The wago lever nuts are tested to European and German standards, and they are good standards for safety. While it may have slightly higher resistance due to the busbar arrangement, it is far less likely to experience user error and a poor connection in a DIY situation. The locations I use these most are for light fixtures, which have low draw. Good demonstration and good data. That was a well designed experiment. Thanks for putting it out there!

I'm a licensed electrician. I've been working for 25 years. I've used Wagos for most of that time. We've used them in residential, commercial and industrial conditions. Lighting retrofits, new home construction, remodels, and pretty much everything including high amp loads. I've been back to some of those jobs months or years later for various reasons and been back inside some of the boxes with the Wagos installed. None were melted. All were perfectly fine. I've never had to go back to a job because of a problem with the Wagos. They have been used in Europe for decades. They are tested to German standards. They are UL approved. And this test also shows that fears of Wagos being unsafe are unfounded. They are just fine. They are not a problem at all. I understand why some are skeptical but Wagos are perfectly safe. I have them in my home wiring. Wagos are also clear so you can see how the wires are seated inside the device. You can't do that with wire nuts. You can't see inside to verify the wires are correctly seated. Wagos are also easier for a DIY to get right.

I want to clarify something Scott keeps saying which is a little misleading (and that is Wago's fault): Wago 221 lever nuts are a FAMILY of products with different current ratings and gauges of wire. The ones Scott is using are the 221-41X side of the family which are rated at 20A/300V. The X represents the number of conductors, so 221-415 is a 5-wire Wago. Now the misleading part: there are different Wago 221s for higher current applications up to 30A/300V and supporting conductors from 20-10 AWG. If you need Wagos for higher current circuits then those are what you need, and they are available in 221-612, 613, and 615 sizes. Sadly, no inline splice connector in the higher range yet.

2:41 I have the same IR camera and something you should be aware of is the the surface material you’re measuring will definitely affect the temperature value shown. The factor is called emissivity and needs to be taken into account. Shiny or polished surfaces have very different values than dull or matte ones. You should be aware of this when comparing temperatures. Tables are available and a common trick is to use a piece of electrical tape where you want to measure to ensure each test point has the same emissivity.

I’ve seen some shotty work done on home electrical components. It’s not uncommon to see a wire nut hanging on by a thread. I’d say if you know what you’re doing as an electrician you will get similar results from using either option (some prefer the ease of the WAGOs sure, but I mean in terms of function). But a poorly installed wire nut could actually be a bigger threat posed compared to the higher resistance of the WAGO connections.

I can only say one thing: If it is UL CSA CCA EU.... approved, you can use it without any worries, as long as it is used as intended. I have been working with those standards on an industrial base for almost 50 years now and trust me, you can rely on them. Also, spring terminals have been approved for industrial use for many years now!

I have been replacing my ceiling lights with integrated LED fixtures and exclusively used Wagos since the current draw is so much lower and is so much easier for me to install. No more hoping the stranded and solid wires will twist together.

For the comparative testing, it's simpler to just measure the voltage drop rather than doing all the temperature measuring, because the heat generated is basically that voltage drop times the current. That calculation is the amount of power being dissipated in the box, and easily compared between each other as well as the baseline.

There is another KZfaq video that tests Wago. They slowly cranked the amps up until the wires were smoking, but the Wago was not smoking. I love Wago. Much easier to use than wire nuts. You also have visual confirmation of the wire contacts. Wago is made in Germany and they have been in use in Europe for 20 years with no problems. Back in 1968 when I was studying to be an electrician we learned how to make solder splices like they did in the 1940s. After applying solder then wrap with rubber tape and then friction tape. I have run across old solder splices but I have never had to make one.

My experience with wire nuts is that they can be a bit tricky to get right, especially if you mix wire types. The Wago do allow you to transit between just about any wire types without risk of an unreliable connection.

You read my mind. After seeing you recommend Wago numerous times in your videos, I still hesitated when it came to my projects. “But the resistance is higher with the Wago; it’s safer to stick to wire nuts,” I told my self. Well, not any more! Thanks to your well-planned and well-run demonstration, I no longer have any hesitation. This is what I love most about your channel: you don’t just reach conclusions about different methods or parts, you take the time and effort to break them down and test them. Excellent work, yet again.

I have an older model mobile home, and if you have ever seen the nightmare of those plug-in receptacles, where there maybe 3 Romex wires at 1 receptacle, it will get a little spooky as to solve the issue of a replacement. So I came to KZfaq to learn how to make my own repairs, and is where I learned about the WAGO Lever Nuts. So I went to Amazon, I ordered a small bag of them. The day they arrived I fixed my first receptacle, and before I went to sleep, went back to Amazon and ordered the BIG variety box of them. I did this 2 or 3 years back and have not had any issues so far, and will purchase them again if they are needed! I have rheumatoid arthritis, and these are so much easier to use than wire nuts! Peace and love and stay safe everyone, and remember to turn off your main breaker, before you begin your work!

Great move plotting the limit temp to scale the three connection options properly. I may be a mechanical engineer, not an EE, but a good experiment is a good experiment. I go Wago from here on out. I'll take a few degrees delta T at max load over an non-robust connection any day of the week.

I am glad that you put in the max temp on the graph. It really put into perspective.

I rewiring my basement with these (no choice, there was cloth wire and no grounds in original wiring). The first J-box on the largest circuit goes 5 ways with a Wago 221. That circuit hits 10-12A quite a bit (Yes, I'm going to split that up after I get the fuse panel replaced)(Yes,, Fuse.. Not breaker) I was feeling for heat when I put in the Wago, and it barely gets above room temperature when at full load for that circuit for several hours. Wago's are awesome.

Very informative! Maybe, do another video measuring voltage drop under load comparing 10 wire nuts in series to 10 Wagos in series. I suggest comparing using both a heat gun, then a typical load, like an HDTV, fridge, or fan.

I've seen other videos of testing the 221 lever nuts. They don't begin to melt until around the 80 Amp mark.

Well done, I suspected the WAGO would be slightly more resistive (heat) however, it still works quite well and makes the jobs much easier. Cheers

I'm neither a teacher nor an electrician, but I'd show this to middle school kids as a demonstration of the scientific method in a real world scenario. You get a solid A for experiment design. Scottish-Canadian electrician W. P Marr patented the wire nut we know today in the 1930s. I'll betcha a hot pastrami and swiss on rye, a big-ass kosher dill pickle, and a cold beer that, if KZfaq had been around then, the guys who were married to solder-&-tape connections were making these same arguments. I'll add that I find it 'way easier to get Wagu 211s to lay flat in a box that even the smallest wire nut.

I am a DIYer, not an electrician. I have used Wago connectors and will continue to do so. After seeing your test, I feel more confident using them. Great test! I have learned so much watching your videos. Keep up the GREAT work.

I am a remodeling contractor, formerly an electrician once. I use the Wagos all the time on 15 amp circuits but was always not sure how they would hold up on a 20 amp kitchen line. This was fantastic video. Great job! I am confident to use them on 20 now. Sweet! Thank you!

First, thank you for taking the time to run this test and create this content. Very original and to the point. I REALLY appreciate it. I'll add, no one on any electrical channel or reddit ever seems to have an appreciation for how over-designed everything actually is. That means, you should use the approved connector, per it's instructions, that personally gives you the highest confidence. I can sweat copper and connect PEX. Both have good applications. But on a daily basis, I'm using PEX. However, on a DYI electrical, I use wire nuts because I think they are cheap and fine. I'd have zero problem with a wago too, if it came with a device.

Don't forget to consider the insulation on the conductors. Table 310.16 shows that the temperature rating of TW conductors is 60 degrees Celcius (140 Fahrenheit). I'm sure that many DIY'ers in your audience will encounter Romex using conductors with this temperature rating that was in use before the 1984 NEC required upgrade to 90 degree C for this cable, without realizing its lower temperature rating. Your video title "Debunking the Pros", in my opinion, actually VALIDATES the pros, because you've demonstrated that the lever connectors that you tested are significantly hotter. The pros also know that having hot connections leads to problems. One example of this is that the insulation on the conductors becomes brittle. KZfaqr GreatScott! also tested, and found that the resistance of your Wago 221 connectors was 14 times higher than wire nuts (2.2mo vs 0.15mo). So, yeah, you validated the pros. They know that what meets minimum legal requirements and what is advisable can be different things. The number of comments speaks to the fact that we really appreciate actual performance tests - please keep up the great work!!

IMO the Wagos give me more confidence that my connections will stay together, especially when connecting 3+ wires, and in many cases make tidying boxes easier. I'll never go back to wirenuts where I can help it.

All of these devices are listed (usually by UL here in the USA). As such they go through LOTS of testing to make sure they aren't hazardous, or are prone to do nasty things (like start fires!). Also note that the NEC is a FIRE code (sponsored by the NFPA!), so their main concern is making sure things don't start fires. So, these items are all safe when used "properly" (follow the instructions!).

What is attractive about the Wago product is its' ability to handle stranded wires as well as solid in a very straightforward and fuss-free manner. My house is done in wire nuts for the most part but any time work on a lighting fixture everything gets changed to Wago...

I switched to Wagos a couple of years ago and haven't looked back. They're better than wire nuts for many applications. like connecting stranded and solid wires, or connecting more than three conductors. You can visually check that all wires are fully inserted and it is easier to get everything in the box. Five 12 AWG wires in a blue wire nut with two full twists outside the nut (per code) is very difficult to stuff in a double gang or 4 square box. Wagos just make life easier.

As someone that uses these in the HVAC trade for making connections to fans, compressors and solenoids, I have a high respect for them in their uses. I have found using wire nuts in high moisture environments like the cooled boxes of walk-in coolers/freezers and reach-in boxes they perform better. The wire nuts have rusted on me and I have to cut wire back and re-terminate with a new device VS the WAGO I can lift the lever pull the old device out and connect the new one without having a rust issue and loosing wire length. I still have my questions about them in high vibration environments and therefor will use either a wire nut or a termination block. Thank you for the insight into the temperature issues that people voice and prove they are still a better option for DIYers to use since strand to solid wire is not easy for the novice to do. I do use them at home in automotive too but in low current applications.

Hats off to Scott for a good test. However, my dad was an industrial electrician. He taught me to always scrap the wire ends, carefully twist the conductors, trim, then add the wire nut. I will continue to do so, but may use Wagos in really tight spots. Thanks again.

I'd love to see a test of connectors that reviews the error rate. So -maybe 20 people, from middling DIYers to experienced electricians -each making a bunch of connections -including easy (two 14g wires) to more difficult ones (two solid and a stranded, or 5 solid) -with some in typical non-ideal conditions (overhead, semi-dark, short wires) -including some previously twisted and disconnected wires -and without extra instructions for the DIYers. Let them make it up as they see fit, or reading as much instructions as they decide. -then stuff back into a box, where some say the Wagos may have problems. Then see how many of the connections are reliable (wiggle and pull tests, maybe).

Excellent demonstration! This was under extreme conditions (i.e. higher than rated for the circuit being protected by a breaker) which tells me that under normal household use, you likely would not see those temps even with that slightly higher resistance. I'm not an electrician, but I do understand wire gauge, resistance, loads, etc. Really, the only limiting factor for the WAGO's is the price compared to traditional wire nuts or your baseline installation.

Very interesting. Your graphs show me exactly what I would expect. No surprises, no concerns. Great video!

I am a fan of them over the last five years.. I like how I can disconnect the load without messing with the Hot conductor. They can be a bit pricey, but I use them in certain applications for convenience, such as light fixtures, certain motors pieces of equipment I may have to revisit. General pipe and wire I stick to wire nuts and yes, there should be a class on wire nuts because they’re quite often miss used.

Great job giving real world test results. I feel that the Wago is superior. Your channel is presenting info for DIY users. For those of us who have done a lot of wiring over the years, a common failure point is using a standard wire nut incorrectly. The Wago is so difficult to use improperly that it greatly lowers any issues with connecting wires inside of boxes. There is still a gigantic safety margin in using Wago connectors and they are faster to install. For being totally very old school, I would have liked to see the temp comparison for joining the wires by twisting, soldering, and taping. I think it would be an even better result. For those who say wire nuts are safer so I am using them, then why aren’t they soldering them. Yes, way too slow. I feel that after making 500 joints, the number of poor joints with wire nuts will be much higher than joints made with Wagos. Wagos cost more but I feel are worth it.

Hi Scott, I always appreciate seeing people testing devices to see how they perform in real life situations. It is not like every breaker always will trip at the rated capacity... there have certainly been some that have been tested that were considerably over their stated trip point, which lends to the credibility of your testing above the rated limits. Wouldn't it be a disappointment if these created a dangerous situation after being certified by multiple regulatory authorities? One of the benefits of the Wago is it will be much harder for a non-professional to install them incorrectly. When my sister asked me to help her with a few things at her relatively new house I opened a light up and a wire pulled right out of the wire nut with next to no force on it. Very shoddy workmanship on the part of the professionals who installed it. I doubt the inspectors would check every single connection in a new build but more likely rely on randomly inspecting a certain number of connections and believe they are representative of the remaining work. Lucky for her this was a light that saw short runs rather than constant use.

As a HVAC tech I've been using WAGO for years. Wire nuts work fine and yes, you have to install them correctly. But I will tell you contrary to what all the WAGO naysayer "ELECTRICIANS" are trying to claim, the touting the supposed superiority of wirenuts. I can say, over decades of years of service, many times I have come across weak connections by "ELECTRICIANS" losing connections, particularly in multiple neutrals bundled. Also many older wire nuts I've seen with a hole burnt right through the end by heat.Usually caused by "ELECTRICIANS" poor connection technique or wrong size wire nut selection. So they are not with out their faults. I find the WAGO are fantastic for control wiring work, because you can join hard copper and stranded wires without the worry of a weak joint. Plus up to 5 wires joined together without worry of poor twisting technique. And they are removable Both work great BUT BOTH need to be installed correctly, and like all tools, each have their strength in a particular installation. The Naysayers seem to be the closed minded types.

For my own projects, saving room in the right junction box I have used the Wago 221, I would agree to keep it for 15 amp circuits, so many lighting applications are led using much less current! German standards for electrical engineering appear to be very well tested!

Good video. I believe long term results will show the true durability of the Wago lever nuts on high amperage loads, especially those loads that cycle on and off frequently. I think long term testing of the effects of the heating and cooling cycles of the spring mechanism of the Wago lever nut will be the true test for it. For example, look at the results of the backstab connections "which is basically a spring loaded connection" that a lot of people thought 30 or 40 years ago "or longer" was such a good ideal. Then look at the failure rate of those. I think Wago lever nuts are great for low amperage loads such as lighting circuits where the heat swings are less drastic. in 50 plus years of electrical work I have never seen a properly installed wire nut failure, that was "pre-twisted" regardless of what the manufacture's directions say". So I am staying with old school tried and tested methods,. P.S. I have seen a lot of non pre-twisted wire nut failures also in those 50 plus years, but that is just my opinion and you know what they say about those.

Thank you for covering this subject. Very informative. I did not have that question in mind,since I have been amazed with these Wago lever nuts ever since I’ve been watching some of these electrical channels using them in some of the examples I needed at the time - including yours. Heat max performance never crossed my mind, but I’m glad you addressed it.

This is pretty interesting and thank you for going the extra mile and using a high amperage load and examining it with an IR camera. You make really good points with regards the heat capacity. I have seen plenty of failures from loose lugs, bug nuts, stab in outlets, improper use of outlets as splice points, and you make a good argument for a way to splice wires easily, consistently and reliably.

I’d like to see this done with the Wago “Wall Nuts” and Ideal “In-Sure” push-in style connectors. I’ve used the Ideal version for a few years now, and just discovered Wago has a similar product. Never had a problem with them. They’re also half the price of the lever nuts, so that’s a big plus. UL approved, by the looks of it too.

I am regularly using WAGO 221 and have not had any problems so far. Takes less space and makes me more confident about the connection.

Best most comprehensive test I've seen yet. And, yes.... I do agree with other commenters on the pitfalls of wire nuts. It really doesn't take much giggling around for them to come loose if not done properlty (continue the twist 3 or 4 turns on the wires coming out on the wire nuts). Great job. I too was skeptical but certainly that was conclusive enough for me.)

I have a house built in 1900. Most of the wiring has been replaced but there are still a couple of runs that haven't been done yet, I have to go with my budget so a little at a time. Now the 2 wires left were very busted up in the breaker panel so i ran new romex from the breaker out to a junction box where i spliced the old and new wires together. I used wago connectors since the old wires were paper coated, not pvc, i was able to keep them from fraying. Sorry for the long post. They really helped in my situation.

Excellent video! The results are what I would expect- Wagos have more resistance but not enough to be an issue. Not even close. My personal belief is the issues that people have had with Wagos comes from not having the wire inserted straight and flat. If re-stripped prior to inserting all should be fine.

I have used Wago for years and love them. They are especially useful when wiring a box with a lot of wires. The space savings, while not part of the max conduit calc, makes a huge difference. Those wire nuts take a lot more space and Wago just looks better. The one caveat though is to make sure you don't accidently push a lever up when pushing the wires into the box. I had this happen once and it was a huge pain tracking it down.

I started using Wago terminals in the early 90's. After thousands of terminations (if not over a million at this point) not a single failure attributed to design. A handful of failures due to damaged or improper use only. Wago is one of the brands I place full confidence in. When they went residential, i couldn't have been happier as now i use them in my home. If your scared to use them, stay home and lock your doors, you are too afraid of everything.

Great perspective against the design max temperature. That view puts the Wago in clear perspective. I’m staying with my Wagos. Thanks.

For solid core copper wires, the Wago 221 are not the best choice. Wago 2273 are the best to use. 221s if you need to add stranded wire to the connection.

Awesome experiment. I started using the WAGOs after watching Everyday Home Repairs. I'm 70 years old and cannot put as much strength into wire twisting as I used to. I'm a home DIYer and really appreciate you and your channel. You are my "go to" electrical KZfaq channel. Thanks for all you do. BTW, I know that wiring outlets in parallel has been done by many KZfaq electrical folks, but I'd love to see your teaching on how-to for those circuits. Have a happy Thanksgiving and God Bless You!

In all of the discussions that have been going on about electrical connections there is one extremely important factor that no one has addressed and that is a gas-tight joint. In order to prevent degradation of the connection over time the contacting surfaces must not admit 'air' or oxidation will occur and the resistance will increase. Yes, copper oxidizes! Less than aluminum or brass but it does. A gas tight joint means: clean surfaces, enough joint pressure to maintain the tight fit, and enough compliance in the joint to keep the pressure when temperatures change. On crimped terminals the terminal barrel and the conductor must be squeezed so tightly that they essentially become one piece and no gas can penetrate the contacting surfaces. This is easily done with screw terminals and crimping. But point contacts and pressures insufficient to cold form the contacts into gas tight joints cannot make gas tight joints. The components just can't deliver the needed pressure over the required area, over time, to make and maintain a gas tight joint. The connection will run hotter and oxidize faster than a large area gas tight joint. If conductors are twisted tightly at least two whole turns then 'clamped' with a proper wire nut, then the joint will have enough area and pressure to not present an increased joint resistance. Same with screw clamped terminals with lots of contact area and pressure to maintain a copper-crushing tight joint. All this applies whether large conductors are involved or small, solid or stranded. Industry has for decades worked to create the hardware and methods and tools to create gas tight joints that are reliable for high and low voltages and currents. Look at all the wiring in aircraft. It's gas tight. NASA certifies components, tools and operators to assure this reliability. Why would anyone use any device that can't make or maintain such a connection? Cheap and easy and good enough is why. But for reliability that's not good enough. Push-in connections have shown this problem and many devices have failed with some causing fires. Why the heck would one want to use a device that truly isn't fit for use!!! I want zero possibility of such a joint failing with the resulting damage. Pete

Thank you for doing this video! I, too, have seen numerous videos saying that the wago's are dangerous/unsafe and was curious because I started using them per your recommendation. I am a relatively new diy'er and as such revisited my electrical projects and was surprised to find that the wire nuts, although wrapped with electrical tape, were not secured very well. I'm thankful I found your video for more reasons than one!

Excellent test! Pretty much what I expected from the resistance tests I have seen other KZfaqrs do- Wago runs slightly hotter, but not much. I'd personally still use wire nuts with pre twisted connections for high amperage circuits such as part of a pigtail on a receptacle circuit, but I'd have no problem at all using Wago connectors for loads of a few amps or less like a ceiling fan or light fixture. That's just my preference though, obviously both are completely viable choices.

It would be interesting to try compare solid wire to same gauge stranded, which will flatten against the bus bar, increasing the contact area.

Great information. What was the best, is when you trued up your graph. Using statistics and graphs to mislead is almost the oldest profession. In your graph using 5 degree increments, you get a much different message, deceiving message. Then you added the approved upper limit and the data dictates 20 degree increments and the truth really comes into focus. As several have mentioned, getting wire nuts "right" is a learned skill. I have seen experienced electricians get it wrong sometimes. For ease of use and very high probability of making the best connection, I say the safest choice is the WAGO lever nut.

🇨🇦/🇺🇸... A couple things. 1/ I would automatically tend toward using mechanically simpler mechanisms. 2/ Traditional wire nuts have some size overlap and so you can often ADD a circuit without changing to... hunting through your parts drawer... a new size. (not an issue for the pro who keeps an inventory on hand but sometimes an issue for the homeowner/handyman) 3/ Are a package of WAGO more expensive. (some people won't care... some will)

Like others that have commented, I was skeptical about the wago lever nuts. The test you just performed eased all of my concerns. Thanks for all the useful content you create. As a DIYer, it great to have a video or two to fall back on when I have a question.

Great video. I have switch to wago, like stated from others I have seen twist type come off or loosen over time. Like you stated the breaker will trip well before wago tolerance is meet.

I’m in Australia and we don’t use wire nuts. It’s a screwed connector. Twist the wire first and put it in the connector and do up the screw. These work with all types of wires and I think they are safer than a wire nut. Since I found the Wago connectors I’ve been using them a lot of the time. Awesome for fault finding. It does have limitations if you want to put a few wires into one connector and have limited space. Most of my work is with fire alarm systems and the Wago are the best as the current and voltages are low and unless you do a really crap job of the install there wouldn’t be many connections along the circuit to cause an issue

What I think about Wago is that a 5 deg difference means nothing and that they are safe to use in any situation when installed per manufacture recommendations and within specs of the device and connector. I also think they are so much easier and faster to use AND a big selling point is that they make adding a new device or swapping out an existing device super-fast and easy. Also, I would say that for a homeowner with limited experience, you probably get a better connection. Wago are much easier to do right than wire nuts and they support a wider range of AWG. I have seen many professional electricians us the wrong wire nut because of not looking at the capacity chart on the wire nut package (if they even have the package to refer to.

Form most circuits, Wago is the best solution. For a really high amp circuit ( 30+ ) I prefer split bolt connectors. But they take up a lot of space and need insulation. LED lights have really helped to cut down circuit loads, so Wago is great.

The Wago are well within spec and the chance of a DYIer messing up the wire nut connecting is way greater. If the connection for the wire nuts is not secure then you will get way more heat.

Also, while the lever nut bus bars may not seem like a lot of surface area contact, one should keep in mind the cross-section of a wire, even 12 or 10 gauge, isn't that huge either. Yeah, the wire is solid (or stranded) copper, while the levernut is pressed physical contact, but if the bus bar is long enough, that shouldn't be a problem.

Since I used WAGO connectors on my daughter's old house (vintage 1930's with an updated 100Amp panel), I very much appreciate your demonstration. I'm not concerned about the outlet temp readings in her house as she would not put a circuit under the loads you used.

Awesome Test. WAGO will be my go to for now.

A very useful video. I would say balancing out the slightly higher temps encountered with the Wago, you have a greater assurance the connection was made in an approved manner with the Wago. I would suspect there are more wire nuts where the workmanship of the connection is sub-standard, resulting in a hotter connection when in use. I would suggest to the Wago people that they consider coming out with an "industrial" line where they make the part out of heavier materials and maybe they could match or even improve on the performance of the wire nut. Again, great job!

I salute you for actually doing the experiment. It would be interesting to see a fourth group, with the wire nut with a pre-twist.

The biggest concern using any kind of connector that relies on a spring mechanism is metal fatigue. Thy would be great for temporary builds but I'd never use them for long tern application. As the metal spring ages it looses its springiness and relaxes it's hold. A relaxed hold also has the potential for arching and is a fire hazard.

These are great. UL Listed safe and millions are in use right now.

Excellent test! I think more temperature testing videos would be great content. Maybe try different connectors like the Ideal push in or test the difference in temperature between things like pre twisting wire nut connections or screw terminals vs back stab terminals. Measuring the voltage drop across the connectors while loaded would give us another great data point too.

Where I am a bug fan of the Wago lever nuts is for the final connection from the solid house wiring to the multi stranded wiring of lights. The ease of connecting these two types sold me on them.

Hey Scott, great video and great test. I’ve been a bit concerned with the lower contact area in the Wagos and stopped using them after reading some reviews. Your test is a good way to debunk the myths. I’m going to start using the Wagos after seeing this test. Thanks.

An electric heater in the style you are using is a great device to use for creating heat in the wire run. I would like to see this test replicated on a 30 amp outlet with a wire welder or some higher amperage device. Just to see if the higher amperage changes the variance in this test and what percentage increase in temperature occurs in the wire nut vs WAGO. Keep up the good work!

The difference between 105 degrees and 115 degrees is not enough to worry about. More importantly, that 10 degree difference was in a circuit that was overloaded with unrealistic current flows. It would be interesting to see how the Wago connector performs in a 15-amp circuit.

Great video with good info! Have heard people talking about higher resistance of WAGO.

Good morning Scott, That was an EXCELLENT test you did. That just really proves just how good these 221 Wago`s are. I just love these little things. You have wonderful and helpful videos. Keep up the great work.

This like when plumbers were confronted with PEX and shark bites. “The world is going to come to an end”. I have used the stab ins for years and now the lever types and they work great.

I saw a test where someone ran so much current the insulation on the wire melted off, and the Wago nuts were still okay. In fact, the wire nuts melted, leaving just the steel helix around the wires. But the Wago plastic was still intact (although I'm sure it was hot).

Good info, thanks. I was recently talking to another and he said he didn't like the WAGO because they score/cut into the wire. I said, other devices certainly do that, but the WAGO was a pinch/squeeze. That changed his mind. I like the WAGO's because of its easy install and clean.

Excellent presentation. I know space heaters running on high generally cause their plugs to be too hot to touch so I only run them on high for a short period of time. If I need more heat, I use multiple heaters on low or medium.

The ONLY disadvantage of Wago is the price of the device. They are in any other respect a far superior splicing device. Also, many have made very sound arguments justifying the price of Wago with their efficiency of installation which saves on labor costs.

Good video, but what was the Voltage drop across the Wago vs the Screw nut at that High currents? That will also give a good idea whats happening too

Excellent video! Really appreciate the quality of your research here. Thank you for doing such a good job collecting data and displaying it.

Used wagons for over 10 years, they are a rated device which limits user error and increases space inside junction boxes Use them within ratings for greatness

This is a really great test! Could you do another video comparing heat from cheap receptacle backstabs vs. screw terminals? Also, I think you should repeat your Wago vs. Wirenut test with multiple splices in series to see if there are compounding effects from increased Wago resistance over the course of an entire electrical circuit. The difference was only a few degrees F with one splice, but does it get dangerous with 6 or 12?

It would be interesting to test this with a continuous load. Like hook up an EV charger pulling 16 amps on the 20 amp outlet (max amp draw for 20 amp outlet for a continuous load) and see how hot a wago gets after 4 hours of continuous load. And then again at 8 or 10 hours. I'm sure it'll be well below the 105 degrees C that they are rated.

I love the honest review and all different perspectives. Very thorough yet to the point..

Great video! Thank you! I thought the only reason folks didn't use more wago's was cost. But I did always wonder about this issue.

Great video. Yeah the WAGO is a bit hotter, but it is still well within design parameters, and perfectly safe. And the ease of use is amazing on the connectors, helping get a better connection and setup.

Old timer engineer here. I was skeptical about Wagos at first. It took me a while to get comfortable with using them. I dismantled one to see if I thought it would hold up over time. I am comfortable that the Wago connector will not fail with age, inside their safe usage parameters. The only thing I still worry about is if anything can catch on the lever, at least on the type with levers. So I am still cautious where I use them. I was up at the end of a 20ft ladder installing a new light in the equipment shed, when I accidentally lost hold of the fixture. I had a Wago on one of the wires and it held. It was a fairly heavy fixture. I was both impressed and happy about not loosing a brand new fixture!

Very convincing test for me, I'm sold to the use of Wago lever nuts anyway. I wish that you could redo the same demonstration using the mix of rigid and stranded wires together because this is where the wire nuts fail the most often and the Wago seems to offer a safer contact. Situation we encounter with electronic thermostats and heating baseboards for higher current than the lighting fixtures.

I would like to see a test done like this with wire nuts and wago’s that have been in service for 5 or so years to see if either of them lose spring tension

Nice. I'll likely use nuts where the load is higher for the added safety as well as added efficiency. Outlets for example. Where load is low like on LED lighting I don't think the nuts have much advantage and will use it there. I'd be interested in seeing a similar test for the new Leviton Wago-like outlets.

The Wago has a current and voltage rating. These are continuous ratings. I have not been able to find any information on surge current ratings. I have no doubt they work as intended within their rating. However, If you use these in a circuit with a bunch of LED fixtures the parallel capacitance that must be charged can be high. I have measured over 200 amps, the maximum on my peak reading meter. This surge is over quickly, but the voltage dropped across the Wago can be 10's of volts. ( Using an oscilloscope to capture the event. ) That is an instantaneous power of over 20 000 watts for a few microseconds. The small contact area will instantly heat and oxidize. It may still carry the normal load for awhile but go through several on off cycles and see what happens. I think the same surge is leading to the high failure rate of wall switch contacts that is becoming common. A properly twisted wire pair and wire nut has enormously more contact area and does not have this failure mode.

I think it all comes down to, what do the manufacturers recommended applications and installation instructions say, a lot of codes rely on what they say. As an engineer I like the simplicity of the Wago connectors in that they give you a quick visual indication as to whether the contacts are closed via the lever, but that is not an indication of a good contact. Overall, it comes down to the person using the device, I have seen extremely scary stuff out in field that was installed by so call pros and things installed by DIYers that would pass the most rigorous checks and tests.

I recently switched from wire nuts to Wago 221. The Wago is much easier to use and reuse. I feel more confident in the Wago than the wire nut. Two thumbs up for Wago.

I think the question is how they will hold up over time. Will the spring lose tension with heating and cooling cycles and gradually increase the resistance of the connection? I installed some on a well pump circuit for a stress test and so far after almost 6 months they are holding up quite well. I've been waiting to do a review video until the results are in but I tend to agree that they may be a good option especially for the DIYer. I'm an electrician by the way with 38 years of experience. I don't like the quick connects connections on devices because of the high failure rate and I though that the WAGO's may have a similar long term result but now I'm not so sure I was correct.

I am licensed home inspector with 50 years of experience and training. After seeing your other videos on Wago connectors, doing some research and using them myself, I recommended Wagos especially for splices combining multi strand and solid conductors. Multi-strand and solid wire splices are the splices most often loose and/or where the multi-strand conductors pull out of the splice. We often inspect houses that are more than 50 years old. NFPA has identified these houses as containing circuits with deteriorated wire insulation and corroded loose splices and terminations. Deteriorated conductor insulation and loose connections create a higher risk of arc faults (a primary cause of electrical fires). insulation and increases the risk of arc faultstral circuits might have different results.

Pre-twisting wires before applying the wire nut is not required nor recommended by the wire nut manufacturers. The manufacturer recommends using the wire nut itself to do the twist by tightening the nut until the wires are twisted. There is absolutely no difference in the finished connection when you remove the wire nut and visually inspect and test for mechanical connection. Also, it is much easier to get all the wires fully inserted into the wire nut if you do NOT pre-twist. Professionals do it, for no good reason. It is not necessary, nor is it recommended.

I like the wagos for lighting circuits, but I still think I prefer the wire nuts for outlets. If you twist a wire in a wago too many times, it can come out.