Isotech IDM101 User manual

Instruction Manual
IDM101 Digital Multimeter

EN FR IT DE JP

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ISO - TECH IDM101
Digital Multimeter
INSTRUCTION MANUAL

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1. Safety notes
This meter has been produced to comply with category II requirements under IEC publication 1010-1 "Safety requirements
for electrical equipment for measuring, monitoring and laboratory use".
The present operating manual gives directions which must be followed and points out precautions which must be taken if the
meter is to be used safely and kept in a safe state.
Terms used in the operating manual.
"Important" identifies conditions or operations in which there is a possibility of the multimeter or other equipment being
damaged.
"Warning" identifies conditions or operations in which there is a possible risk of injury or death.
Markings on the unit.
Attention — Follow the operating instructions.
Danger — Dangerous voltages may occur at these connections.
Symbol for double insulation
Symbols in operating manual
This symbol indicates important information.
Fuse
Battery
WARNING : To avoid hazards or the risk of electric shock or of the multimeter being damaged, voltages which may
exceed which may exceed 600Vd.c. or 600Vrms should not be measured. Never apply voltages of more
than 600Vd.c. or 600Vrms to earth to the "COM" input terminal.

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Important : To avoid damage to the meter,
– remove the probes from the item being measured before you change the function settings,
– never try to measure voltages which may exceed 600V or 600Vrms,
– and never try to measure voltages when the meter is set to the resistance measuring function (Ω).
Always use the fuses specified.
To avoid the risk of fire, you should only use fuses of the correct types of the voltage and current ratings specified on the
bottom of the meter.
It is strictly forbidden for "repaired" fuses to be used or for the fuse holders to be shorted out.
WARNING: Read this operating manual thoroughly before you use the meter and follow the instructions given in it when
you are using the meter.
Misunderstandings of the warnings given or the operating instructions and errors in following them may cause hazards or
serious injury and/or may result in damage to the meter or other equipment.

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2. Introduction
This multimeter is a compact, battery-powered, handheld measuring and testing device for service engineers, industrial use
and amateur electronics engineers and for testing and repairing pieces of equipment. The functions it can perform are as
follows:
Measurement of a.c. and d.c. voltages
Measurement of a.c. and d.c. currents
Measurement of resistance and capacitance
Continuity testing
Diode testing
Frequency and ADP measurement.
Unpacking and checking
When you unpack your new multimeter, the items you should have are these:
1. Digital multimeter
2. Set of test leads (one black and one red)
3. Operating manual
4. Batteries (fitted)
5. Rubber holster.

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3. Technical specification
3.1 General specification
This meter has been produced to comply with category II requirements under IEC publication 1010-1 "Safety requirements for
electrical equipment for measuring, monitoring and laboratory use". This standard of safety can only be guaranteed if the
maximum and minimum figures specified in section 2.2 are observed.
Display : 33⁄4 digit 4000 count LCD display with a 42-segment analog bargraph display. Higher resolution of up to 9999 in
frequency range.
Polarity indication : Automatic, positive if nothing indicated, negative indicated
Low battery voltage indication: "" shown if the voltage from the batteries drops below the operating voltage.
Range overrun : Highest digit flashes.
Display update rate Two per second for digital display,
20 per second for bargraph display.
1 per second for frequency measurements.
Automatic power off : Approx. 30 minutes after the function switch was last turned.
3.2 Ambient conditions
Maximum altitude : 2000m
Installation category : IEC1010 1000V category II
600V category III
Pollution degree : 2
Operating temperature : 0 to +50°C, 0 to 80% RH.
Storage temperature : –20 to +60°C, 0 to 80% RH (batteries not fitted)
Temperature coefficient : 0.15 x specified accuracy/°C, <19°C or >28°C
Supply required : Two 1.5V batteries (IEC LR03, AM4 or AAA)
Battery life (alkaline) : Typically 1000 hours

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Dimensions (L x B x H(mm)) : 185 x 86 x 32,
with rubber holster: 200 x 98 x 52
Weight (inc. batteries) : 0.37kg
with rubber holster 0.6kg
Accessories : Rubber holster, test leads, batteries (fitted) and operating manual.
3.3 Electrical specification
Accuracy is given as ± (measurement error + display error) and applies at 23°C ± 5°C and less than 80% RH.
Measurement error (%) is given as a percentage of the current measurement.
Display error (D) is given in units equal to the smallest increment able to be shown on the display.
3.3.1 D.c. voltage (Vd.c.)
Range Resolution Accuracy Over Voltage
protection
400mV 0.1µV ±(0.7% + 2D)
600Vd.c. or
600V rms
4V 1mV
40V 10mV
400V 100mV
600V 1V
±(0.5% + 2D)
Input impedance: 10MΩ.

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3.3.2 A.c. voltage (Va.c.)
Range Resolution Accuracy Over Voltage
protection
600Vd.c. or
600V rms
4V 1µV ±(1% + 5D)
50 to 60Hz
±(1.5% + 5D)
50 to 60Hz
40V 10µV
400V 100mV
600V 1V
Input impedance: 10MΩin parallel with less than 100pF.
A.c. voltage conversion: Mean measured - r.m.s. value displayed.
3.3.3 D.c. current (Ad.c.)
Range Resolution Accuracy Voltage drop
4mA 1µA
±(0.8% + 2D)
40mA 10µA
400mA 0.1mA
10A 10mA ±(1.5% + 4D) 1V (max.)
800mV (max.)

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3.3.4 A.c. current (Aa.c.)
Range Resolution Accuracy Voltage drop
4mA 1µA
±(1.5% + 5D)
40Hz to 1KHz
40mA 10µA
400mA 0.1mA
10A 10mA ±(2.5% + 5D)
40Hz to 1KHz 1V (max.)
800mV (max.)
Overload protection : mA jack: 1A/415V, 32 x 6.35mm quick-acting fuse.
A input terminal : 10A/415V, 32 x 6.35mm quick-acting fuse.
A.c. current conversion : Mean measured - r.m.s. value displayed.
3.3.5 Resistance (Ω)
Range Resolution Accuracy Overload protection
400Ω0.1Ω±(0.7% + 3D)
600Vd.c. or
600V rms
4kΩ1Ω
40kΩ10Ω
400kΩ100Ω
4MΩ1kΩ±(1.0% + 3D)
40MΩ10kΩ±(2.0% + 5D)
±(0.7% + 2D)
Open circuit voltage : 0.4V

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3.3.6 Capacitance
Range Resolution Accuracy Overload protection
4nF 1pF ±(1% + 40D)
600Vd.c. or
600V rms
40nF
400nF
4µF ±(1% + 4D)
40µF 10nF ±(1% + 4D) < 20µF
±(5% + 8D) > 20µF
10pF
100pF
1nF
Continuity testing:
Indication threshold : Approx. 40 Ω
Continuity indication : 2kHz tone
Input protection : 600Vor 600Vrms
Diode testing:
Measuring current : 0.6mA
Open circuit voltage : Approx. 3V
Input protection : 600V or 600Vrms
Frequency measurement:
Ranges : 100Hz, 1kHz, 10kHz, 100kHz, 10MHz
Resolution : 0.01Hz on 100Hz range
Accuracy : ±(0.1% + 4D)
Sensitivity : 40mVrms from 1Hz to 20kHz 400mVrms from 20kHz to 1MHz
Input protection : 600Vd.c. or 600Vrms

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ADAPT range (ADP)
Indication : 10 units of the lowest digit per mV.
Accuracy : ±(0.3% + 2D)
Input protection : 600Vd.c. or 600Vrms
4. Display and connections
The display, controls and test jacks are shown in Fig.1.
1. Digital display — The 33⁄4 digit 3999 count digital LCD display includes a 42-element analog bargraph display and has
automatic annunciators for polarity, decimal point, range overrun, store data, AC/DC, Ω/ "<", " Auto",
">", , REL. MAX. MIN. and unit symbols.
2. Rotary function and range switch — This switch is used to select functions and measuring ranges.
3. COM input terminal — Input for the common potential.
4. V-Ωinput terminal — Input for voltage and resistance measurement, diode testing, and capacitance, frequency and
ADP measurement.
5. mA input terminal — Input for milliampere current measurement.
6. A input terminal — Input for current measurement. The meter can measure currents of up to 20A but the time is then limited
to a maximum of 30 seconds.
7. Function button (blue) — This button is used to switch between a.c. and d.c. voltage and a.c. and d.c. current, between
resistance measurement and continuity testing, between diode testing and capacitance
measurement, and between frequency and ADP measurement.
8. MIN.MAX button — Pressing the MIN/MAX button selects the MIN/MAX store mode. The minimum and maximum values are
then reset to the level currently measured. The display annunciators ">" and "MAX" or "MIN" are
activated. In the MIN.MAX mode the minimum or maximum values are stored. The internal sounder will
operate if a new minimum or maximum value overruns the display capacity of 4000 units.

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By pressing the "Hold" button in the MIN/MAX mode you can stop the measurements from being recorded and by pressing it
again you can allow their recording to continue. If you stop the recording, the current measurement shown is held and the
bargraph display frozen.
In the MIN.MAX mode, the minimum or maximum value is shown on the digital display while the bargraph display continues to
show the normal measurements.
9. Relative button (REL)— Pressing the "REL" button causes REL to appear on the display and activates the relative mode.
When you do this, the value shown on the display is stored as a reference value and the display is
reset to zero. To exit the relative mode, hold the "REL" button pressed for two seconds.
In the relative mode, the value displayed is the difference between the reference value held in store
and the value currently measured, e.g. if the reference value is 0.04 Ωand the value currently
measured is 15.05 Ω, what appears on the display is 15.01 Ω.
10. HOLD button — Except in the MIN/MAX mode, this button is used to switch the data hold mode on and off. When the hold
mode is on, ">" appears on the display and the measurement shown is held until the hold button is
pressed again. The internal sounder will operate when the hold mode is switched on.
If the MIN/MAX button is pressed while the hold mode is on, the meter exits the hold mode and goes over
to the MIN/MAX mode.
If the hold button is pressed while the MIN/MAX mode is on, storage of the minimum or maximum values is
stopped, and it resumes again if the hold button is pressed for a second time.
During the hold mode the automatic power off is disabled.
11. Power reset button (PWR RST) — If the meter has switched itself off automatically, it can be switched back on by pressing
this button.
12. Manual range button — This button is used to select manual range setting and to change ranges. If the button is pressed
once, the "" annunciator on the display disappears. By pressing the button repeatedly, the
meter can then be set to the desired range. To revert to autoranging, hold the button pressed for
two seconds.

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13. Store button — In the store mode, "MEM" appears on the display and the last measurement made is stored.
The value stored is not deleted when the meter switches itself off automatically, but it is when the
rotary switch is turned to "Off".
14. Recall button — This button can be used to recall a stored measurement to the display. This is indicated by "" appearing
on the display and "MEM" flashing. The automatic power off is disabled. To cancel the display of the
stored value and exit Recall, press the Hold button.

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Figure 1
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5. Using the meter
The meter was produced and tested to comply with IEC publication 1010 "Safety requirements for electrical equipment for
measuring, monitoring and laboratory applications" and was in a reliable state when supplied.
This operating manual gives directions and warnings which are essential for the user to follow, to work safely and to ensure
the integrity of the meter.
TEST EQUIPMENT RISK ASSESSMENT (UK RECOMMENDATION)
Users of this equipment and/or their employers are reminded that Health and Safety Legislation require them to carry
out valid risk assessments of all electrical work so as to identify potential sources of electrical danger and risk of
electrical injury such as from inadvertent short circuits. Where the assessments show that the risk is significant then
the use of fused test leads constructed in accordance with the HSE guidance note GS38 ‘Electrical Test Equipment
for use by Electricians’ should be used.
5.1 Preparatory steps and directions to be followed
1. After you switch the meter on, wait for 30 seconds before you make the first measurement.
2. You must set the desired function with the rotary switch before you bring the probes into contact with the item to be
measured. Remove the probes from the item before you change the setting of the rotary switch.
3. If the meter is used in the vicinity of equipment which generates electromagnetic interference, the display may become
unstable or incorrect measurements may be displayed.
4. Keep the meter dry.
5.2 Measuring voltages
1. Plug the black lead into the "COM" input terminal of the meter and the red lead into the "V-Ω" input terminal.
2. Turn the function switch to the "Va.c." or "Vd.c." position.
3. Apply the probes to the source or load whose voltage is to be measured. The polarity of the red probe will be shown along
with the measurement.
3. If the measurement is higher than the range of the meter or the range which has been set manually, the internal sounder
will operate and the highest digit of the digital display flashes, while the three lower digits will go 0.

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5.3 Measuring currents
1. Plug the black lead into the "COM" input terminal of the meter. To measure currents up to a maximum of 400 mA plug the
red lead into the "mA" input terminal and to measure currents up to a maximum of 10A plug it into the "A" input terminal.
(The meter can also measure and display currents of up to 20A but currents of this level must not be applied to it for more
than 30 seconds.)
2. Turn the function switch to the requisite current range from "4mA" to "A" and set the meter to d.c. or a.c. with the function
button.
Note: If you do not know which range you require, start with the highest range and if need be repeat the measurement
in whichever lower range you then find to be required.
3. Apply the probes to the circuit to the measured.
5.4 Measuring resistance
1. Plug the black lead into the "COM" input terminal and the red lead into the "V-Ω" input terminal. (Note: The polarity of the
red lead is positive.)
2. Turn the function switch to "Ω<" and use the function button to bring "Ω" up onto the display.
WARNING : To avoid the possibility of injury and to protect the meter from damage, make sure that the item from which
measurements are to be taken is not live.
3. Apply the probes to the item whose resistance is to be measured. To obtain the greatest possible accuracy with low
resistances, set the meter to the 400 Ωrange, and before making a measurement short the probes together and press
the "REL" button. This will automatically correct for the resistance of the leads when subsequent measurements are made.

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5.5 Continuity testing with the internal sounder
1. Plug the black lead into the "COM" input terminal and the red lead into the "V Ω<" input terminal.
2. Turn the function switch to "Ω” and use the function button to set to continuity testing ("" will appear on the display).
3. Apply the probes to the circuit to be tested. The internal sounder will operate if the resistance is less than about 40Ω.
5.6 Diode testing
1. Turn the function switch to "" and use the function button to select diode testing ("").
2. Plug the black lead into the "COM" input terminal and the red lead into the "V -Ω-" input terminal. (Note: The red lead is
positive.)
3. Apply the probes to the diode to be tested. With a non-faulty silicon diode, the voltage shown in the forward direction will
be between 0.500 and 0.900V. With a faulty diode, "000" (short-circuit) or a reading of approx. 3.2V (open circuit) will
be shown.
4. When tested in the opposite direction (blocking direction), a reading of approx. 3.2V will appear for a non-faulty diode and
"000" (short circuit) or a different reading of less than 3.2V for a faulty one.
5.7 Measuring capacitance
1. Plug the black lead into the "COM" input terminal and the red lead into the "V -Ω-" input terminal.
2. Turn the function switch to "" and use the function button to select capacitance measurement ().
3. When measuring the capacitance of polarised capacitors be sure to apply the probes with the correct polarity.
4. Apply the probes to the capacitor whose capacitance you wish to measure.
Important : 1. The capacitor must be fully discharged before any measurements are made.
2. To obtain a more accurate measurement you are advised to use the relative mode (press REL button) to
correct for any stray capacitances.

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5.8 Measuring frequencies
1. Plug the black lead into the "COM" input terminal and the red lead into the "V -Ω-" input terminal.
2. Turn the function switch to "Hz ADP" and use the function button to select frequency measurement (Hz).
3. Apply the probes to the signal source.
Note: The two lowest digits on the display may not be stable at frequencies of less than 1kHz or more than 20kHz.
5.9 ADAPT measurement
1. Plug the black lead into the "COM" input terminal and the red lead into the "V-Ω-" input terminal.
2. Turn the function switch to "Hz ADP" and use the function button to select ADP measurement (ADP).
3. Apply the probes to the signal source.
6. Changing batteries
This meter is powered by batteries. To change the batteries, see Fig.2 and follow the instructions given below.
1. Remove the probes from the item from which measurements are being taken and switch the meter off.
2. Unplug the leads from the jacks.
3. Lay the meter front-face-down on a work surface which will not damage its front face.
4. Unscrew the three screws in the bottom half of the case.
5. Carefully lever up the end of the bottom half of the case closest to the LCD display until it unclick from the bottom half.
6. Withdraw the battery holder from the top half of the case and carefully take the batteries out of it.
7. Fit new batteries into the battery holder and fit the battery holder back into the top half of the case.
8. Fit the bottom half of the case back onto the top half, making sure as you do so that you do not catch the lead from the
holder between the two halves of the case. See that all the seals are properly seated and that the two hooked lugs are
correctly engaged in the top half of the case.
9. Screw the three screws back in.

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Fig.2 Changing batteries
Bottom half of case
Top half of case
1.5V battery
Battery holder