The updated INNOVA 3320 is a low price, auto-ranging digital multimeter mainly aimed at DIY hobbyists and auto industry technicians. A good first multimeter, it can do most of the things big brand, expensive multimeters do (to a degree) and has a useful battery test feature.
Though it struggles on power circuits – with limitations when testing AC current – it is ideal for troubleshooting car wiring and general electrical issues around the home. In short, this is a good little meter for the money and a best seller.
- Large display
- Measures AC milliamps, voltage, resistance
- Continuity checker
- Loaded battery tester
- Auto shut-off
- Size: 5.5″ (140mm) x 3.5″ (90mm) x 1.25″ (32mm)
- Weight: 6.4oz (180g)
- Probe leads
- Holder case
- Two 1.5V AA batteries
- Manual (innova 3320 manual)
In-depth Review of the INNOVA 3320
The INNOVA 3320, also marketed as the Equus 3320, is useful for measuring most electrical ranges. These include: AC/DC volts to 600V, AC/DC millivolts and milliamps, DC amps, resistance, and continuity (with beeper), plus it also boasts diode check. The battery tester is a main selling point and features color coded LED’s for clarity.
Another selling point is the auto range, which automatically works out the correct range of a given test input and is good for all settings, aside from the battery check. Although you have to manually select DC, AC and milliamps ranges, the auto ranging on this tester is a good addition.
The main disadvantage is the low range of AC amperage. There is only a milliamp range available, so testing circuits with AC current is pretty limiting (to 200mA). You can, however, check DC circuits up to 10A, albeit at timed intervals of 15 minutes as this meter is not fused.
On resistance, it can measure up to 20MΩ, while overall meter input impedance itself is quite high at 10MΩ. This is a respectable value that shouldn’t have an undue affect when measuring resistance in a circuit. Unfortunately, there is no capacitance range.
|DC voltage||5 ranges (200mV / 600V)||±(0.8%+5)||100mV @ 200V|
|AC voltage||4 ranges (2V / 600V)||±(1.2%+5)||10mV @ 20V|
|DC current||4 ranges (20mA / 10A)||±(1-2%+5)||100µA @ 200mA|
|AC current||2 ranges (20mA / 200mA)||±(1.5%+5)||10µA @ 20mA|
|Resistance||6 ranges (200Ω / 20MΩ)||±(1.0%+5)||10Ω @ 20kΩ|
Instructions are in English, French and Spanish.
Battery Test Function
This is one of the most useful functions of the 3320. It has dedicated checks of 1.5V, 6V, 9V, and 12V. Corresponding LEDs let you know the current status of the battery.
The LEDS are appropriately color-coded:
GREEN = good
YELLOW = weak
RED = replace
If neither LED lights up, that indicates the battery is holding less than 10 percent of its full charge and is thus no good.
While the ability to test batteries is nothing new on any multimeter, the Equus puts the circuit under a 10mA load to more accurately decipher a battery’s real condition. While this small current is not a perfect indicator, putting batteries under load is necessary when checking their status as they may put out an unreliable reading otherwise.
Stated accuracy of the battery tester: ± 5.0%
CAR BATTERY TEST
Regards testing for (‘parasitic’) draw – or current drain – this battery tester gauges voltage as opposed to measuring amperage, which is the setting you’d need if testing for draw. While multimeters with a 10A rating can perform this diagnostic check, those with a continuous 20A rating are recommended.
Note: bear in mind that draw tests should only ever be done when the engine is not running as current consumption in a car battery under load is very high.
Design and Build Quality
The INNOVA 3320 multimeter is lightweight and naturally not as robust as higher end meters, although it doesn’t really have to be when working in the home or on the car. Attributes include side mounted lead holders, a fold-out stand, and an elastic cord hook. It also has a handy rear strap for easy holding. The battery compartment is easy to access via two screws, and the probes are long.
The input dial is centrally mounted and slightly proud, with 13 selector stations – four of which are dedicated to the battery tester. Immediately obvious is the lack of buttons on this test meter, specifically a lock function. This is the type of thing one would expect in order to keep the overall cost down, although it does not detract too much and does have most features.
Display and Labels
The most eye catching facet of the 3320 multimeter is its large, clear display and digits. Although it is not backlit, this is an impressive feature for the price of the unit nonetheless. Labels are clearly displayed, such as ‘mV’ and ‘AC’ and there is also a low-battery icon indicator. A nice touch is the color coding of the various ranges – the battery check is enclosed in a green module, contrasted with red for DCV and blue for milliamps, etc. Continuity and diode test positions and separate.
Function and Performance
This INNOVA multimeter comes with three jack sockets: the main terminal / common / DC 10A. Other functions include an auto power-off (after 15 minutes of idle time) and an automatic zero adjustment function. The circuit board is quite well put together, with good components that should last. Reaction times are respectable given the meter’s price point.
Mechanically, the INNOVA 3320 multimeter has a rubber holster with corner guards to protect it when dropped. Electrically, overload protection is for the lower ranges only, with a 315mA/250V GMA-type fuse. The higher amperage function is un-fused, and it is thus essential that when reading high amp circuits this be done in short intervals only.
The input resistance is 10MΩ and it is safe for automotive and domestic situations. It can operate at temperatures down to 32°F (0°C) and to 104°F (40°C). Industrial meters typically have a wider operational temperature range, but the above is fine for the typical car depot and at home.
Best Suited To…
This multimeter is best for DIY enthusiasts and for those in the automotive industry – working cars, motorcycles, boats, trailers. You can easily diagnose faults in home wiring and electrical appliances with this tester, as well as examine electronic circuitry. It is also okay for working on basic computer networks and is especially tailored to testing batteries.
INNOVA 3320 Pros and Cons
- Large, clear display
- Auto ranging – good feature for the cost
- Accurate enough for small jobs
- Handy battery test function
- Battery life indicator
- Fold-out kickstand
- Elastic cord wrist strap
- Long, sheathed probe leads
- Auto ranging quite sluggish
- Low AC amperage range
- No capacitance range
- No hold function
- Display not backlit
The INNOVA 3320 is a capable tester for the home and automotive industry. If you need to test high amperage AC circuits or three-phase systems, it is best to plumb for a more substantial multimeter. It has most other functions and boasts a large display, battery check, and auto-ranging. For the money it can’t really be beat, but, if you need more features and power, the 3340 is a better all-rounder.