
Thank you very much for selecting our digital AC current
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.
1. FEATURES
● 80mmφ big window CT.
● DC mV analog data output for recorder.
● Continuous long time measurement available
2. SPECIFICATION
Accuracy: 23℃±5℃, less than 80% RH (50/60Hz)
Blanking of all digits except MSD1
"D・H" mark on LCD readout
DC 100mV to each range full scale (DC90mV/1800A)
DIGITAL CLAMP-ON TESTER
MODEL M-1800

Limitation of circuit voltage
AC2000V/1 minute between CT core and outer case
0℃ to +40℃, <80%RH (non-condensing)
-10℃ to +60℃, <70% RH (non-condensing)
Approx. 350 hours (by alkaline batteries)
Batteries (UM-4)……….….2
Instruction manual……..…1
Carrying case………...…….1
Cable for recorder output (MR-002)
4. DIMENSIONS AND PANEL FUNCTION
①Current transducer (Jaw)
②Jaw opening lever
③Data hold switch
④LCD display
⑤Range selector switch
⑥Power switch
⑦Wrist strap
⑧Output terminal for recorder
⑨Battery cover
3. 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 25V AC
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.

5. METHOD OF MEASUREMENT
Measurement of Line Current
1) Set the power switch to “ON” position.
2) Set the range selector switch to arrange appropriate to the current
to be measured.
3) Clamp the conductor of the circuit under test.
* Note: Clamp around only one conductor in the circuit to be measured.
4) Read the displayed value.
5) In a dark place or where it is difficult to read the display, use data hold switch.
6) After measurement, set the power switch to “OFF”.
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.
● Never make measurement 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 replace the batteries, loosen the screw and
remove the battery cover located on the unit back.
Insert two batteries (UM-4 or type AAA) with
new ones, observing polarity.
Use high quality batteries which are
guaranteed against leakage.
If the instrument is to be left unused for
a long period, remove the batteries
to prevent damage from leakage.

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.
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.
MULTI MEASURING INSTRUMENTS CO.,LTD.
Akihabara Murai Bldg., 7F, 1-26 Kanda Sakuma-cho,
Chiyoda-ku, Tokyo,101-0025 Japan
TEL : 81-3-3251-7016 FAX : 81-3-3253-4278
Home Page : http://www.multimic.com/