MULTI MEASURING INSTRUMENTS 340 User manual

AC CURRENT
MINI DIGITAL CLAMP-ON TESTER
MODEL 340
INSTRUCTION MANUAL
Thank you very much for selecting our digital AC clamp-on tester.
This model is complex instrument and employ a very reliable
mechanical/electronic design.
Before you use your new instrument, read this Instruction Manual completely and
familiarize yourself thoroughly with all functions. With proper use and care, your
tester will give you years of satisfactory service.
MULTI MEASURING INSTRUMENTS CO.,LTD.
Akihabara Murai Bldg. 7F, 1-26 Kanda Sakuma-cho,
Chiyoda-ku, Tokyo 101-0025 JAPAN
TEL: [phone] FAX: [phone]
Home Page: http://www.multimic.com/
E-mail: [email protected]

1. FEATURES
●This tester is a clamp-on type leakage ammeter which represents the latest in current transducer
and digital technology and is the world’s smallest and most accurate clamp-on type instrument of its
type.
●Compact and lightweight.
●This tester is least affected by the external magnetic field.
2. CAUTION
●Before operating this instrument, familiarize yourself with all instructions outlined in this manual.
●Always check to make sure that the function switch is set to the proper position.
●When making measurements, use CAUTION as dangerous voltages may be present in
normally safe areas.
●To avoid electrical shock, use CAUTION when working above 60V DC or 25VAC rms.
Such voltages pose a shock hazard.
●Never make measurements with the battery cover OFF.
●Never fail to keep the maximum tolerable input.
●Never operate this instrument if it becomes wet, damp or has any liquid
condensation build-up on any part of the instrument.
●Never make measurements for uninsulated conductors or bus bars.
3. SPECIFICATION
Measuring Method:
Dual integration mode
Display:
3.5 digit LCD max. reading of 1999
Range:
0~2mA/20mA/60A(50 or 60 Hz)
Accuracy:
23℃±5℃, 80%RH or less
Range
Resolution
Accuracy
2mA
0.1μA
±1.0%rdg ±5dgt(50/60Hz)
20mA
10μA
60A
0.1A
0~50A±1.0%rdg±5dgt
50A~60A-5.0%rdg±5dgt
Jaw opening capability:
35mmφ
Over range indication:
Blanking of all digits except MSD1
Maximum indication:
1999
Low battery indication:
"B" mark on LCD
Data hold indication:
"DH" mark on LCD
Sampling time:
2 times/sec
Limitation of Circuit Voltage:
Less than AC 600V
Withstanding Voltage:
AC 2000V (between the core of CT and outer case)
Operating temperature:
0℃to +40℃, ＜80%RH
Storage temperature:
-10℃to +60℃, ＜70% RH
Power supply:
SR-44 (1.55V)x2 or LR-44x2
Power consumption:
7mW
Battery life:
SR-44(100 hours)
LR-44(50 hours)
Size:
68.5(W)x175(H)x23(D)mm
Weight:
Approx. 145 g.
Accessories:
Soft case……………………….….1
Instruction manual……………..…1
Batteries, LR-44 (1.55V)…………2

4. DIMENSIONS AND PANEL FUNCTION
①Current transducer(Jaw)
⑤Wrist strap
②Jaw opening lever
⑥Range selector switch
③Data hold switch
⑦Power switch
④LCD display
⑧Battery cover
5. METHOD OF MEASUREMENT
5-1. Preparation and Caution before Measurement
●Before making measurements, install the batteries. Two LR-44 batteries can be used.
●Avoid using the tester in places subject to high temperatures, humidity or excessive vibration.
●Before measurements, be sure the data hold switch is set to "OFF". (It is impossible to make
measurements if the data hold switch is set to "ON".)
●Remove the battery if the tester will not be used for a long period of time.
5-2. Measurement of Leakage Current
5-2-1 . Leakage current measurement for the grounded conductor
1) Set the power switch to "ON" position.
2) Set the range selector switch to a range appropriate to the current to be measured.
3) Clamp the conductor of the circuit under test with the current transducer.
4) If you make measurements in a dark place or in a place where it is difficult to see the readings,
use the data hold switch.
5-2-2. Leakage current measurement for the single-phase or three-phase electric
circuit.
1) Set the power switch to "ON" position.
2) Set the range selector switch to a range appropriate to the current to be measured.
3) To measure a leakage current in a single-phase electric circuit, clamp the two conductors together.
Or clamp the three conductors together in the case of the three-phase electric circuit.
4) If you make measurements in a dark place or in a place where it is difficult to see the readings,
use the data hold switch.
5-3. Measurement of Line Current
1) Set the power switch to "ON" position.
2) Set the range selector switch to a range appropriate to the current to be measured.
3) Clamp the conductor of the circuit under test.
4) If you make measurements in a dark place or in a place where it is difficult to see the readings,
use the data hold switch.
Note: Clamp around only one conductor of the circuit to be measured.
APPENDIX:
When making the power switch on and off several times quickly for the short period, the display may
show “O.L”according to circumstances.
Make switching power on/off with the interval more than 2 sec.

CAUTION:
This tester is designed for low voltage applications.
To avoid electrical shock or damage, the measurement is limited to the
circuit under 600V AC and 60A AC.
Never make measurements for uninsulated conductors or bus bars.
6. REPLACEMENT OF BATTERIES
When the battery becomes exhausted or drops below the operating voltage, the "B"
mark is displayed. Turn the power switch to "OFF", prior to installing batteries.
To install the batteries, remove the battery cover located on the unit back.(See Fig.2)
Insert the two LR-44 or SR-44 into the battery case making sure that proper
polarity is observed. (See Fig.3)
Always replace both batteries at the same time. If the difference between the
voltages of the batteries is big, the measurement error may be caused.
4. REPAIR SERVICE
When requesting for repair service, please bring the instrument directly to the dealer where you bought.
When mailing the instrument, always pack it in its original or equivalent packing materials to avoid any
damage during the transportation and also put together with documents showing your name, address,
phone number and defect point.
5. WARRANTY
This instrument is sent out from our factory after the sufficient internal inspections but if you find any
defect due to the fault in our workmanship or the original parts, please contact the dealer where you
bought the instrument.
The warranty period is 12 months from the date of purchase and the instrument shall be repaired at free of
charge, provided that we judge the cause of defect is obviously resulted from our responsibility.
GURANTEE REGULATIONS
1. This instrument is warranted for the operation under normal use for 12 months from the date of
purchase.
2. This warranty does not cover the following defects:
a. Defect caused from the improper use and operation.
b. Defect caused from the use, operation and storage beyond the original specifications, designs and
conditions.
c. Defect caused from the renovations or repairs done by someone else than us or our
representatives.
d. Defect not caused from our responsibilities.
Battery Cover Screw
The correct size screw
must be used and fitted
to ensure battery cover
security, and safe
operation.