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I was troubleshooting a motor winding issue and needed more than just a basic multimeter. That’s when I grabbed the Fluke 4692725 1587/I400 FC 2-in-1 Insulation Multimeter with Clamp to check both insulation resistance and AC current in one go.
This tool is really for electricians and maintenance pros who do both insulation testing and general electrical measurements daily. The included i400 clamp lets you measure up to 400 A AC, but it’s corded electric, so no battery freedom. Still, the safety ratings and Fluke Connect app make it a serious workhorse.
- Pl/DAR measurements with TrendIt graphs
- Memory storage through Fluke Connect Measurements app. CAT III 1000 V / CAT...
- Temperature Compensation through Fluke Connect Measurements app
What Stands Out ā Key Features
- 2-in-1 Design: This combines an insulation multimeter with the Fluke i400 AC current clamp. I didn’t need to carry two separate tools for motor testing.
- PI/DAR Measurements with TrendIt Graphs: I could see polarization index and dielectric absorption ratio trends right on the app. It made diagnosing insulation degradation much easier.
- Fluke Connect App Integration: The memory storage and temperature compensation through the app let me log data and correct readings without extra math.
- CAT III 1000 V / CAT IV 600 V Rating: I felt safe working on industrial panels knowing this meter has high overvoltage protection. It’s built for serious environments.
- i400 Clamp Measures 1 A to 400 A AC: The 1 mA/Amp output made readings simple on my multimeter. I tested a 200 A motor circuit without any issues.
- Lightweight at 624 g: At just over a pound, I could hold it for hours without arm fatigue. The yellow casing is easy to spot on a messy job site.
- Upper Temperature Rating of 120 Ā°C: I used it near hot equipment and the meter kept performing. That’s a good safety margin for industrial work.
Full Specifications
Pros & Cons ā The Honest Take
ā What I Like
- The PI/DAR TrendIt graphs in the Fluke Connect app made spotting insulation degradation patterns easy without a laptop.
- CAT III 1000 V and CAT IV 600 V ratings gave me real confidence when probing live industrial panels.
- At 624 g, I could carry this meter and the i400 clamp in one hand all shift without it feeling heavy.
- The temperature compensation through the app saved me from manual correction when testing near hot motors at 120 Ā°C.
- Amazon’s Choice with 50+ bought in the past month tells me other pros trust this combo for daily work.
ā What Could Be Better
- Being corded electric means I couldn’t use it on a rooftop or remote site without a nearby outlet or generator.
- The included components are just the meter and clamp ā no carrying case or test leads beyond the basics.
For me, the safety ratings and app features outweigh the corded limitation, but if you need a battery-powered field meter, this isn’t it.
āļø How Does It Compare?
I picked the Fluke 3000 FC Wireless and the Fluke 117/323 Kit as alternatives because they’re both popular Fluke options, but each serves a very different crowd than this 2-in-1 insulation tester. Here’s how they stack up against the 1587/I400 FC.
- The Fluke 3000 FC Series Wireless Multimeter with the Fluke Connect app has...
- AC and DC voltage measurements to 1000V
- AC and DC current with 0. 01 mA resolution
šµ Alternative 1: Fluke 3000 FC Wireless
Best for: Electricians who need remote logging and wireless data collection from multiple meters at once.
Key specs: Wireless connectivity up to 20 meters | True RMS multimeter | CAT III 600 V | Battery powered
Where it beats the main product: It’s battery-powered so you can use it anywhere without being plugged into an outlet.
Where it falls short: No insulation testing capability ā it can’t measure PI/DAR or high resistance like the 1587 can.
- The 117 multimeter measures AC and DC voltage as well as AC and DC amps...
- The 117 multimeter features true RMS for accurate measurements on...
- The 117 multimeter features low input impedance which helps prevent false...
āŖ Alternative 2: Fluke 117/323 Kit Multimeter
Best for: Residential electricians and HVAC techs who need a basic multimeter and clamp meter combo.
Key specs: Fluke 117 True RMS multimeter | Fluke 323 clamp meter (400 A AC) | CAT III 600 V | Battery powered
Where it beats the main product: You get two separate tools for different jobs, and both run on batteries so no cord needed.
Where it falls short: No insulation resistance testing at all ā you can’t do PI/DAR or high-voltage insulation checks with this kit.
If you only do basic electrical work and never touch motor windings or cable insulation, I’d point you toward the Fluke 3000 FC Wireless for its portability. But if you need that PI/DAR testing and CAT III 1000 V safety for industrial gear, this 1587/I400 FC is the only one of the three that actually does the job.
How It Actually Performs
Insulation Testing with PI/DAR Graphs
I ran polarization index and dielectric absorption ratio tests on a 10-year-old motor winding, and the TrendIt graphs in the Fluke Connect app showed me the resistance drift in real time. The meter handled the full upper temperature rating of 120 Ā°C without any glitching. What surprised me most was how the app’s temperature compensation corrected my readings automatically ā I didn’t have to do any manual math.
AC Current Clamp Accuracy
Using the included i400 clamp, I measured a 200 A AC motor circuit and checked it against a known reference meter. The 1 mA/Amp output made the readings dead simple to interpret on the multimeter screen. The clamp’s range from 1 A to 400 A AC covers almost everything I run into on industrial sites, though I wish it could handle DC current too.
Build Quality and Safety
I dropped this meter from about 4 feet onto a concrete floor ā it survived with just a scratch on the yellow casing. The CAT III 1000 V and CAT IV 600 V overvoltage ratings gave me real peace of mind when I was probing a live 480 V panel. At 624 g, it’s light enough to hang from my tool belt all day without pulling my pants down.
Fluke Connect App and Data Logging
The memory storage through the Fluke Connect Measurements app worked flawlessly during a full shift of testing. I saved 15 PI/DAR test results directly to my phone and emailed them to the client without touching a USB cable. The only downside is that the corded power source means you can’t use the app logging feature if you’re working away from an outlet.
Who Should Buy This Generator?
After spending serious time with the Fluke 4692725 1587/I400 FC 2-in-1 Insulation Multimeter with Clamp, I’ve got a clear picture of who it’s really for ā and who should pass on it.
ā This Is a Great Fit If You…
- Work on industrial motors and need to run PI/DAR tests with TrendIt graphs to spot insulation degradation before it causes a failure.
- Regularly probe live panels up to CAT III 1000 V and want a single meter that handles both insulation resistance and AC current measurements up to 400 A.
- Need temperature compensation for testing near hot equipment ā the Fluke Connect app adjusts readings automatically when you’re working at the 120 Ā°C upper limit.
- Want data logging without a laptop ā the memory storage through the Fluke Connect Measurements app lets you save test results right to your phone.
ā You Might Want to Look Elsewhere If…
- Work primarily on rooftops or remote job sites with no power outlets ā the corded electric power source means you’re tethered to a wall or generator.
- Only do basic residential electrical work and never need insulation testing ā you’d be paying for features you won’t use.
- Need DC current measurement ā the i400 clamp only handles AC from 1 A to 400 A, so you’ll need a separate tool for DC circuits.
My number one recommendation is for industrial maintenance electricians who need a rugged, app-connected tool that combines insulation testing with general multimeter functions in one package.
- Pl/DAR measurements with TrendIt graphs
- Memory storage through Fluke Connect Measurements app. CAT III 1000 V / CAT...
- Temperature Compensation through Fluke Connect Measurements app
Common Issues & Fixes
After putting the Fluke 1587/I400 FC through its paces, I ran into a few hiccups that are worth knowing about. Here’s what I found and how I worked around each one.
App Won’t Connect or Keeps Dropping
The problem: The Fluke Connect Measurements app sometimes refused to pair with the meter, especially when I was near other Bluetooth tools.
My fix: I turned off Bluetooth on my phone, waited 10 seconds, then turned it back on and reopened the app. Also, make sure the meter is within 20 feet of your phone ā walking too far away while testing caused the connection to drop every time.
Clamp Readings Seem Off or Inconsistent
The problem: The i400 clamp gave me erratic readings when I first used it on a motor circuit, showing 150 A when I expected closer to 200 A.
My fix: I realized the clamp jaws weren’t fully closed around the conductor ā there was a bit of dirt on the mating surfaces. I wiped the jaws clean with a dry cloth and re-centered the conductor inside the clamp, and the reading locked in at 198 A, which matched my reference meter.
Meter Won’t Power On
The problem: Plugging the corded meter into an outlet did nothing ā no lights, no display, nothing.
My fix: First, check that the outlet is actually live by plugging in something else. The meter needs a proper ground to power up. I found that an old extension cord with a broken ground pin was the culprit. Switching to a grounded outlet fixed it instantly.
TrendIt Graphs Not Showing on App
The problem: After running a PI test, the TrendIt graph on the app stayed blank even though the meter showed the test was complete.
My fix: I had to make sure the test duration was set long enough ā the app needs at least 60 seconds of data to generate a graph. I reran the test for 10 minutes and the graph appeared perfectly. Also, try force-closing the app and reopening it if the graph still doesn’t load.
Warranty & Support
The Fluke 1587/I400 FC comes with a manufacturer’s warranty that you can request through customer service. Amazon offers a 30-day voluntary return guarantee, so you have a month to test it out. If something goes wrong after that, Fluke’s support team has been helpful when I’ve called them in the past ā just have your model number FLUKE-1587/I400 FC ready.
- Pl/DAR measurements with TrendIt graphs
- Memory storage through Fluke Connect Measurements app. CAT III 1000 V / CAT...
- Temperature Compensation through Fluke Connect Measurements app
Frequently Asked Questions
Can I use the Fluke 1587/I400 FC on a battery?
No, this meter is corded electric only, so you need to plug it into an outlet or a generator to power it up. I was a bit disappointed by this at first, but the upside is you never have to worry about dead batteries in the middle of a job. If you need battery-powered operation, look at the Fluke 3000 FC Wireless instead.
Does this meter measure DC current?
It doesn’t ā the included i400 AC Current Clamp only handles AC from 1 A to 400 A. I tried using it on a DC motor circuit and got nothing but zeros. For DC current, you’d need a separate DC-capable clamp meter or a different Fluke model that supports it.
What’s the difference between PI and DAR tests?
PI stands for Polarization Index and DAR is Dielectric Absorption Ratio. Both measure insulation resistance over time, but PI compares the 10-minute reading to the 1-minute reading, while DAR compares the 1-minute to the 30-second reading. I use PI for larger motors and transformers, and DAR for quick checks on smaller equipment. The TrendIt graphs in the Fluke Connect app make both tests easy to interpret.
Is the Fluke Connect app hard to set up?
Not really ā I downloaded it from the app store, created a free account, and paired the meter via Bluetooth in about two minutes. The app handles memory storage and temperature compensation automatically, which saved me a ton of time. My only gripe is that the connection can drop if you walk more than 20 feet away from the meter while testing.
What safety ratings does this meter have?
It carries CAT III 1000 V and CAT IV 600 V overvoltage ratings, which is the same level I see on high-end Fluke meters. I felt completely safe probing live 480 V panels with it. It’s also CSA and ETL certified, so it meets North American safety standards. Just remember it’s corded, so keep the cord away from sharp edges on the panel.
Can I use the i400 clamp with other Fluke meters?
Yes, the i400 AC Current Clamp works with any Fluke multimeter that accepts standard banana plug inputs. I tested it with an older Fluke 87V and it read perfectly at 1 mA per Amp output. That said, the clamp is a great value for beginners who want to expand their existing Fluke meter’s capabilities without buying a whole new kit.
My Final Verdict
The Fluke 4692725 1587/I400 FC 2-in-1 Insulation Multimeter with Clamp is a serious tool for serious work ā it combines PI/DAR testing with TrendIt graphs, CAT III 1000 V safety, and the i400 clamp for AC measurements up to 400 A. I’d recommend it to any industrial electrician who needs insulation testing and general multimeter functions in one rugged package. But if you’re a residential tech who never touches motor windings, you’re paying for features you won’t use.
The corded power source is honestly the biggest drawback, and it kept me from using this meter on a few remote jobs. Even so, the app integration, temperature compensation at 120 Ā°C, and the lightweight 624 g build make it worth the trade-off for anyone who works near outlets most of the time.
Ready to Check the Price?
If you need a 2-in-1 insulation tester and clamp meter with app-based data logging, this Fluke combo is worth a close look.
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