction
Designed to meet the international safety standard IEC 61010-1 CAT.III 600V/ CATII. 1000V
Wiring configuration
KEW6310 supports : Single-phase 2-wire, Single-phase 3-wire, Three-phase 3-wire, Three-phase 4-wire.
Measurement and caluclation
KEW6310 measures voltage (RMS), current (RMS), and calculates active/reactive/apparent power, power factor,
phase angle, frequency, neutral current and active/ reactive/ apparent electric energy. (RMS)
Demand measurment
Electricity consumption can be easily monitored so as not to exceed the target maximum demand values.
Waveform / Vector display
Voltage and current can be displayed by waveform or vector.
Harmonic analysis
Harmonic components of voltage and current can be measured and analyzed.
Power quality analysis
Measuring Swell/ Dip/ Int, Transient, Inrush current, Unbalance ratio and flicker*, moreover, simulating power
factor correction with capacitor banks.
* Flicker measurement function is only available with ver.2.00 or later.

KEW6310 1.2 Features
KEW6310 1.4
Saving data
KEW6310 is endowed with a logging function with a preset recording interval. Data can be saved by manual
operation or at pre-set time & date. Screen data can be saved by using Print Screen function.
Dual power supply system
KEW6310 operates either withAC power supply or with batteries. Both dry-cell batteries (alkaline) and
rechargeable batteries (Ni-MH) can be used. In the event of interruption, while operating with AC power supply,
power to the instrument is automatically restored by the batteries in the instrument.
Large display
Color display with large screen
Light & compact design
Clamp sensor type, compact and light weight design
Application
Data in the internal memory or CF card can be transferred to a PC via a USB lead or a CF Card reader.As well
supplied software facilitates setting, optional analysis software facilitates data analysis.
Input/output function
Analogue signals from thermometers or light sensors can be measured simultaneously with electrical power
data via 2 analogue inputs (DC voltage); signals exceeding preset threshold values at each range can be
transmitted to alarm devices via 1 digital output (DC voltage)

1.3 Connection Diagram KEW6310
1.5 KEW6310
1.3 Connection Diagram
Voltage Input Power Cord
USB
Digital Output (1ch)
Analogue Input (2ch)
CF Card
Recorder / Alarm device
Thermometer/Light sensor
PC
Alkaline dry-cell / Ni-MH
rechargeable batteries
Current Input

KEW6310 1.4 Measuring Procedure
KEW6310 1.6
1.4 Measuring Procedure
●Steps for measurement
Ensuring your safety
See “Safety Warnings”.
Preparation
See “Section 3: Getting started”.
Basic / Measurement / Save Settings
See “Section 4: Setting”.
Wiring
See “Section 5: Wiring”.
* Measuring instantaneous values :
“Section 6: Instantaneous value Measurement”
* Measuring integration values:
“Section 7: Integration value Measurement”
* Measuring demand values:
“Section 8: Demand Measurement”
* Measuring vectors and waveforms:
“Section 9: WAVE Range”
* Analyzing Harmonics:
“Section 10: Harmonic Analysis”
* Measuring Power Quality:
“Section 11: Power Quality”

1.5 Outline of max demand measurement concept KEW6310
1.7 KEW6310
1.5 Outline of max demand measurement concept
In some countries, large consumers of electricity will usually have a maximum demand contract with the power
company. Such contract varies from country to country. The following is an explanation of a typical Japanese
maximum demand contract.
●Maximum Demand contract
In such a contract the electricity tariff rates (i.e. for kWhr units) are based upon the consumer’s maximum
power demand. The maximum demand is the maximum of average powers recorded over a 30min intervals.
This is measured by the maximum demand meter belonging to the power company. Let’s assume that a power
company has the following applicable rates.
$2 per KWhr unit for a recorded max demand 300KW during a year
$4 per KWhr unit for a recorded max demand 500KW during a year
$5 per KWhr unit for a recorded max demand 600KW during a year
Assuming that the consumer is on the 500kW/year rate (ie. $4), and the recorded max demand during a
particular day(say 15th January) is 600kW . Then the new applicable rate from 1st February onwards will be the
600kW/year rate (ie. $5) for the next 365 days. If a year later, on February 1st the recorded maximum demand
is 300kW, then the new applicable rates will be changed to 300kW/year rate (i.e. $2) for the subsequent 365
days. However if during this period, the max demand goes up again, and say 600kW is recorded on 15th March,
the applicable rates change again to the 600kW/year rate (i.e.$5) for the subsequent 365 days.
●Benefits of maximum demand control
It is thus important for consumers with such contracts to monitor closely fluctuations in their power demand to
ensure that their max demand limits are not exceeded and thus incur higher tariffs. Maximum Demand control is
more effective in countries with higher electricity tariffs.
●Status of maximum demand contract
In the past, in Japan, only consumers whose electricity supply was rated at 600kW or more used to enter into a
demand contract. However, nowadays power companies install maximum demand meters at all consumers
whose supply is rated 70kW or more.
●Maximum Demand measurement limitations
N.B. The readings from power company maximum demand meter and from the 6300 will not match completely
due to an obvious time-lag difference in the start of the integration period (eg.30mins) over which the max
demand is taken.

KEW6310 1.5 Outline of max demand measurement concept
KEW6310 1.8

2.1 Front View KEW6310
2.1 KEW6310
Display (LCD)
Keys
LED status indicator
Green lights up : Recording & measuring
Green flashes : Stand-by (lights up when preset time comes)
Red flashes : Charging batteries
2. Instrument Layout
2.1Front View
Display (LCD) / Keys