The Extech EX430 multimeter is one of this US brand’s larger, mid-range priced meters. This is a general tool for a slew of electrical tasks, including HVAC, though is aimed mainly at hobbyists and home repair. It is a True RMS meter that can auto range and is rated to CAT-III.
- Auto/manual-ranging capability
- AC accuracy with True RMS
- Measures temperature
- Big backlit display
- Can measure current to 20A
- Data hold and relative modes
- Auto power-down function
- Probe connection warning
- Weight: 12oz (342g)
- Size: 7.36″ (187mm) x 3.2″ (81mm) x 2.0″ (50mm)
- Test leads
- Type K thermocouple
- Battery (9V)
- Hanging strap
- EX430 user manual (online pdf)
Complete Review of the Extech EX430
You get generous voltage ranges with this meter, from 400mV in both AC and DC, up to 1000V DC and 750V AC. Amperage is touted from 400µA up to 20A in AC and DC. Bear in mind, however, that this is a category III-rated device and testing high energies is not advised.
Constant test amperage capability of the Extech EX430 is 10A, with 20A for bursts of 30 seconds only. It’ll then need to sit and cool down for at least 15 minutes. Maximum resolution of the micro-amps range is down to 0.1µA.
Resistance and frequency ranges are pretty good, yet capacitance only extends to 100µF, which won’t be man enough for testing capacitors in certain electronic circuitry. Other test criteria include diode and continuity tests and a temperature input (via a type-K thermocouple).
The True RMS designation allows users to more accurately measure the output signal of AC devices that have distorted waveforms. This would be useful in certain electronics applications and for motor drives with variable speed control.
Though fairly large, the Extech 430 is quite slim, having a ribbed holster for a comfy grip. Other attributes include a 4000-count backlit display with large digits, and hold and relative modes. There’s also an auto power-off function.
The accuracy is stated at a basic DC rate of ±0.3%, although this is for a best scenario situation at the 400mV range. In comparison, the heavy duty EX530 has a much higher accuracy, albeit at more than double the price. The EX430 is more comparable with the better rated EX360.
Negatives: Auto ranging speed is relatively fast but the EX430 is prone to overshooting before settling on the correct reading. Continuity checks could also be quicker and the buzzer is a bit scratchy.
|DC voltage||400mV / 1000V||±(0.5%+2) @ 4-400V||0.1mV-1V|
|AC voltage (50-400Hz)||400mV / 750V||±(1.5%+6) @ 4-400V||0.1mV-1V|
|DC current||400µA / 20A||±(1.5%+3) @ 400µA-400mA||0.1µA-0.01A|
|AC current (50-400Hz)||400µA / 20A||±(3.0%+8) @ 400µA-400mA||0.1µA-0.01A|
|Resistance||400Ω / 40MΩ||±(1.0%+2) @ 40kΩ-4MΩ||0.1Ω-0.01MΩ|
|Capacitance||40nF / 100µF||±(3.0%+5) @ 400nF||0.01nF-0.1µF|
|Frequency||5Hz / 10MHz||±(1.5%+5)||0.001Hz-0.01MHz|
|Duty cycle||0.1% to 99.9%||±(1.2 %+2)||0.1%|
|Temperature °F||-4 to 1382||±(3.0%+3)||1°F|
|Temperature °C||-20 to 750||±(3.0%+3)||1°C|
It comes with a rubber boot with integral lead storage clips, stand and ergonomic ribbing, and is quite easy to operate despite the size. An included Velcro strap lets you hang it up for hands-free testing. This particular unit is made in China and is noted as not having the build quality of some of the other EX series by Extech. There are reports of issues with the dial selector switch and jack input connectivity and an overall cheap feel.
Interface: The display on the Extech EX430 is quite nice. It’s a standard 4000-count screen with fairly large digits and sharp contrast. There’s a backlight, too, although it may wash out when read at an angle. The dial turns about halfway for all ranges, on account of being auto-ranging. Most positions have their own range, aside from voltage where usage of the ‘Select’ button switches between AC and DC.
Not all meters have an auto power-off mode. This function can really save battery power, and money, since it comes with a more expensive 9V battery. There is also a low battery indicator. Other functions include a hold, to freeze the display, and a separate relative mode button for comparing results of previously recorded ones.
Though rated to CAT-III at 600V, there is minimal input protection on the EX430. It has glass fuses as opposed to tougher ceramic ones and lacks the refinement of other Extech multimeters. Fuse ratings are 500mA for the 400mA input and 20A for the 20A input.
Connection warning: The beeper will sound and an on-screen alert will appear if anything but amperage is selected when the test probe is inserted into an amperage input.
Pros and Cons
- Large, backlit screen
- Auto/manual ranging
- True RMS
- Temperature input
- Lacking build quality of other Extechs
- Needs better fuses
- Slim capacitance range
In the review of the Extech EX430, it’s an okay meter for home and auto projects, though is perhaps not suited to professionals. If you need to measure temperature, capacitance, require True RMS responsiveness and prefer auto-ranging, then it’s not a bad deal. Reported issues include an unreliable dial switch and loose leads.
Alternatives: The EX363 is more refined and some of its ranges are wider, though it is without temperature. The compact EX330 has all this, plus voltage detection, and is cheaper but doesn’t have a backlit display. A more solid alternative to the EX430 from another reputable brand is the Klein Tools MM200.