DCL31DR
DIGITAL CLAMP METER
INSTRUCTION MANUAL

2-2 Features• Safety design that complies with IEC61010-1 CAT. III 300 V• Compact pocket size
• AC/DC compatible clamp meter• DC+AC (True RMS) function• Auto power OFF (approx. 15 min.) (Disabling also possible)• Backlight
Measurement Category (Overvoltage Category)Equipment of CAT II :Primary cable runs of power-consuming equipment from a wall socket.
Equipment of CAT III :Primary cable runs of equipment directly connected to a distribution board
and cable runs from a distribution board to wall sockets.
Equipment of CAT IV :Cable runs from an incoming line to a distribution board.

[3] NAME OF COMPONENT UNITS
3-1 Main unit
Clamping current sensor(CT)

Dempa Bldg., 4-4 Sotokanda 2-Chome
Chiyoda-ku, Tokyo, Japan

Polarity
indicators

4-8 Peak hold: HOLD/PEAK button
When the HOLD/PEAK button is held depressed (for more than 1 sec.) during thevoltage or current measurement, the PEAK indicator lights on the display and thePeak Hold mode fixed at the 400.0 A range is started. Holding the button
depressed again cancels the Peak Hold mode. In the Peak Hold mode, the peakvalue of input waveform is held at intervals of 1 msec. The held value is updated
whenever a higher value is input but not updated at lower values. For instance,
when the input is a 100 A sine wave AC, the peak value is about 141 A ( 2 times
the rated value).
• Almost the same values are displayed with both the AC and DC functions.
• Peak Hold does not work with the negative (-) input with both the AC and DC
functions.
• When the HOLD/PEAK button is pressed in the Peak Hold mode, the PEAK andindicators light and the value displayed at that moment is held. Even
when the displayed value is held, the peak value continues to be updated
internally so, when the HOLD/PEAK button is pressed again to release the held
value, the latest updated peak value is displayed.
• The Peak Hold mode is canceled when the function switch is switched.

Examples of peak hold measurement:* The peak value of the negative (-) current is not held.

Center position indication

01-1507 2040 6011
Barrier[1] SAFETY PRECAUTIONSBefore use, read the following safety precautions
This instruction manual explains how to safely use your new DCL31DR digitalclamp meter. Before use, please read this manual thoroughly. After reading it,
keep it together with the product so you can refer to it when necessary. If thisproduct is not used as specified in this manual, its protection function may becompromised.
To avoid accidental burns or electric shock, always follow any instructions with
“ WARNING” or “ CAUTION” headings.

Measurement possible

DC current peakZERO button

Measurement possible

SELECT button
Power button
TriggerWARNING

1. Do not apply an input voltage exceeding the maximum rated current.
2. During measurement, do not hold the measurement clip at any point
beyond the barrier.

5-1 Start-up inspection
Perform the following pre-operational check for safety.
• Check the external appearance. Check that the main unit is free of abnormality
or damage due to dropping, etc.
• Check that the test leads are free of irregularity such as wire disconnection or
crack.
• Check that theindicator is not lit. If it is lit, replace the batteries with new ones.
• Make sure your hands and the instrument are not wet.
*If nothing is displayed on the LCD, the batteries might have been totally discharged.
5-2 Current measurements
CAUTION

1. To improve the measuring accuracy, position the conductor at the centerof the clamp sensor.
2. Always clamp only one wire at a time. Accurate measurement is impossible
if two or more wires, a cable with multiple conductors or a parallel cord isclamped.
3. Accurate measurement is impossible if the clamp sensor is not closed
completely.
4. Accurate measurement is sometimes impossible near a source of strong
magnetic field such as a transformer or high-current line, near a source ofelectromagnetic waves such as radio equipment or near a charged object.
5. The CT may generate an oscillating sound when a high current is applied.
This is not malfunction.
6. During measurement with the DC current (DCA) function, the reading mayvary by a few counts when the orientation (effect of the terrestrial magnetism)or the ambient temperature of this instrument is changed significantly.

Measurement impossible

Backlight button

1-1 Explanation of Warning Symbols
The meanings of the symbols used in this manual and on the product are
explained below.
: Very important instructions for safe use.
•Warning messages are intended to prevent accidents to operating
personnel such as burn and electric shock.
•Caution messages are intended to prevent damage to the instrument.
The meanings of the symbols used exclusively on the product are explained below.
: Symbol requesting reference to the instruction manual before use: Potential of connection to a power line in live status: Double in sulation or reinforced insulation: Power switch: Backlight

DC current peak

HOLD/PEAK button[5] MEASURING PROCEDURE

AC current peak

Measurement impossible
Measurement possible

AC current peak

LCD

* Perform measurements using the clamp sensor. Each press of the button
switches the measurement function in sequence of AC → DC → DC AC →AC → …

Measurement possible→

3-2 Display
PEAK measurement
mode

Data HOLD

Measurement impossible
DC+AC current peak
Measurement possible
Measurement impossible
DC+AC current peak
Measurement possible→

Correct ○Auto power OFF enabled
Zero setting indicator

WARNINGTo avoid physical injury such as burns or electric shock, be sure toobserve the following instructions when using this instrument.
1. This instrument is a digital clamp meter for low voltages. It should be
used on power lines with a voltage to ground of 300 Vrms or less.
2. Pay special attention when measuring voltages of AC 33 Vrms (46.7 Vpeak) or DC 70 V or more to avoid injury. Also use insulating protective
equipment as required.
3. Never use the instrument on power lines that exceed the maximum
rated input current (see 1-3).
4. Do not use the instrument if the main unit is damaged or broken.
5. Do not use the instrument with the case or battery compartment cover
removed.
6. Do not hold the measurement clip at any point beyond the barrier.
7. Before performing measurement, make sure that the function is properly set.
8. Do not use the instrument when it or your hand is wet.
9. Do not attempt to repair or modify the instrument except to replace thebatteries.
10. Be sure to check the instrument before each use and inspect it at least
once a year.
11. Always use the instrument indoors.
12. To avoid compromising the protection function of this instrument, do
not use it in any way other than instructed in this manual.
* Voltage to ground of 300 Vrms or less: When the Y-connection voltage is 415 V,
the voltage to ground is equal to 415 / 3 ≒ 240 V.

1-3 Overload Protection Input Values
Input

Max. rated input current

Max. overload protection input

Clamp sensor

AC/DC 420 A

AC/DC 450 A

Load

Low battery indication

1-2 Warning Instructions for Safe Use→

Unit (ampere)

Measurement impossible

DC (Direct current)

AC (Alternate current)

Measurement impossible

Polarity (-)
Numeric value & decimal point[4] DESCRIPTION OF FUNCTIONS
4-1 Power button:
buttonPress the button to switch the power ON and OFF.
4-2 Auto power OFF function
The instrument incorporates the auto power OFF function that turns the
instrument OFF in about 15 minutes after the last operation. This function canbutton. The
be disabled by switching the instrument ON while holding theindicator on the display panel is extinguished when the auto power OFF
functions is disabled.
4-3 Low battery indication
The
indicator lights on the display when the batteries have discharged
down to a supply voltage of about 2.3 V or less. Replace the batteries when
this indicator lights up.
4-4 Data hold: HOLD/PEAK button
Press thebutton shortly. The
indicator lights on the display andthe value displayed at that time is held and will not change even if themeasurement data varies. Pressing the button shortly again extinguishes theindicator and the measurement data is no longer held.
* The held data is cleared when the function is switched by pressing the
SELECT button.

[2] APPLICATIONS AND FEATURES

4-5 Function switching: SELECT button
Each press of this button switches the measurement function in sequence of
AC → DC → DC AC → AC → …

2-1 Applications
This instrument is an AC/DC clamp meter with RMS response that allows you
to measure the current range specified in IEC 61010-1 CAT. III 300 V. It is
suitable for measuring the current of low-voltage power lines and electricalappliances, etc.

4-6 Zero setting: ZERO button
When the ZERO button is pressed while the DC or DC+AC function is
selected, theindicator lights on the display and the current input value isdisplayed as zero. Pressing the ZERO button again cancels the zero setting.
* This button is disabled while the AC function is selected.

− 1 −

− 2 −

4-9 AC Detection method
This meter employs the root-mean-square value method and indicates themagnitude of AC as the same amount of work as DC. Root-mean-squarevalues of sinusoidal waves and such non-sinusoidal waves as square waves
and chopping waves can be measured by the true RMS (Root Mean Square)
circuit. (The input signal measurement value is used as the scale of the actual
input signal power. It is therefore measured as a more effective value than thevalue obtained by average detection.)
4-10 Crest factor
The CF (crest factor) indicates the peak value of a signal by dividing it by its
root-mean-square value. With most common waveforms such as sinusoidal
wave and chopping wave, the crest factor is low. With low duty cycle pulse
waveforms, the crest factor is high. For the voltages and crest factors fortypical waveforms, see the table below.
Input Waveform
Sinusoidal
wave

Vp

Square
wave

Vp

0

p

0

π

π

Chopping Vp
0
wave

Pulse

p

π

2π

2π

2π

Vp
0

τ

2π

Mean Average Crest
Form
0 to PEAK RootSquare Value Value
Factor Factor
Vp
Vavg
Vp/Vrms Vrms/Vavg
Vrms

Vp

Vp

2 Vp
－
√2
π
=0.707 Vp =0.637 Vp =1.414
Vp
－

2
√

Vp

Vp

1

Vp
－

Vp

Vp
－
√3
2
=0.577 Vp =0.5 Vp =1.732

Vp

τ
τ－・Vp －
・Vp
2π
2π

3
√

2π
－
τ

π
－
2√
2
=1.111

Clamping single conductor on the center of clamp sensor.

Incorrect ×

LoadThis manual emplys soy ink.

4-7 Backlight function:
buttonPress this button to light the backlight of the display. Pressing the button again
extinguishes the backlight. The backlight is also extinguished automatically inabout 10 seconds after it is lit.

1
2
－

3
√

=1.155

Clamping multiple conductors.

Force applied to the tip ofclamp sensor.

2π－τVoltages of Various Waveforms
− 3 −

− 4 −

5-2-1 Measuring the AC current (ACA measurement)
Function

Input

RangesAC0.01 ～ 400.0

60.00/400.0 A* The accuracy-guaranteed frequencies of this measurement are from 40 to
400 Hz.

① Press the SELECT button so that AC lights.
② Open the clamp sensor, position the wire to be measured and close theclamp sensor completely.
③ Read the displayed value.

5-2-3 Measuring the DC + AC current (DCA+ACA measurement)This function measures the RMS value of a total-wave/half-wave rectified waveform
or a DC wave on which AC wave is superimposed.
Function

Input

RangesDC AC

0.1 ～ 400.0

400.0 AWARNING

1. To avoid electric shock, do not remove the battery compartment coverwhile an input is applied to the clamp sensor or the instrument ismeasuring something.
2. Make sure that this instrument is set to OFF before proceeding to thebattery replacement.

① Press the SELECT button so that both DC and AC light.
② Wait until the display stabilizes, then press the ZERO button to perform the zerolights on the LCD display.)adjustment. (③ Open the clamp sensor, position the wire to be measured and close the clamp
sensor completely.
④ Read the displayed value.
* DCA+ACA is internally calculated as (DC)2 + (AC)2. The polarity of the DC
component is not displayed.
* Note the input frequencies and the crest factor.
Remark:In general, AC measurements use AC coupling.
If an AC signal includes DC offset, only the AC component is measured by
cutting the DC component.
A waveform having the amplitude on only one side, such as the full-wave
rectified wave, is regarded as an AC waveform with which the 0 position is
moved to the midpoint in terms of area.

Waveform measured
withAC coupling
AC結合での測定波形

DC+AC
直流+交流

Full-wave rectified
waveform
全波整流波形① Using a Phillips screwdriver, remove thef i x i n g s c re w ( x 1 ) f ro m t h e b a t t e r ycompartment cover.
② Remove the battery compartment cover.
③ Replace both of the batteries in thebattery holder with new ones byobserving the correct polarity.
④ Place the battery compartment coverand tighten the fixing screw in theoriginal position.

[7] AFTER-SALE SERVICE
7-1 Warranty and provision
Sanwa offers comprehensive warranty services to its end-users and to its
product resellers. Under Sanwa's general warranty policy, each instrument iswarranted to be free from defects in workmanship or material under normal use
for the period of one (1) year from the date of purchase.
This warranty policy is valid within the country of purchase only, and applied
only to the product purchased from Sanwa authorized agent or distributor.
Sanwa reserves the right to inspect all warranty claims to determine the extent
to which the warranty policy shall apply. This warranty shall not apply todisposables batteries, or any product or parts, which have been subject to oneof the following causes:
1. A failure due to improper handling or use that deviates from the instruction manual.
2. A failure due to inadequate repair or modification by people other than Sanwa
service personnel.
3. A failure due to causes not attributable to this product such as fire, flood andother natural disaster.
4. Non-operation due to a discharged battery.
5. A failure or damage due to transportation, relocation or dropping after thepurchase.
7-2 Repair
Customers are asked to provide the following information when requesting
services:

5-2-2 Measuring the DC current (DCA measurement)[6] MAINTENANCE

Function

Input

RangesDC± 0.01 ～ 400.0

60.00/400.0 A① Press the SELECT button so that DC lights.
② Wait until the display stabilizes, then press the ZERO button to perform thelights on the LCD display.)
zero adjustment. (③ Open the clamp sensor, position the wire to be measured and close the clamp
sensor completely.
④ Read the displayed value* Align the orientation of the arrow on the side of the clamp sensor with theorientation of the measured current. If they are not aligned, the displayedpolarity becomes – (negative).

WARNING

1. This section is very important for safety. Read and understand the following
instructions fully and maintain your instrument properly.
2. To maintain safety and accuracy, calibrate and inspect the instrument atleast every year.

6-1 Maintenance and Inspection
Before use, check the instrument to confirm that there is no abnormality and that
the CT can be opened and close smoothly. If anything is abnormal, do not use theinstrument and return it to your authorized Sanwa agent or distributor for repair.
6-2 Calibration
For more information, please contact Sanwa’s authorized agent / distributeservice provider, listed in our website. See section 7-3.
6-3 Cleaning and Storage
CAUTION

1. The panel and case are not resistant to volatile solvent and must not becleaned with thinner or alcohol. If the instrument gets dirty, wipe with a soft
cloth moistened with a small amount of water.
2. The panel and case are not resistant to heat. Do not place the instrument
near heat-generating devices (such as a soldering iron).
3. Do not store the instrument anywhere it may be subject to vibrations or
could fall.
4. When storing the instrument, avoid hot, cold or humid locations, locations
exposed to direct sunlight, or locations where condensation is anticipated.
5. When the instrument is not going to be used for an extended time, besure to remove the batteries.

6-4 Battery replacement• Batteries shipped with the instrument
The batteries loaded at the factory are monitor batteries, so their service life
may be shorter than that of brand-new batteries. Monitor batteries are a typeof battery used to check the functions and performance of a product.

1. Customer name, address, and contact information
2. Description of the problem
3. Description of the product configuration
4. Model Number
5. Product Serial Number
6. Proof of Date-of-Purchase
7. Where you purchased the productPlease contact Sanwa authorized agent / distributor / service provider, listed
in our website, in your country with above information. An instrument sent to
Sanwa / agent / distributor without above information will be returned to thecustomer.
Note:1) Prior to requesting repair, please check the following:
Capacity of the built-in battery, polarity of installation and discontinuity of thetest leads.
2) Repair during the warranty period:
The failed instrument will be repaired in accordance with the conditions
stipulated in 7-1 Warranty and provision.
3) Repair after the warranty period has expired:• If it is expected that servicing can restore the original functioning of the product,
we will service it for a price upon request of the user.
• The service charge or transport freight could sometimes become higher than the
product price. Please consult us before asking for servicing.
• The minimum retention period of the servicing performance parts of thisproduct is six (6) years after the discontinuation of production. This period isequal to the servicing available period. However, the retention period of a partmay be reduced if it becomes unavailable due to discontinuation of productionof the part manufacturer, etc.
4) Precautions when sending the product to be repaired:
To ensure the safety of the product during transportation, place the product ina box that is larger than the product 5 times or more in volume and fill cushion
materials fully and then clearly mark “Repair Product Enclosed” on the box
surface. The cost of sending and returning the product shall be borne by thecustomer.
7-3 SANWA web site
http://www.sanwa-meter.co.jp
E-mail: exp_sales@sanwa-meter.co.jp− 6 −6000 countSampling rate

Approx. 2 times / sec. Approx. 1 time/sec. with
DC+AC function

Overload display“OL” on the numeric display

Range selection

Auto range

Low battery indication

When the batteries are discharged down to 2.3 V
or less, theindicator lights on the display.

Current measurement
methodClamping current sensor (CT )aperture diameterMax. approx. dia. φ 25 mm

Operation
environment

Altitude max. 2000 m, indoor use, environmental
pollution degree II.

Operatingtemperature/humidity

Temperature 5 to 40 °C,
Relative humidity max. 80 % RH at 5-31 °C anddecreases linearly through 80 % RH to 50 % RH at
31-40 °C (without condensation)

Storage temperature/humidity-10 to 40°C: Max. 80 % RH (without condensation)
40 to 50°C: Max. 70 % RH (without condensation)(Remove the internal batteries when the instrument
is not to be used for long time.)

Temperature
coefficient

At below 18 °C or above 28 °C, multiply accuracy
by x 0.15 per 1 °C

Power supply“AAA”-size alkaline battery LR03 x 2Auto power OFF

Power OFF in approx. 15 min. after last operation

Power consumption /Battery life

Approx. 25 mA / Approx. 35 hours (backlight
extinguished)

Dimensions and mass

145 (H) x 54 (W ) x 31 (D) mm, approx. 120 g(including batteries)

Safety standards

IEC61010-1, IEC61010-2-030 CAT. III 300 V,
IEC61010-2-32

EMC directive

IEC61326-1

Accessories

Instruction manual, carrying pouch (C-DCL10)

8-2 Measuring ranges and accuracies
Accuracy-guaranteed temperature/humidity range: 23 ±5 °C, max. 80 % RH
(without condensation).
rdg: Reading.
dgt: digits (lowest digit)
Accuracy-guaranteed range: 1 % to 100 % of measurement range
Crest factor CF: Full-scale CF < 1.6, half scale CF < 3.2

ACA measurement RMS response, AC coupling (sine wave alternate current)
Range
60.00 A
400.0 A

Resolution
0.01 A
0.1 A

Accuracy: 50/60 Hz

Accuracy: 45-400 Hz±(2.0 %rdg + 5 dgt)±(3.0 %rdg + 10 dgt)

DCA measurement
Range
60.00 A
400.0 A

Resolution
0.01 A
0.1 A

Accuracy±（2.0 %rdg + 5 dgt）

Note: Accuracy after the zero point is set by pressing the ZERO button.
DCA+ACA measurement
Range

Resolution

400.0 A

0.1 A

Accuracy: 50/60 Hz

Accuracy: 45-400 Hz±（2.5 %rdg + 10 dgt） ±（3.5 %rdg + 15 dgt）

Note: Accuracy after the zero point is set by pressing the ZERO button. The
polarity of the DC component is not displayed. * DCA+ACA is internallycalculated as DC2 + AC2.
Peak hold
Range

Resolution

Accuracy

400.0 A

0.1 A±（3.0 %rdg + 10 dgt）

* With a waveform having a level of 4.0 A or more and width of 2 msec, or more.
Accuracy measurement method(Example) ACA measurement
Reading: 10.00 A
Range accuracy: 60.00 A range = ±(2 %rdg + 5 dgt)
Error: ±(10.00 A x 2.0 % + 0.01 A + 5) = ±0.25 A
True value: 10.00 A ±0.25 A (in the range from 9.75 to 10.25 A)* 3 dgt in the 60.00 A range is equivalent to 0.03 A.
* 3 dgt in the 300.00 A range is equivalent to 0.3 A.

[8] SPECIFICATIONS
8-1 General specifications− 5 −Display

Operation method

Δ- Σ method

AC detection method

True RMS method (AC coupling)− 7 −Specifications and external appearance of the product described above
may be revised or modified without prior notice.

− 8 −