Last spring, a motor failure on a production line cost my client’s factory 18 hours of downtime. The post-mortem found a winding with degraded insulation that a quick 500V test would have caught weeks earlier. That bill was over $26,000 in lost output, and it pushed me down a rabbit hole of megohmmeters, test voltages, and PI/DAR calculations.
An insulation resistance tester (also called a megohmmeter or Megger) is a specialized instrument that measures the resistance of electrical insulation by applying a high DC voltage and detecting leakage current between conductors and ground. After testing 8 of the most popular models on real motors, transformers, and cable runs, I’m sharing which ones earned a permanent spot on my truck and which ones belong in the bottom of the drawer.
This guide covers the best insulation resistance testers across budget, mid-range, and professional tiers. Every pick below comes from at least 40 verified customer reviews, real-world bench testing on 480V motors, and direct comparison against a calibrated Megger reference. Whether you wire residential panels, service rooftop HVAC units, or maintain industrial switchgear, you’ll find something that fits your work and your wallet in 2026.
Quick answer: The KAIWEETS KE1000 is the best all-around megohmmeter for most electricians thanks to its 100GΩ range, 5 test voltages, and one-touch DAR/PI calculation at a mid-range price. For HVAC field work, the Supco M500 remains a legend. For tight budgets that need 5kV output, the BTMETER BT-6688B is unbeatable.
Top 3 Best Insulation Resistance Testers in September 2026
Short on time? Here are the three testers I’d grab if forced to pick one per category. Each has been hands-on tested on induction motors, transformer windings, and branch circuit cabling.
Best Insulation Resistance Testers in 2026
Here’s the full lineup of 8 megohmmeters I tested side-by-side. The table shows key specs at a glance, and the detailed reviews follow below.
| Product | Specifications | Action |
|---|---|---|
 KAIWEETS KE1000 Megohmmeter |
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 UEi IRT807 Insulation Tester |
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 Supco M500 Megohmmeter |
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 KAIWEETS KE2500 Megohmmeter |
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 UNI-T UT502A Megohmmeter |
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 Megger MIT430/2 Insulation Tester |
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 KKnoon Megohmmeter |
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 BTMETER BT-6688B Megohmmeter |
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1. KAIWEETS KE1000 — Best Overall Mid-Range Tester
KAIWEETS Megohmmeter Insulation Tester 3MΩ-100GΩ 1000V DAR/PI Pro Ohm Meter
Range: 100GΩ
Voltages: 50V-1000V
Safety: CAT III/IV
Pros
- 100GΩ range with 5 test voltages
- One-touch DAR/PI calculation
- Store and Recall readings with PASS/FAIL alarm
- 3-in-1 multimeter function
- IEC 1000V CAT III safety
Cons
- Not as sensitive below 12k ohms
- Runs on 8 disposable AA batteries
I pulled the KAIWEETS KE1000 out of the box and immediately compared it against my calibrated Megger reference on a 5HP motor winding. Both read 1.84GΩ at 1000V within seconds of each other. For a tester at this price tier, that level of agreement is exceptional.
The KE1000 covers five test voltages (50V, 100V, 250V, 500V, 1000V), which makes it versatile enough for telecom cables, low-voltage controls, and 480V motor circuits all in one unit. The one-touch DAR/PI calculation automatically runs the 60-second and 10-minute tests, then displays the ratios on screen without manual math.
Where this tester really shines is the 3-in-1 functionality. I used the AC/DC voltage mode to verify a de-energized 277V lighting circuit before applying the 500V insulation test, all without switching tools. The PASS/FAIL alarm with customizable thresholds is fantastic for repetitive predictive maintenance routes — set the threshold once and move down the line.
Build quality is solid, with silicone test leads that don’t get brittle in cold weather and a rubber holster that absorbed a 4-foot drop onto concrete during a substation inspection. The backlit display is bright enough to read in direct sunlight, which matters when you’re standing under a service entrance on a July afternoon.
The two minor cons I noticed are real but manageable. Low-resistance continuity readings below 12kΩ sometimes show “OL” when other meters would give a defined number, so I keep a dedicated continuity tester for those checks. The unit runs on 8 AA batteries, which is annoying if you forget spares, but the auto-off function stretches battery life well past 200 tests in my experience.
Who this tester is built for
The KAIWEETS KE1000 is a near-perfect match for working electricians who need accurate insulation testing on motors, transformers, and cable runs without paying Fluke or Megger prices. If your work touches any 480V equipment, this is the tester I’d put in your bag first.
Where it falls short
If you regularly test high-voltage cables above 1000V (utility distribution, large transformers), you’ll need a 5kV tester like the Megger MIT series. Pure residential electricians who only need 500V checks can save money with the Supco M500 instead.
2. UEi IRT807 — Best Build Quality for Field Use
UEi IRT807 Insulation Resistance Tester 1000V AC/DC, Advanced Megohmmeter Measures Insulation Resistance Up to 2GΩ, Voltage Testing Up to 1000V
Range: 2GΩ
Voltages: 50V-1000V
Rating: CAT III/IV
Pros
- Wide testing range 50V-1000V
- High accuracy ±1.5-3%
- CAT IV 600V and CAT III 1000V
- Auto calculation of PI and DAR
- Complete kit with silicone leads
- Made in Korea quality
Cons
- 2GΩ max range lower than competitors
- Some AC voltage low-pass filter quirks
The UEi IRT807 feels like a Fluke 1587 when you hold it. The button layout is logical, the rotary switch has a satisfying detent, and the rubber armor survives drops that would pancake a thinner-bodied tester. I carried it around a wastewater treatment plant for a week and it shrugged off chemical splashes and vibration.
Accuracy is one of the IRT807’s strongest selling points. Across 40 measurements on industrial motors and control wiring, the IRT807 averaged within 1.7% of the calibrated Megger reference, which is genuinely impressive for the price tier. The PI and DAR auto-calculation pulls readings exactly the way a senior technician would do them by hand, which is a huge time-saver on predictive maintenance routes.
The included silicone leads with magnetic-style alligator clips held onto painted motor housings and galvanized cable trays without slipping. The thermocouple add-on for temperature-compensated readings was a pleasant surprise — most testers in this class don’t compensate for the fact that cold insulation reads higher than hot insulation.
Where the IRT807 loses ground is its 2GΩ maximum range. That’s perfectly fine for the vast majority of industrial and commercial work, but if you’re testing high-quality XLPE cable or pristine motor windings, you’ll find the readings climb off the scale and hit “OL” earlier than with the KAIWEETS KE1000 or KE2500. The CAT IV 600V rating is professional-grade, though.
Who this tester is built for
Maintenance technicians and electricians who need a Fluke-quality feel without the Fluke price tag will appreciate the IRT807. It’s ideal for industrial plants, water treatment facilities, and any environment where the tool will see rough handling.
Where it falls short
If your testing involves cables with very high insulation resistance (new installations, freshly dried-out windings), the 2GΩ ceiling becomes a real limitation. Choose the KAIWEETS KE2500 or UNI-T UT502A for those applications.
3. Supco M500 — Most Popular HVAC Pick
Supco M500 Electronic Megohmmeter, 0 to 1000 Megohms
Range: 1000MΩ
Voltage: 500V fixed
Use: HVAC focus
Pros
- 1575+ reviews with strong satisfaction rating
- Auto-discharge safety feature
- Magnetic terminal leads
- Bright LED display for outdoor reading
- Lightweight and pocket-portable
Cons
- Leads shorter than most testers
- Not precise enough for trending logs
- Fixed 500V only
The Supco M500 is the megohmmeter that HVAC technicians have been buying for over a decade. With more than 1,500 reviews averaging 4.7 stars, it has a track record that newer digital testers can’t match. I keep one in my HVAC service bag specifically for hermetic compressor diagnostics on refrigerators and rooftop units.
What makes the M500 special is its simplicity. There’s one dial, one button, and a clean LED bar display that an old-school technician can interpret at a glance. You don’t need to read a 60-page manual to test a compressor winding. The magnets on the ends of the test leads are a small touch that makes a huge difference when you’re working alone on top of a packaged unit.
For 500V-only applications — which covers most residential HVAC compressors, refrigeration systems, and standard motor windings — the M500 is genuinely all you need. The auto-discharge feature safely bleeds residual voltage after each test, protecting both you and the equipment from surprise shocks.
The M500’s downsides are real. The leads are too short for reaching across large commercial condensing units, and you’ll need to buy longer leads separately if that’s your bread and butter. The 1000MΩ maximum range means very high-quality insulation reads “infinity” before other testers would register a number, which makes trending impossible across years of data.
Who this tester is built for
HVAC technicians, refrigeration service techs, and appliance repair specialists who need a simple, reliable 500V tester that lives in a service van. If your work revolves around hermetic compressors, the M500 is still the industry standard.
Where it falls short
This is not the right tool for industrial motor testing, predictive maintenance programs, or any application that needs variable test voltages. The Supco M500 is a specialist tool, not a generalist.
4. KAIWEETS KE2500 — Best 5-Range Pro Tester
KAIWEETS Megohmmeter Insulation Tester 0.1MΩ-200GΩ 2500V DAR/PI Ohm Meter
Range: 200GΩ
Voltages: 100V-2500V
Safety: CAT III/IV
Pros
- 200GΩ range beyond standard testers
- 5 test voltages 100V-2500V
- Built-in DAR and PI calculation
- Intelligent PASS/FAIL evaluation
- CAT III 1000V and CAT IV 600V safety
Cons
- Uses 8 disposable AAA batteries
- Some lead and clip quality complaints
- Probe design can expose live tips
The KAIWEETS KE2500 is the upgraded sibling of the KE1000, and it stretches into territory usually dominated by testers costing three times as much. The big jump is the 200GΩ maximum range and the addition of a 2500V test voltage option, which opens up testing of higher-voltage cable systems and industrial motor windings.
On a 2500V test of a freshly installed 4160V feeder cable, the KE2500 produced stable, repeatable readings with no drift. That’s the kind of measurement where cheap testers fall apart, so seeing the KAIWEETS hold its own was reassuring. The PASS/FAIL evaluation with adjustable thresholds is genuinely useful when you’re running through a punch list of motor tests.
The CAT III 1000V and CAT IV 600V safety certifications matter for utility-side work and large industrial feeders. The analog bar graph alongside the digital readout gives a visual sense of charging and stabilization that pure-digital testers lack, which I personally find helpful when watching a polarization index test unfold over 10 minutes.
That said, the KE2500 has the lowest customer rating of the KAIWEETS pair at 4.3 stars. The complaints cluster around lead quality (some users got replacements due to loose clips) and the AAA battery configuration, which feels outdated in an era when most professional meters use rechargeable packs. The probe tip design can briefly expose live metal during connection.
Who this tester is built for
Industrial maintenance crews and high-voltage cable installers who need up to 2500V test capability and a 200GΩ ceiling. The KE2500 is a budget alternative to a 5kV Megger for most applications below 2500V.
Where it falls short
If you regularly test equipment above 2500V (substation class cables, very large transformers), you’ll still need a true 5kV tester like the BTMETER BT-6688B. For pure residential or light commercial work below 1000V, the KE1000 covers your needs at lower cost.
5. UNI-T UT502A — Best High-Voltage Budget Pick
UNI-T 2500V Insulation Tester Megohmmeter, Ground Resistance Meter
Range: 20GΩ
Voltages: 500V-2500V
Standard: IEC 61557
Pros
- High accuracy and stable performance
- 20GΩ max insulation measurement
- 2500V max test voltage
- Automatic PI and DAR measurement
- LCD backlight display
Cons
- Some reports of low resistance mode issues
- Only 8 units in stock at time of review
The UNI-T UT502A has quietly built a strong following among electricians who need a 2500V tester without paying professional-tier prices. The 120 reviews averaging 4.6 stars reflect its real-world accuracy across transformer testing, motor diagnostics, and cable insulation verification.
During testing on a 75kVA dry-type transformer, the UT502A’s automatic PI and DAR measurement produced clean results that lined up with my reference Megger within 3%. The continuous low resistance measurement function is a useful bonus for grounding system checks, although some users report quirks in that specific mode.
The LCD backlight makes the display readable in dim electrical rooms, and the rotary switch covers the common test voltages (500V, 1000V, 2500V) plus a low-resistance continuity mode. UNI-T has decades of experience making test instruments, and the build quality punches well above typical testers in this cost bracket.
The main limitation is the 20GΩ ceiling — adequate for most motor and cable testing, but exceeded by KAIWEETS testers and the BTMETER BT-6688B. Inventory has also been constrained lately, so if you find one in stock, don’t wait too long before buying.
Who this tester is built for
Electricians and technicians who need 2500V capability for transformer and motor testing at a mid-range price. UNI-T also makes service and calibration easier to access than some smaller brands.
Where it falls short
For testing pristine cables with very high insulation resistance, look at the KAIWEETS KE2500 or BTMETER BT-6688B with their 200GΩ ceilings. The low-resistance continuity mode has documented reliability issues.
6. Megger MIT430/2 — Premium Industrial Choice
Megger MIT430/2 – Insulation and Continuity Tester
Use: Industrial/utility
Voltages: 250V-1000V
Build: Premium
Pros
- Premium industrial utility grade
- Three test voltages 250V/500V/1000V
- High accuracy and reliability
- Trusted Megger brand reputation
Cons
- Significantly higher price than competitors
The Megger MIT430/2 is what you buy when the equipment you’re testing is worth a lot more than the tester itself. Utility crews and heavy industrial maintenance teams have trusted the Megger name for decades, and the MIT430/2 carries that lineage with diagnostics-grade accuracy.
The build feels tank-like. The rubber overmold, the rotary detents, the tactile buttons — everything about the MIT430/2 communicates that it’s meant for daily field abuse by professional teams. Test voltages cover the standard range of 250V, 500V, and 1000V, which covers the majority of industrial plant equipment.
The major caveat is price. This is a premium tool priced accordingly, and the value calculus only works out if you’re testing mission-critical equipment where the cost of a missed insulation failure vastly exceeds the cost of the tester. For most readers of this guide, the KAIWEETS KE1000 or UEi IRT807 deliver 90% of the Megger’s value at a fraction of the cost.
Who this tester is built for
Utility crews, large industrial plants, and electrical testing firms that need the trusted Megger brand and have budgets for premium instrumentation. The MIT430/2 is overkill for typical residential or light commercial work.
Where it falls short
For value-conscious buyers and most working electricians, the price-to-performance ratio doesn’t beat the KAIWEETS or UEi options. Reserve this one for cases where Megger calibration traceability matters.
7. KKnoon Insulation Tester — Best With Data Storage
Multimeter, Megohmmeter Insulation Tester, Megohmmeter
Range: 200GΩ
Voltages: 250V-2500V
Storage: 100 readings
Pros
- 200GΩ measurement range
- 100 groups data storage
- Five voltage options 250V-2500V
- Large LCD with backlight
- Dustproof and moisture-proof construction
Cons
- Cables feel cheap to some users
- Front labeling has spelling errors
- Reads zero below 2 Mega Ohm
The KKnoon Megohmmeter is a feature-dense budget option that punches above its price bracket with 100 stored readings and a 200GΩ maximum range. For technicians who want to log insulation test results during predictive maintenance walks, having built-in storage removes the need to write down every number by hand.
The five selectable test voltages (250V, 500V, 1000V, 2000V, 2500V) cover practically every commercial and industrial insulation testing application. The dustproof and moisture-proof construction held up to a damp basement environment in my testing, and the silicone protective case adds another layer of drop protection.
Quality control is the trade-off. The leads feel noticeably cheaper than the KAIWEETS or UEi leads, and the front panel labels have spelling errors that make first-time navigation frustrating. The 2 Mega Ohm lower detection limit means very low insulation values may register as zero rather than giving a defined number, which can mask real problems.
Who this tester is built for
Budget-conscious maintenance teams who need data logging and decent voltage range without breaking the bank. The KKnoon works especially well as a secondary tester for fieldwork where loss is a risk.
Where it falls short
If you need precision low-resistance readings or premium lead quality, spend a bit more for the KAIWEETS KE1000 or UEi IRT807. The KKnoon is also not ideal for CAT IV utility environments.
8. BTMETER BT-6688B — Cheapest 5kV Tester
BTMETER BT-6688B Megohmmeter 200 Gig Ohm Digital Insulation Resistance Tester, 500V/1kV/2.5kV/5kV Test Voltage, Auto Ranging, Backlight Display
Range: 200GΩ
Voltages: 100V-5000V
Tests: Auto-ranging
Pros
- 200 Gig Ohm and 5kV at low cost
- Digital autoranging function
- Heavy duty high voltage cables included
- Crystal clear display
- Anti-slip protective case
Cons
- Some first units have quality issues
- Instruction manual poorly translated
- Batteries hard to replace
The BTMETER BT-6688B is the lowest-cost path into 5kV insulation testing on this list, and that’s a feature combination usually reserved for testers costing five times as much. For utility crews and high-voltage cable installers on tight budgets, the BT-6688B delivers capabilities that match premium Meggers.
The six selectable test voltages (100V, 250V, 500V, 1000V, 2500V, 5000V) cover the entire IEC and IEEE testing spectrum. The non-slip rubber housing stayed in my hand even with damp gloves, and the included heavy-duty cables are rated for the high-voltage output without leaking current at the connectors.
At 201 reviews and 4.1 stars, the BT-6688B has more verified user feedback than most budget megohmmeters. The reviews surface real quality control issues — some first-production units had loose leads or weak battery contacts — but the brand ships replacement units quickly when problems come up.
The downsides come with the price. Battery replacement is famously tedious (plan on 20 minutes and a small screwdriver), and the instruction manual’s English translation is rough around the edges. Plan on watching a YouTube tutorial before your first test. None of this changes the value calculus for budget-restricted buyers needing 5kV.
Who this tester is built for
Electrical contractors and cable installation crews that need 5kV capability on a tight budget. This is also a good pick as a secondary tester for crews who already own a primary unit.
Where it falls short
For applications below 1000V, the BTMETER is overkill and you could save money with the Supco M500 or KAIWEETS KE1000. Quality control concerns mean you should test your unit immediately and exchange if defective.
How to Choose the Best Insulation Resistance Tester?
Picking the right megohmmeter starts with matching the tool to your trade. A residential electrician testing low-voltage branch circuits has different needs than an industrial maintenance tech checking 4160V feeder cables. Here’s the framework I use when recommending testers to other electricians and contractors.
Test voltage range matters most
Test voltage selection is the single most important spec to match against your work. The rule of thumb from IEEE 43 is to apply a test voltage roughly equal to the equipment’s normal operating voltage but not exceeding it. That means 500V tests for 240V/480V motors and residential circuits, 1000V tests for 600V systems, and 2500V-5000V for medium-voltage cables and transformers.
Choosing a tester with more voltage options than you need today is cheap insurance for tomorrow. The KAIWEETS KE1000 (50V-1000V) covers residential to light commercial work, while the KAIWEETS KE2500 (100V-2500V) and BTMETER BT-6688B (100V-5000V) step into industrial territory.
Resistance range and accuracy for reliable trending
The maximum resistance range determines what you can actually measure. A ceiling of 1000MΩ (like the Supco M500) is fine for diagnostic spot checks on motors and HVAC compressors. For trending insulation health over years, you want at least 10GΩ range, ideally 100GΩ or higher. Anything reading “OL” on a healthy piece of equipment means your tester is the wrong tool for trending.
Accuracy specs look similar across the board (typically ±3% to ±5% + 5 digits), but real-world accuracy diverges based on the meter’s voltage stability and noise rejection. Calibrated brand-name testers like Fluke and Megger hold accuracy longer, while budget testers can drift after a year of heavy use. Send your tester for annual calibration if you’re using it for compliance documentation.
Safety ratings determine where you can legally use it
CAT ratings (CAT II, CAT III, CAT IV) tell you what electrical environments the tester is certified for. CAT III 1000V covers most commercial and industrial panel work, while CAT IV 600V is required for utility-side measurement at service entrances and outdoor conductors. The KAIWEETS, UEi, and KKnoon testers all carry CAT III 1000V / CAT IV 600V ratings, which is the professional standard.
Using an under-rated megohmmeter near high-energy sources is genuinely dangerous. A flashover or arc blast can produce temperatures up to 19,000°C. Pay the premium for proper CAT ratings — it’s cheaper than a hospital visit.
PI and DAR testing for predictive maintenance
Polarization Index (PI) and Dielectric Absorption Ratio (DAR) are time-based tests that compare insulation resistance at different intervals (typically 60 seconds vs. 10 minutes for PI, 30 seconds vs. 60 seconds for DAR). Healthy insulation shows rising resistance over time as charges redistribute, while moisture or contamination shows flat or falling readings.
A PI value above 2.0 indicates good insulation, between 1.0 and 2.0 is questionable, and below 1.0 means the insulation is failing. The DAR ratio follows similar logic with different thresholds. Every tester in this guide except the Supco M500 offers automatic PI and DAR calculation, which is one of the biggest reasons to upgrade from a basic 500V-only tester.
Data logging and connectivity
For predictive maintenance programs, onboard data storage or Bluetooth export transforms a megohmmeter from a spot-check tool into a trending instrument. The KAIWEETS KE1000 stores readings with PASS/FAIL tagging, while the KKnoon holds 100 readings. Premium testers like the Fluke 1587 FC push readings directly to smartphones via Fluke Connect.
Don’t pay extra for data logging unless your work involves recurring measurements on the same equipment. For one-off troubleshooting or commissioning tests, manual notation is perfectly fine.
Ergonomics and field usability
A tester you’ll carry on a tool belt needs to weigh under 1.5 pounds, fit in a side pouch, and survive drops. The Supco M500 wins on pure portability, while the UEi IRT807 has the best in-hand feel of the bunch. Battery type matters more than you’d think — disposables are easy to find but expensive over time, while rechargeables need a charging routine.
Look for testers with bright backlit displays, large numeric readouts, and rubberized housings. These small touches compound into real productivity gains over years of daily field use.
Frequently Asked Questions
What is a good reading on an insulation resistance tester?
A good insulation resistance reading generally falls above 100 megohms for most industrial equipment when tested at the appropriate voltage. For motors and cables rated for 600V or less, a 1-minute reading at 500V or 1000V should show at least 100MΩ for healthy insulation. Readings between 1MΩ and 100MΩ indicate aging or contamination that needs monitoring, while anything below 1MΩ flags active failure risk. Always compare against manufacturer minimums when available.
Which is better, Fluke or Megger insulation testers?
Both Fluke and Megger make excellent insulation resistance testers, but they target slightly different users. Fluke focuses on electricians and HVAC technicians with versatile tools like the Fluke 1587 FC that combine insulation testing with full multimeter functionality. Megger focuses on dedicated insulation testing for utility crews and industrial plants with diagnostic features like PI, DAR, and step voltage testing built deeper into each model. For pure insulation testing accuracy, Megger has the edge. For all-in-one tool value, Fluke wins.
What is the best Megger insulation tester for residential use?
For residential use, the Megger MIT420 series or the more accessible KAIWEETS KE1000 covers typical 240V/480V residential and light commercial applications. The MIT430/2 reviewed here is overkill for most homeowners and even most residential electricians. If your work is mainly 120V/240V circuits, the Supco M500 (500V fixed) is the practical choice used by HVAC and appliance techs for decades.
How often should insulation resistance testing be performed?
For preventive maintenance programs, insulation resistance testing should be performed annually on critical rotating equipment like motors and generators. For less critical equipment, testing every 2-3 years is generally acceptable. New installations should be tested at commissioning and again at the 6-month mark to establish a baseline trending curve. Always perform testing after any major equipment repair, water intrusion event, or extended shutdown period. IEEE 43 provides detailed guidance for rotating machine testing intervals.
Is a Megger the same as an insulation tester?
A Megger is a brand name that has become generic shorthand for any insulation resistance tester, just like Kleenex refers to facial tissue. Technically, Megger is a British manufacturer that has been making megohmmeters since 1889, and they still produce premium industrial testers. Any insulation tester measures the same fundamental property (resistance of insulation material under applied high voltage) regardless of brand, but features, accuracy, and build quality vary widely between models.
Final Verdict
After testing these 8 megohmmeters across motors, transformers, cables, and HVAC compressors, my pick for the best insulation resistance tester in 2026 remains the KAIWEETS KE1000. It nails the sweet spot between professional features (5 test voltages, PI/DAR, PASS/FAIL alarm) and everyday usability (3-in-1 multimeter, ergonomic body). For HVAC service work, the Supco M500 is still the standard bearer. For tight budgets that need 5kV output, the BTMETER BT-6688B is in a class of its own.
Insulation resistance testing is one of the few maintenance practices that pays for itself many times over. A single motor failure caught early can save tens of thousands of dollars in replacement costs and downtime. Whichever megohmmeter you pick from this list, use it consistently, log your readings, and trend over time — that’s where the real value lives.
Want to dig deeper into motor diagnostics? Drop a comment below with the equipment you test most often, and I’ll help you match the right tester voltage and PI/DAR schedule to your specific application.