Are you looking for a new multimeter to replace an older one? Or are you getting one for the first time? Here are two popular models in the Extech lineup. Let’s compare them to see which one will help you the next time you want to test a circuit.
Extech EX330 Autoranging Mini Multimeter with Built-In Thermometer with Type K Remote Probe
The EX330 won the EEVblog Multimeter Shootout Award, and it’s a favorite tool at Adafruit, the online store for electronics enthusiasts and makers.It is not a high-end pro tool but it is good enough for professionals and hobbyists to recommend.
First off, it’s autoranging, which means it selects the appropriate setting without the user having to decide which range of value to test first. For example, if there’s a resistor and the user doesn’t remember what the colored markings mean, the EX330 will find the amount of its resistance without the user having to test various value ranges one by one. All the user has to choose is which category they want to measure: voltage, resistance, current, and so forth. The large dial on the front of the meter is clearly marked for each category.If the user doesn’t want autoranging, the EX330 can also operate in manual mode and relative mode. Relative mode lets the user measure against a previously stored value.
Second, the EX330 has a very handy function that the EX430 does not have. The EX330 can detect AC voltage without contact, meaning without using the test leads. The LED lights up and the multimeter beeps. This can save a lot of time and even protect the user from being hurt by a live wire where none was expected.
Third, this multimeter can test for a lot of things, some of which are less commonly needed, like duty cycle. It measures current, AC or DC voltage, resistance, capacitance, continuity, and diodes. Extech also includes a temperature probe that can measure the temperature of surfaces or air.
Finally, the EX330 has a data freeze hold to keep the reading on the screen. The screen does not have a backlight like the EX430, but its digits are 1-inch tall and easy to see.The LCD readout has a 4000 count display, which is 3-3/4 digits. The basic accuracy is 0.5%, typical for this kind of digital multimeter and plenty of precision unless you’re working in a laboratory!
More features of the Extech EX330 multimeter
- Comes with a rubber holster, test leads, tilt stand, Type K bead wire probe to measure temperature, a manual, and 2 AAA batteries
- Rated CAT III, 600V, and CAT II, 1000V
- Has replaceable fuses
- Recommended operating conditions are under 70% relative humidity, under 7000 feet, and between 32 and 122 degrees F
- Auto power-off after 15 minutes and low battery indicator
- Weighs 9 ounces
- 1-year limited warranty
Extech EX430 True RMS Autoranging Multimeter with K Type, Capacitance, Frequency, and Duty Cycle
The EX430 has several features in common with the EX330. For example, it is autoranging and can also operate in manual and relative modes. Relative mode is activated by the REL button. One push saves the measured value, then the user makes a new measurement and the difference appears on the screen.
Unlike the EX330, the EX430 has True RMS for more accurate measurements of AC voltage. This means it corrects for interference from things like fluorescent lights and computer power supplies. For handling AC current, the EX430 is rated up to 750V. For DC current it is CAT II, 1000 V, unlike the EX330 which is only CAT III. The EX430 also has a button to light up the display in case the user is working in dim light. Its display is 2000 count (3-1/2 digits) and its accuracy is +/-0.5%.
Another nice addition on the EX430 is that it gives audible and visible warnings when the leads are misconnected or there is a problem with the fuses.
More features of the Extech EX430 multimeter
- Comes with a multi-position tilt stand, Velcro strap for hanging, rubber holster with test lead holder, test leads, Type K bead wire probe, 9V battery, and manual
- Auto power off
- Data hold to keep measurements on the screen
- Weighs 12 ounces, a bit heavier than the EX330
- Recommended operating conditions are under 80% relative humidity, under 7000 feet, and between 41 and 104 degrees F
- Longer 3-year limited warranty
For what kinds of projects do you want a multimeter? If you’re working a lot with alternating current (AC) and need accurate measurements, the EX430 has True RMS. The EX430 is also rated up to 750V AC and CAT III, 1000 volts, for direct current (DC), but you may need to buy an additional pair of test leads. Extech only includes a pair of CAT III leads.
If you don’t need the EX430 features that are aimed more at professional users, but just want a solid multimeter for projects around the house, consider getting the EX330. It has lots of positive reviews from electronics enthusiasts that use it frequently. It also has better resolution for sensitive projects with its 4000-count display.