Placed in the middle of the brilliant 70 Series of Fluke multimeters is the Fluke 77 version 4. One of their better priced units, it is ideal for electricians and auto engineers, with solid functionality and a very rugged, easy on the eye design.
With its clean lines, user-friendly interface and assured accuracy, the 77IV works well for most general purpose tasks, though is a bit lacking for electronics. It can be comfortably held in one hand and comes with an ergonomic sunken dial and tapered body and fits snuggly into toolboxes and draws.
This Fluke 77IV review takes a look at its functions, including TouchHold®, and accuracy levels, as well as its build quality and input protection.
- Very clean interface
- Large backlit display with bar graph
- Average RMS responding
- Amps / milliamps ranges
- Capacitance / frequency ranges
- Millivolts range
- Auto/manual ranging
- Auto hold feature
- Min/Max mode
- CATIII and CATIV rated
- Size: 7.3″ (185mm) x 3.5″ (90mm) x 1.7″ (43mm)
- Weight: 14.8oz (420g)
- 77-IV Meter
- 9V battery
- Probe leads
- Instruction manual
In-depth Review of the Fluke 77IV
The 77IV is a significant improvement over previous series 77 meters, with more functions, speed and accuracy. Although it doesn’t have the accuracy and resolution of the 177 and is only an average responding RMS multimeter, it is still solid and performs very well.
All the voltages have their own ranges – AC, DC and DC millivolts, while amps and milliamps are separately fused. Resistance and continuity also have separate range positions, plus this meter comes with capacitance so is okay for electronics. It does not have a micro-amps range, however, so there is only so much electronics work you can do with it.
Voltage can be measured up to 1000V in both AC and DC ranges, and it is CAT rated to III at 1000V. You can also measure service runs with the 77IV on account of its CATIV rating and it works equally well on the bench or in the field. Despite being compact and easy to carry around, it is very rugged and has a nice, large display.
Current can be measured up to 10A continuously (20A temporarily), while the overall accuracy is high, with DC volts having a basic ±0.3%. Continuity checks and the auto raging feature are responsive and the 77IV also comes with Fluke’s patented AutoHOLD feature (to lock data automatically). In addition is the Min/Max/Average mode, for capturing values of a fluctuating signal.
MAX RANGE: BEST ACCURACY / BEST RESOLUTION
DC voltage – to 1000V: ±(0.3% +1) / 0.1mV
AC voltage – to 1000V: ±(2% +2) / 1mV
DC current – to 10A: ±(1.5% +2) / 0.01mA
AC current – to 10A: ±(2.5% +2) / 0.01mA
Resistance – to 50MΩ: ±(0.5% +1) / 0.1Ω
Capacitance – 1nF / 9,999µF: ±(1.2% +2) / 1nF
Frequency – to 99.99kHz: ±(0.1% +1) / 0.01Hz
Note: Stated accuracy/resolution is not across the entire range.
Counts: ±(0.3%+1): where ‘+1’ = +1 count / digit.
Design and Build Quality
As with its predecessors and this brand in general, the build is excellent both inside and out. The Fluke 77IV review details an ergonomic over-molded body, which improves protection, lends excellent grip and looks good. Most multimeters today have a removable boot, and while this can be advantageous, it is not as neat.
The housing also features integrated probe lead holders on the rear, together with a tilting bail for measurements on the bench. Along with a strong mechanical build are good electrical properties, with impressive safety ratings and input protection to guard against spikes.
Design wise, it looks good, probably more so than most multimeters out there (in my opinion), including other Flukes. Its sleek lines and uncluttered interface make for a good user experience.
Function and Performance
This is a fast performer with uncomplicated functions and no unneeded features. Some of the cheaper multimeters may look good and work well for a time, but they tend to fail under harsh working conditions. Flukes just work and typically maintain accuracy for many years. The 70 Series in particular has been around for donkey’s years, with units from the 1980s still going strong.
Battery life on the Fluke 77IV is around 400 hours of typical use. Overuse of the backlight will lower this. Sleep mode and auto power-off modes help preserve the battery.
HOLD: freezes the display / auto hold shows next stable input automatically
MIN/MAX: records high, low and average values of a changing signal
RANGE: changes to manual ranging and steps between ranges
Select: changes input ranges (marked yellow on dial selector)
Backlight: turns on and off display LED
V/Ω/Diode (main terminal)
10A (10 amps)
Display and Interface
For a capable, professional multimeter, this is about as simple as it gets. With just a few buttons and range positions, it is difficult to get things wrong here. The dial is very clearly labeled and has a maximum of two functions per selector position, while the input jacks are equally easy to decipher.
The display is a combination of large digits (to 6000 counts) and a bar graph. Digits update around four times a second, with the bar graph updating 32 times per second to give an accurate representation of a given value in analog form – ideal for fast changing signals. There is also a backlight.
The Fluke 77 is rated to category IV @600V and category III @1000V. The current ranges are protected by 1000V (to ground) HRC fuses. These well engineered fuses protect the meter and user in the unlikely event of a catastrophic failure. They are safer and more expensive than glass ones. The 10 amp circuit has an 11A fuse and the milliamp circuit a 440mA fuse. In addition is solid input protection, consisting of current shunt, power resistor, MOVs etc, culminating in overvoltage surge protection to 8kV.
Pros and Cons
Fluke 77IV PROS
- Reliable and accurate
- Great build quality
- Separate voltage ranges
- Fast auto ranging and continuity check
- Responsive display and bar graph
- Battery compartment
- Auto hold
- Nice size
- Looks good
- No micro-amps
- Average RMS response
- No separate fuse compartment
- Doesn’t include case or hanger
- Cheaper brands can do similar
In the review of the Fluke 77IV multimeter, we have a device that suits electricians; basic enough to handle household wiring faults, to advanced troubleshooting of low and high power HVAC systems, industrial plants and basic lab work. It’s also a popular meter for automotive repair, but is not so useful for electronics due to lack of micro-amps range.
The difference with the Fluke 177 is the 77 is average RMS responding only, is not quite as accurate, has less resolution and is more expensive. It is good for most jobs, however.
Popular optional extras for both meters include a case, a TPAK magnetic hanger and better test leads.
Bottom line: they aren’t cheap, but the 70 Series of Flukes will take abuse and last for years owing to a sturdy design and great input protection.