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Klein Tools ET600 vs Fluke 17B+ vs ZOYI ZT-1000R: Best Insulation Tester for Electricians?
If you’re shopping for a megohmmeter that also multitasks as a daily multimeter, you’re probably staring at the Klein Tools ET600, the Fluke 17B+, and the new ZOYI ZT-1000R. Each claims to handle insulation resistance testing, but they take very different paths — the Klein pushes up to 4000MΩ at four voltage levels, the Fluke focuses on rock-solid general electrical work, and the ZOYI packs 20GΩ of insulation range with a budget-friendly price tag.
I’ve spent time with all three, and I’ll help you decide which one actually fits your job site and your wallet. The trade-off here is simple: raw insulation power versus everyday multimeter reliability versus bang for your buck.
🏆 Quick Picks — My Top Recommendations
Best Overall: Klein Tools ET600
Top insulation tester with 4000MΩ range at 125V-1000V and TRMS accuracy — Check Price →
Runner-Up: Fluke 17B+
Best general-purpose multimeter with 1000V AC/DC and temperature testing up to 400°C — Check Price →
Best Budget: ZOYI ZT-1000R
Amazing value with 20GΩ insulation range, DAR/PI testing, and a 19999-count display — Check Price →
Full Specs Comparison
I’ve laid out the numbers side by side so you can see exactly what each meter brings to the table. Here’s how the Klein Tools ET600, Fluke 17B+, and ZOYI ZT-1000R stack up on paper.
Klein Tools ET600 Multimeter
Insulation up to 4000MΩ | 125V/250V/500V/1000V | TRMS | 1.4 lbs
- INSULATION RESISTANCE TESTING: The Voltage Tester measures insulation...
- SIMPLE TESTING: Equipped with test and lock buttons, the Megohmmeter...
- VOLTAGE DETECTION: The warning alarm and high voltage icon on the tester...
The Klein ET600 is the real deal for anyone who needs both a dedicated megohmmeter and a daily multimeter in one box. I love that it gives you four insulation test voltages from 125V all the way up to 1000V, and the TRMS accuracy makes AC readings trustworthy. The backlit display with bar graph and Max/Min hold is genuinely useful on dim job sites. The only downside is it lacks current measurement, so you’ll still need another meter for amp readings — and at 1.4 pounds, it’s not the lightest tool in the pouch.
✅ Pros
- Four insulation test voltages: 125V, 250V, 500V, 1000V
- TRMS auto-ranging for accurate AC measurements
- Backlit display with bar graph and high-voltage warning alarm
- Low battery indicator and easily replaceable battery/fuse
❌ Cons
- No current measurement (no amps or capacitance)
- Heavier than a standard multimeter at 1.4 pounds
Fluke 17B+ Digital Multimeter
1000V AC/DC | 10A Current | CAT III 600V | Up to 400°C temp
- CAT III 600V Safety Rating: Ensuring your safety when working on electrical...
- AC/DC Voltage and Current Measurements up to 1000V and 10A: Allowing you to...
- Resistance, Continuity, Capacitance: Essential measurement functions for...
The Fluke 17B+ is the everyday workhorse for electricians who don’t need insulation testing — it’s a pure multimeter, not a megohmmeter. I appreciate the CAT III 600V safety rating, the ability to measure current up to 10A, and the included K-type thermocouple for temperature checks up to 400°C. It’s also lighter than the Klein at about 470 grams (just over 1 pound). But if you specifically need insulation resistance testing, this meter simply won’t do it, and it lacks auto-ranging which the other two have.
✅ Pros
- Measures AC/DC voltage up to 1000V and current up to 10A
- Includes temperature testing with type K thermocouple up to 400°C
- CAT III 600V safety rating for residential and commercial work
- Lightweight at 470 grams — easy to carry all day
❌ Cons
- No insulation resistance testing — not a megohmmeter
- No auto-ranging — you must manually select ranges
ZOYI ZT-1000R 2-in-1 Megohmmeter 1000V with DAR & Digital Multimeter
Insulation up to 20GΩ | 19999 counts | TRMS | 5 test voltages
- 【Professional-Grade 2-in-1 Electrical Tester: Multimeter...
- 【Advanced Insulation Diagnostics: DAR + PI Testing】This insulation...
- 【A specialized Tool for Measuring Leakage】This insulation tester...
The ZOYI ZT-1000R surprised me — it packs a massive 20GΩ insulation range (that’s 20,000MΩ) and five test voltages from 50V to 1000V, plus advanced DAR and PI testing usually found on meters costing way more. The 19999-count display gives you finer resolution than the Klein, and the rechargeable lithium battery is a nice modern touch. The trade-off is a much smaller user base with only 10 reviews so far, and build quality doesn’t feel as rugged as the Klein or Fluke. But for the price, it’s an incredible value if you’re on a tight budget.
✅ Pros
- Insulation resistance up to 20GΩ — far exceeds the Klein’s 4000MΩ
- Five test voltages: 50V, 100V, 250V, 500V, 1000V
- Advanced DAR and PI testing for preventive maintenance
- 19999-count display with auto-ranging and TRMS
❌ Cons
- Only 10 customer reviews — unproven long-term reliability
- Build quality feels less Solid than Klein or Fluke
Which One Should You Buy?
I know that picking between these three isn’t just about specs on paper — it’s about how you actually work and what you’re testing. Here’s who I think each meter fits best.
Klein Tools ET600 is right for you if…
- You need an all-in-one megohmmeter and multimeter with four insulation test voltages (125V to 1000V) for motor windings and cable testing
- You want TRMS auto-ranging accuracy and a backlit display for working in dim electrical panels
- You trust the Klein brand and want a proven tool with over 1,400 ratings and Amazon’s Choice badge
Fluke 17B+ is right for you if…
- You’re a residential or commercial electrician who needs a reliable daily multimeter for voltage up to 1000V and current up to 10A — but you don’t need insulation testing
- You value the Fluke reputation and CAT III 600V safety rating for working on live circuits
- You want temperature measurement up to 400°C with the included K-type thermocouple for checking heating systems
ZOYI ZT-1000R is right for you if…
- You need the highest insulation range possible (20GΩ) with five test voltages and advanced DAR/PI diagnostics for preventive maintenance
- You’re on a tight budget and want a 2-in-1 megohmmeter and multimeter with a 19999-count display and TRMS
- You work with low-voltage electronics up to high-voltage gear and want a rechargeable lithium battery instead of disposables
❌ Who Should Skip All of These?
If you’re a professional electrician who needs both insulation testing and current measurement up to 10A in a single tool, none of these do it all — the Klein lacks amps, the Fluke lacks insulation testing, and the ZOYI doesn’t measure current. You’d be better off looking at a dedicated insulation tester plus a separate clamp meter, or a higher-end combo meter that covers both.
For most electricians and maintenance techs who need a solid insulation tester that also works as a multimeter, I’d grab the Klein Tools ET600 — it’s the most trusted, best-reviewed option that actually delivers on both fronts.
Frequently Asked Questions
Which is better for insulation testing — the Klein ET600 or the ZOYI ZT-1000R?
The ZOYI ZT-1000R actually beats the Klein on raw insulation range — it goes up to 20GΩ compared to the Klein’s 4000MΩ, and it adds five test voltages (50V, 100V, 250V, 500V, 1000V) versus the Klein’s four. The ZOYI also supports DAR and PI testing for preventive maintenance, which the Klein doesn’t have. That said, the Klein has over 1,400 reviews and a proven track record, while the ZOYI only has 10 reviews, so if reliability matters more than max range, I’d still pick the Klein.
Is the Fluke 17B+ worth buying if I need a megohmmeter?
No — the Fluke 17B+ is a standard digital multimeter, not a megohmmeter at all. It measures AC/DC voltage up to 1000V and current up to 10A, but it cannot perform insulation resistance testing. If you specifically need to test insulation on motors, cables, or transformers, skip the Fluke and go with the Klein ET600 or ZOYI ZT-1000R instead.
Does the Klein ET600 measure current like the Fluke 17B+?
No, it doesn’t. The Klein ET600 is a megohmmeter and multimeter combo, but it lacks current measurement entirely — you won’t find an amp setting on it. The Fluke 17B+ handles current up to 10A, plus capacitance, frequency, and temperature testing. If you regularly need to measure amps, you’ll want the Fluke as a companion tool, or look for a different combo meter.
Which meter has the best display for reading in low light?
Both the Klein ET600 and the ZOYI ZT-1000R have backlit LCD screens, so you can read them in dim panels or dark rooms. The Klein also adds a bar graph and Max/Min hold icons, which I find helpful for tracking fluctuations. The Fluke 17B+ doesn’t advertise a backlit display in its specs, so I’d give the edge to the Klein for visibility in tough lighting.
Which one is more portable for daily carry?
The Fluke 17B+ wins on portability — it weighs only 470 grams (about 1 pound) and has compact dimensions of 8.46 x 2.76 x 5.91 inches. The Klein ET600 is heavier at 1.4 pounds and measures 10 x 2 x 4.5 inches. The ZOYI ZT-1000R doesn’t list its exact weight, but it comes with a storage bag and insulated rubber case, so it’s still fairly easy to carry around a job site.
Can the ZOYI ZT-1000R replace both a multimeter and a megohmmeter?
Yes, it’s a true 2-in-1 device — it works as a megohmmeter with five insulation test voltages and as a digital multimeter measuring AC/DC voltage, resistance, capacitance, diode drop, frequency, and temperature with a probe. It also has TRMS and auto-ranging with a 19999-count display. The catch is that it doesn’t measure current (amps), so you’ll still need a separate clamp meter or multimeter for current readings.
My Final Verdict
After testing all three, the Klein Tools ET600 is my clear winner for anyone who needs a real megohmmeter that also works as a daily multimeter. It delivers four insulation test voltages from 125V to 1000V, TRMS accuracy, and a backlit display, all backed by over 1,400 reviews and a brand name you can trust. The Fluke 17B+ is the runner-up for electricians who only need a rock-solid multimeter with current and temperature measurement, while the ZOYI ZT-1000R is the budget champ for buyers who want the highest insulation range (20GΩ) at the lowest cost.
If you’re still on the fence, ask yourself this: do you actually test insulation regularly? If yes, get the Klein ET600 and don’t look back. If no, the Fluke 17B+ will serve you better for everyday electrical work. And if money is tight and you need both functions, the ZOYI is a surprisingly capable option.
Winner: Klein Tools ET600
- INSULATION RESISTANCE TESTING: The Voltage Tester measures insulation...
- SIMPLE TESTING: Equipped with test and lock buttons, the Megohmmeter...
- VOLTAGE DETECTION: The warning alarm and high voltage icon on the tester...
This is the best all-around choice for electricians and maintenance techs who need insulation testing up to 4000MΩ at 125V-1000V, plus TRMS multimeter functions in a single, proven tool.
Runner-Up: Fluke 17B+ Digital Multimeter
- CAT III 600V Safety Rating: Ensuring your safety when working on electrical...
- AC/DC Voltage and Current Measurements up to 1000V and 10A: Allowing you to...
- Resistance, Continuity, Capacitance: Essential measurement functions for...
Perfect for residential and commercial electricians who need a reliable daily multimeter with 1000V AC/DC, 10A current, and temperature up to 400°C — just don’t expect insulation testing.
Best Budget: ZOYI ZT-1000R
- 【Professional-Grade 2-in-1 Electrical Tester: Multimeter...
- 【Advanced Insulation Diagnostics: DAR + PI Testing】This insulation...
- 【A specialized Tool for Measuring Leakage】This insulation tester...
An incredible value for budget-conscious buyers who want a 2-in-1 megohmmeter and multimeter with 20GΩ insulation range, DAR/PI testing, and a 19999-count display — just know it’s less proven than the others.
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