Extech Instruments EX230 User manual

User's Guide
Multimeter with IR Thermometer
Extech EX230

EX230-EU-EN-V1.2-09/102
Introduction
Congratulations on your purchase of the Extech EX230 Autoranging Multimeter. This meter
measures AC/DC Voltage, AC/DC Current, Resistance, Capacitance, Frequency, Duty Cycle,
Diode Test, and Continuity plus non-contact InfraRed Temperature and contact thermocouple
Temperature. Proper use and care of this meter will provide many years of reliable service.
Safety
This symbol adjacent to another symbol, terminal or operating device
indicates that the operator must refer to an explanation in the Operating
Instructions to avoid personal injury or damage to the meter.
This WARNING symbol indicates a potentially hazardous situation, which
if not avoided, could result in death or serious injury.
This CAUTION symbol indicates a potentially hazardous situation, which
if not avoided, may result damage to the product.
This symbol advises the user that the terminal(s) so marked must not be
connected to a circuit point at which the voltage with respect to earth
ground exceeds (in this case) 600 VAC or VDC.
This symbol adjacent to one or more terminals identifies them as being
associated with ranges that may, in normal use, be subjected to
particularly hazardous voltages. For maximum safety, the meter and its
test leads should not be handled when these terminals are energized.
This symbol indicates that a device is protected throughout by double
insulation or reinforced insulation.
PER IEC1010 OVERVOLTAGE INSTALLATION CATEGORY
OVERVOLTAGE CATEGORY I
Equipment of OVERVOLTAGE CATEGORY I is equipment for connection to circuits in
which measures are taken to limit the transient overvoltages to an appropriate low level.
Note – Examples include protected electronic circuits.
OVERVOLTAGE CATEGORY II
Equipment of OVERVOLTAGE CATEGORY II is energy-consuming equipment to be
supplied from the fixed installation.
Note – Examples include household, office, and laboratory appliances.
OVERVOLTAGE CATEGORY III
Equipment of OVERVOLTAGE CATEGORY III is equipment in fixed installations.
Note – Examples include switches in the fixed installation and some equipment for
industrial use with permanent connection to the fixed installation.
OVERVOLTAGE CATEGORY IV
Equipment of OVERVOLTAGE CATEGORY IV is for use at the origin of the installation.
Note – Examples include electricity meters and primary over-current protection equipment
WARNING
CAUTION
MAX
600V

EX230-EU-EN-V1.2-09/103
CAUTIONS
•Improper use of this meter can cause damage, shock, injury or death. Read and
understand this user manual before operating the meter.
•Always remove the test leads before replacing the battery or fuses.
•Inspect the condition of the test leads and the meter itself for any damage before
operating the meter.
•Use great care when making measurements if the voltages are greater than 25 VAC
rms or 35 VDC. These voltages are considered a shock hazard.
•Warning! This is a Class A device. This device can cause interference in residential
areas.
•Always discharge capacitors and remove power from the device under test before
performing Diode, Resistance or Continuity tests.
•Voltage checks on electrical outlets can be difficult and misleading because of the
uncertainty of connection to the recessed electrical contacts. Other means should be
used to ensure that the terminals are not "live".
•If the equipment is used in a manner not specified by the manufacturer, the protection
provided by the equipment may be impaired.
•This device must not be used by children. It contains hazardous objects as well as
small parts that the children could swallow.
•Do not leave batteries and packing material lying around unattended; they can be
dangerous to children.
•In the event that this device will be stored for an extended period of time, remove the
batteries.
•Expired or damaged batteries can be hazardous to skin. Use suitable hand gloves in
such cases.
•Do not short-circuit the battery. Do not place the battery near a fire.

EX230-EU-EN-V1.2-09/104
SAFETY INSTRUCTIONS
This meter has been designed for safe use, but must be operated with caution. The rules
listed below must be carefully followed for safe operation.
1. NEVER apply voltage or current to the meter that exceeds the specified maximum:
Input Protection Limits
Function Maximum Input
V AC/DC, Resistance, Capacitance, Frequency,
Temperature, Duty Cycle, Diode Test, Continuity 600 VDC/AC rms
μA or mA AC/DC 500mA fused
A AC/DC 10A fused
2. USE EXTREME CAUTION when working with high voltages.
3. DO NOT measure voltage if the voltage on the "COM" input jack exceeds 600V above
earth ground.
4. NEVER connect the meter leads across a voltage source while the function switch is in
the current, resistance, or diode mode. Doing so can damage the meter.
5. ALWAYS discharge filter capacitors in power supplies and disconnect the power when
making resistance or diode tests.
6. ALWAYS turn off the power and disconnect the test leads before opening the covers to
replace the fuse or batteries.
7. NEVER operate the meter unless the back cover and the battery and fuse covers are in
place and fastened securely.
8. If the equipment is used in a manner not specified by the manufacturer, the protection
provided by the equipment may be impaired.

EX230-EU-EN-V1.2-09/105
Controls and Jacks
1. IR Thermometer
2. Laser Pointer
3. 4000 count LCD
4. MAX button
5. MODE button
6. FUNCTION switch
7. mA, µA and 10A input jacks
8. IR Thermometer button
9. HOLD button
10. RANGE button
11. Positive input jack
12. COM input jack
Note: Tilt stand, test lead holders, and battery compartment are on rear of unit.
Symbols and Enunciators
Continuity
Diode test
n nano (10-9) (amps, cap)
µ micro (10-6) (amps, cap)
m milli (10-3) (volts, amps, cap)
A Amps
k kilo (103) (ohms, Hz)
M mega (106) (ohms, Hz)
Ω Ohms
V Volts
AC Alternating current
DC Direct current
ºF Degrees Fahrenheit
ºC Degrees Centigrade
Hz Frequency
F Farad (Capacitance)
% Duty Cycle
AUTO Autoranging
HOLD Display hold
SCAN IR temperature and laser active
12
3
4
5
6
7
8
9
10
11
12

EX230-EU-EN-V1.2-09/106
Operating Instructions
WARNING: Risk of electrocution. High-voltage circuits, both AC and DC, are extremely
dangerous and should be measured with great care.
1. ALWAYS turn the function switch to the OFF position when the meter is not in use.
2. If “OL” appears in the display during a measurement, the value exceeds the range you
have selected. Change to a higher range.
AC/DC VOLTAGE MEASUREMENTS
CAUTION: Do not measure DC voltages if a motor on the circuit is being switched ON or
OFF. Large voltage surges may occur that can damage the meter.
1. Rotate the function switch to the Vposition.
2. Press the MODE button to indicate “DC” or “AC” on the display.
3. Insert the black test lead banana plug into the negative COM jack. Insert
the red test lead banana plug into the positive Vjack.
4. Touch the black test probe tip to the negative side of the circuit.
Touch the red test probe tip to the positive side of the circuit.
5. Read the voltage in the display.
AC/DC CURRENT MEASUREMENTS
1. Insert the black test lead banana plug into the negative COM jack.
2. Press the MODE button to indicate “DC” or “AC” on the display.
3. For current measurements up to 2000µA, set the function switch to the µA
position and insert the red test lead banana plug into the µA/mA jack.
4. For current measurements up to 200 mA DC, set the function switch to the
mA position and insert the red test lead banana plug into the µA/mA jack.
5. For current measurements up to 10A DC, set the function switch to the 10A
position and insert the red test lead banana plug into the 10A jack.
6. Connect the test leads in series with the circuit under test.
7. Apply power to the circuit.
8. Read the current in the display.

EX230-EU-EN-V1.2-09/107
RESISTANCE MEASUREMENTS
WARNING: To avoid electric shock, disconnect power to the unit under test and
discharge all capacitors before taking any resistance measurements. Remove the
batteries and unplug the line cords.
1. Rotate the function switch to the Ωposition.
2. Press the MODE button to indicate Ωon the display.
3. Insert the black test lead banana plug into the negative COM jack.
Insert the red test lead banana plug into the positive Ωjack.
4. Touch the test probe tips across the device under test.
5. Read the resistance in the display.
CAPACITANCE MEASUREMENTS
WARNING: To avoid electric shock, disconnect power to the unit under test and
discharge all capacitors before taking measurements. Remove the batteries and unplug
the line cords.
1. Rotate the function switch to the CAP position.
2. Press the MODE button to indicate F units the display.
3. Insert the black test lead banana plug into the negative COM jack.
Insert the red test lead banana plug into the positive CAP jack.
4. Touch the test probe tips across the device under test.
5. Read the capacitance in the display.
FREQUENCY AND DUTY CYCLE MEASUREMENTS
1. Rotate the function switch to the Hz% position.
2. Insert the black test lead banana plug into the negative COM jack.
3. Insert the red test lead banana plug into the positive Hz jack.
4. Use the MODE button to select Hz or % (Duty Cycle)
5. Touch the test probe tips across the device under test.
6. Read the frequency or duty cycle in the display.

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CONTACT TEMPERATURE MEASUREMENTS (THERMOCOUPLE PROBE)
1. Rotate the function switch to the °F or °C position.
2. Insert the temperature probe adaptor into the negative COM jack and the positive TEMP
jack (the adaptor is labeled plus +and minus -)
3. Touch the temperature probe tip to a surface or leave
suspended in air.
4. Read the temperature in the display.
CONTINUITY CHECK
WARNING: To avoid electric shock, never measure continuity on circuits or wires that
have a voltage potential.
1. Rotate the function switch to the position.
2. Press the MODE button to indicate on the display.
3. Insert the black lead banana plug into the negative COM jack.
Insert the red test lead banana plug into the positive jack.
4. Touch the test probe tips to the circuit or wire you wish to check.
5. If the resistance is less than the continuity threshold, the audible signal will
sound.
DIODE TEST
1. Rotate the function switch to the green position.
2. Press the MODE button to indicate “ “ and “V” on the display.
3. Insert the black test lead banana plug into the negative COM jack and the
red test lead banana plug into the positive jack.
4. Touch the test probes to the diode under test. Forward voltage will
typically indicate 0.400 to 0.700V. Reverse voltage will indicate “OL”.
Shorted devices will indicate near 0V and an open device will indicate
“OL” in both polarities.

EX230-EU-EN-V1.2-09/109
NON-CONTACT INFRARED TEMPERATURE MEASUREMENTS
1. Rotate the function switch to the IR position. The upper right four digit temperature
display will switch on.
2. Press the MODE button to select °F or °C.
3. Aim the infrared sensor (top of meter) at the surface to be measured.
4. Press and Hold the IRT button to turn on the IR thermometer and laser pointer.
The laser pointer identifies the surface spot to be measured and “SCAN” will flash in
the display.
5. Read the temperature in the display.
6. The area of the surface to be measured must be larger than the spot size as
determined by the distance to spot size values listed in the specification table.
7. Release the IRT button to turn the IR thermometer and laser pointer off. “HOLD”
and the final measured value will remain in the display.
WARNING: Do not directly view or direct the laser pointer at an eye. Low power
visible lasers do not normally present a hazard, but may present some potential for hazard
if viewed directly for extended periods of time.
IR Spot to Distance Diagram
The 4:1 spot to distance ratio determines the size of the measured surface area with
respect to the distance the meter is held away from the surface.
IR Measurement Notes
1. The object under test should be larger than the spot (target) size calculated by the
field of view diagram.
2. If the surface of the object under test is covered with frost, oil, grime, etc., clean
before taking measurements.
3. If an object's surface is highly reflective, apply masking tape or flat black paint to the
surface before measuring.
4. The meter will not make measurements through glass steam, dust, and smoke.
5. To find a hot spot, aim the meter outside the area of interest then scan across (in an
up and down motion) until the hot spot is located.
1”
@6”
2”
@12”
4”
@24”
20mm
@ 120mm 40mm
@ 240mm 80mm
@ 480mm
OFF

EX230-EU-EN-V1.2-09/1010
AUTORANGING/MANUAL RANGE SELECTION
When the meter is first switched on, it automatically enters the AutoRanging mode. This
automatically selects the best range for the measurements being made and is generally
the best mode for most measurements. For measurement situations requiring that a range
be manually selected, perform the following:
1. Press the RANGE button. The “AUTO” display indicator will turn off.
2. Press the RANGE key to step through the available ranges until the range desired is
selected.
3. Press and hold the RANGE button for 2 seconds to exit manual ranging.
Note: Manual ranging does not apply to the Temperature, Diode and Continuity functions.
DISPLAY BACKLIGHT
Press and hold the IRT HOLD button for 2 seconds to turn the backlight on. The
backlight will automatically turn off after approximately 10 seconds or press and hold the
button again for 2 seconds to manually turn it off.
HOLD
The HOLD function freezes the reading in the display. Press the HOLD button momentarily
to activate or to exit the HOLD function.
Note: The HOLD button does not function in the IR measurement mode.
AUTO SLEEP
If no button is pressed the auto sleep feature will place the meter in sleep mode after
approximately 30 minutes of operation. If this happens, press any button to wake the meter
or switch the meter to OFF if it no longer in use.