The 27II is part of a series of tough digital multimeters by renowned test equipment manufacturer Fluke. Taking its cue from the hugely successful 87V DMM, although not quite as accurate, it was built to work in harsher conditions and comes with an IP67 rating. It has the measurement ranges to suit both those into electrics and electronics.
With the Fluke 27II, you also get a high category rating (CAT-IV working with 600V to ground), such that it has the input protection to handle 8kV spikes at those energies. It is as tough as the highly rated 28II, but does not include all the features of that model, such as True RMS accuracy, temperature range or the higher resolution display. See here for the review of the Fluke 28II.
- Full range multimeter with rugged exterior
- IP67 rating – against dust and water ingress
- Measures amps, milliamps, micro-amps
- CAT-IV 600V rated
- CAT-III 1000V rated
- Average responding RMS
- Measures capacitance to 9,999μF
- Measures frequency to 200kHz
- Resistance, continuity, diode tests
- Min/Max and average recording
- Auto hold feature
- Size: 7.8″ x 3.9″ x 2.5″
- Weight: 1.5lb
- Meter (with holster)
- Three AA batteries
- Test leads (with probe end caps)
- Alligator clips
- Protective input jack caps
- Instruction booklet
- CD manual
Complete Review of the Fluke 27II
This tough multimeter is a part of a small niche of rugged devices by Fluke that are able to withstand hardy environments and also provide reliable and accurate measurements. Along with being able to stand up to drops of 10ft, it can operate in temperatures of between 5°F and 131°F, humidity to 95 percent, and be dunked in water. It is MSHA-certified to be used in mines.
The 27II is the entry level in this 20 Series range, believe it or not, with the 28II and 28II Ex sporting more ranges and higher specs again. But, with the 27, you can perform most measurements and checks that the average electrician and technician would need. This includes AC and DC voltage checks up to 1000V in a CAT-III category, a millivolts range, amperage up to 10A (or 20A for 30 seconds) and resistance up to 50MΩ. There are also milliamps and micro-amps positions.
Most multimeters on the market today have auto ranging as standard, but often suffer lag due to inferior circuitry. The Fluke 27II is fast and its display has a quick refresh rate to better discern changing signals. Min/Max and peak hold modes are very useful in this regard too, plus it comes with their patented AutoHOLD feature.
The main negatives are that there is no temperature scale, it is a little less accurate than others in the 20 Series and is an average-only responding RMS device. This means you won’t get accurate readings if measuring AC variable speed outputs in comparison with a True RMS device.
|AC voltage||5 ranges: 600mV / 1000V||±(0.5%+3) @ 40Hz-2kHz||0.1mV-1V|
|DC voltage||4 ranges: 6V / 1000V||±(0.05%+1)||0.001-1V|
|AC current||6 ranges: 600μA / 10A||±(1.5%+2)||0.1μA-0.01A|
|DC current||6 ranges: 600μA / 10A||±(0.2%+4)||0.1μA-0.01A|
|Resistance||6 ranges: 600Ω / 50MΩ||±(0.2%+1) @ 6kΩ-6MΩ||0.1Ω-0.01MΩ|
|Frequency||5 ranges: 199.99Hz / >200kHz||±(0.005%+1) @ 199.99Hz-199.99kHz||0.01Hz-0.1kHz|
|Capacitance||6 ranges: 10nF / 9999μF||±(1.0%+2)||0.01nF-1μF|
Display and Function
The 27II has a 6,000-count display, able to show 59.99 on a given range. It comes with a dual brightness backlight display and updates at around four times a second, which is a decent speed for monitoring changing signals. Although not as high a resolution as the 28 version, you also get a speedy bar graph built into the bottom of the display. It updates 10 times faster again and is able to pick up fluctuating signals along the lines of an analog meter.
The battery life is very good on this multimeter, at around 800 hours (without use of the backlight). Few multimeters can boast this level of battery longevity, which is courtesy of three AA cells as opposed to a 9-volter. The glow on the buttons in dim lighting is passive.
Build Quality and Protection
This is one of the hardiest meters out there, with close to a military grade spec on the casing and electronic input protection. The case is thicker than normal, contributing to its hefty weight, and it also sports O ring seals. The IP67 rating for the Fluke 27II means it can withstand dust and water ingress. Drop-test height certification is to 10ft and it is MSHA mine-safety approved.
Regards the electrical safety rating, it has CAT-III and CAT-IV ratings (to 1000V and 600V respectively), with over-voltage surge protection to 8,000V (8kV). This value is typically a lot more than other meter brands can withstand and, together with reliability, accuracy and attention to detail, is one of the reasons why Fluke meters are pricey. Overload protection on the amperage circuits is provided by a 440mA fuse on the mA/µA input and an 11A fuse on the 10A input. They are high quality, high rupture capacity fuses.
Pros and Cons of the Fluke 27II
- Very strong and well protected
- Watertight – IP67
- Uses cheaper AA batteries
- Accessible battery/fuse compartments
- Micro-amps range
- Fast auto-ranging and continuity checks
- Quite bulky and heavy
- No temperature
- Not True RMS
This is a great multimeter for general purpose work, as well as for advanced electrics and electronics testing, in harsh environments. It boasts industry standard input protection, as well as their excellent levels of reliability and accuracy, but takes this one further with a very hardy build quality that includes an IP67 rating.
As the entry level of the 20 series, the Fluke 27II review has a couple of other options above it. If your job description includes the checking of variable speed drives, for instance, you will need a True RMS device. The 28II offers this functionality, together with extra AC voltage bandwidth, a temperature range and greater accuracy. It is more expensive, but not prohibitively so.
Up again is the even more sturdily built 28II Ex, which has all of the features of the 28II, to include a very high level of mechanical protection and electrical input protection.
Optional: there are all sorts of extras to be had with any Fluke multimeter, to include better performing leads and alligator clips. Unfortunately, the 27II doesn’t come with a magnetic hanging strap, but one of these is a must as the thing is so darn heavy!