User's Guide Mini Multimeter with Non-Contact Voltage Detector (NCV) Model EX330
Introduction Congratulations on your purchase of the Extech EX330 Meter. The EX330 offers AC/DC Voltage, AC/DC Current, Resistance, Diode, Continuity, non-contact Voltage Detection, Capacitance, Frequency, Duty Cycle, and Temperature (Type K) functions. Proper use and care of this meter will provide many years of reliable service.
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 DC or V AC 600V AC and DC mA AC/DC 500mA DC/AC A AC/DC 10A DC/AC (for 30 seconds max.
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 25VAC rms or 35VDC. These voltages are considered a shock hazard. • Warning! This is a class A equipment.
Controls and Jacks 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
Operating Instructions WARNING: Risk of electrocution. High-voltage circuits, both AC and DC, are very 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. Press the HOLD button to freeze a displayed reading NOTE: On some low AC and DC voltage ranges, with the test leads not connected to a device, the display may show a random, changing reading. This is normal and is caused by the high-input sensitivity.
AC VOLTAGE MEASUREMENTS WARNING: Risk of Electrocution. The probe tips may not be long enough to contact the live parts inside some 240V outlets for appliances because the contacts are recessed deep in the outlets. As a result, the reading may show 0 volts when the outlet actually has voltage on it. Make sure the probe tips are touching the metal contacts inside the outlet before assuming that no voltage is present. CAUTION: Do not measure AC voltages if a motor on the circuit is being switched ON or OFF.
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. 2. 3. 4. Set the function switch to the VDC position. Insert the black test lead banana plug into the negative COM jack. Insert the red test lead banana plug into the positive V jack. 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.
AC / DC CURRENT MEASUREMENTS CAUTION: Do not make current measurements at 10 Amps for longer than 30 seconds. Exceeding 30 seconds may cause damage to the meter and/or the test leads. 1. 2. 3. 4. 5. 6. 7. 8. 9. Insert the black test lead banana plug into the negative COM jack.
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. 2. 3. 4. Set the function switch to the Ω position. Insert the black test lead banana plug into the negative COM jack. Insert the red test lead banana plug into the positive Ω jack. Touch the test probe tips across the circuit or component under test.
DIODE TEST 1. 2. 3. 4. Set the function switch to the position. Insert the black test lead banana plug into the negative COM jack and the red test lead banana plug into the positive jack. Use the MODE button to view the icon on the display. 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.
FREQUENCY MEASUREMENTS 1. 2. 3. 4. Use the MODE button to view the Hz unit of measure on the LCD display. Insert the black test lead banana plug into the negative COM jack and the red test lead banana plug into the positive Hz jack. Touch the test probe tips to the circuit under test. Read the frequency on the display. % DUTY CYCLE 1. 2. 3. 4. 5. Set the rotary function switch to the Hz/% position. Use the MODE button to view the % unit of measure on the LCD display.
AUTO-MANUAL RANGE SELECTION When the meter is first turned on, it automatically goes into the Auto Range 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. 2. Press the RANGE key. The AUTO display indicator will turn off. Press RANGE to step through the available ranges until the desired range is selected. 3.
Maintenance WARNING: To avoid electric shock, disconnect the test leads from any source of voltage before removing the back cover or the battery or fuse covers. WARNING: To avoid electric shock, do not operate your meter until the battery and fuse covers are in place and fastened securely. This MultiMeter is designed to provide years of dependable service, if the following care instructions are performed: 1. KEEP THE METER DRY. If it gets wet, dry it immediately. 2.
BATTERY INSTALLATION and LOW BATTERY INDICATION WARNING: To avoid electric shock, disconnect the test leads from any source of voltage before removing the battery cover. LOW BATTERY INDICATION The icon will appear in the lower left-hand corner of the display when the battery voltage becomes low. Replace the batteries when this appears. BATTERY REPLACEMENT 1. Disconnect the test leads from the meter. 2. Remove the protective rubber holster as shown in the diagram. 3.
1. Removable Rubber Holster 2. Meter 3. Battery 4. Fuses 5. Compartment Cover 6. Rubber Holster REPLACING THE FUSES WARNING: To avoid electric shock, disconnect the test leads from any source of voltage before removing the fuse cover. 1. Disconnect the test leads from the meter. 2. Remove the protective rubber holster as shown in the diagram. 3. Remove the Phillips head screw located on the lower back of the instrument. 4. Flip up the fuse/battery compartment cover to access the fuses.
Specifications Function Range Resolution Non-contact AC Voltage detector 100 to 600VAC Resolution & accuracy do not apply since the meter does not display the voltage in this mode. The lamp at the top of the meter’s display flashes when voltage is sensed. DC Voltage 400mV 0.1mV (V DC) 4V 0.001V 40V 0.01V 400V 0.1V Accuracy ±(0.5% reading + 2 digits) ±(1.0% reading + 2 digits) 600V 1V ±(1.5% reading + 2 digits) AC Voltage 400mV 0.1mV ±(1.0% reading + 30 digits) (V AC) 4V 0.
Resistance Capacitance Frequency ±(1.2% reading + 4 digits) 400Ω 0.1Ω 4kΩ 1Ω 40kΩ 0.01kΩ 400kΩ 0.1kΩ 4MΩ 0.001MΩ ±(1.2% reading + 2 digits) 40MΩ 0.01MΩ ±(2.0% reading + 3 digits) 4nF 0.001nF ±(3.5% reading + 40 digits) 40nF 0.01nF 400nF 0.1nF 4μF 0.001μF 40μF 0.01μF 200μF 0.1μF 5.000Hz 50.00Hz 500.0 Hz 5.000kHz 50.00kHz 500.0kHz 5.00MHz 10.00MHz 0.001Hz 0.01Hz 0.1Hz 0.001kHz 0.01kHz 0.001MHz 0.01MHz 0.01MHz ±(2.5% reading + 4 digits) ±(3.5% reading + 4 digits) ±(3.
General Specifications Diode Test Continuity Check Temperature Sensor Input Impedance AC Bandwidth Display Overrange indication Auto Power Off Polarity Measurement Rate Low Battery Indication Battery Fuses Operating Temperature Storage Temperature Operating Humidity Storage Humidity Operating Altitude Weight Size Approvals Safety UL LISTED Test current: 0.3mA max., Open circuit voltage: 1.5V DC typ.
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.
