A Safer Shore Power Connection? Testing the SmartPlug


A few years ago while visiting our friends at Advanced-RV, we learned about a new type of shore power connection they were putting on their rigs, The SmartPlug.  (We like visiting Advanced-RV because they’re always pushing the envelope with cool new stuff.)  The SmartPlug had a few unique features, like easy locking and weather proofing, but what really captured my interest was the claim of reduced connection temperatures and improved safety through increased contact area.

Ever since then, I had been wanting to get a SmartPlug on our own rig.  I finally did, and decided to put the “safer connection” claims to the test.  The result is this video:

 

Here’s the deal.  On their website, SmartPlug includes an infrared photo that plainly shows the SmartPlug operating at a cooler temperature than a “regular” 30 amp connection.  But I had questions about this.  Was the load going through the two plugs the same?  Were both plugs installed properly?  And most importantly, was the regular 30 amp connection plugged in securely and correctly?  Basically, I wanted to know if the SmartPlug marketing department had rigged the test and used a “faulty” connection as its comparison.

 

The Test

Full Disclosure:  There is none!  I paid full retail for my SmartPlug (I just bought it off Amazon.com), and I’ve not contacted the manufacturer in any way as of this writing.

 

The setup for this test was pretty straight forward.  First, I took an infrared reading of the empty and un-used plug.  Then, I simply plugged in the regular connection – making sure to do it properly and make full contact.  After that I ran a load of 24 amps (at 120 volts) through the connection for one hour.  At the end of the hour, I duplicated the SmartPlug infrared photography and took a temperature.

Then, it was time to install the SmartPlug.  I made sure to follow the manufacturer’s instructions on the install.  SmartPlug even provides torque specifications for all of its electrical connections, and you’ll see my small torque wrench in the video.  Once I had both the socket and plug parts of the SmartPlug installed, I repeated the 24-amps-for-one-hour test, and took another infrared video.

The Results

While I couldn’t control for outside temperatures, I did run the test on a cloudy day, and out of direct sunlight.  The temperatures I recorded were:

  • Empty Connection:  22 degrees Celsius / ~72 degrees Fahrenheit
  • Standard RV Connection:  43 degrees Celsius / ~109 degrees Fahrenheit
  • SmartPlug Connection:  28 degrees Celsius / ~82 degrees Fahrenheit

 

So good news!  The SmartPlug did indeed result in cooler connection temperatures.  At least in this test.

Now, I do want to point out that I DON’T think my regular RV connection was faulty, or in any way unsafe.  The temperature of the plug was not dangerous or painful to touch at all, and there was no danger to our rig throughout the test.  But… I knew that my shore power connection was installed properly and with tight contacts.  It’s not too hard to find pictures of burned and blackened shore power connections online.  If you had a compromised shore power connection, the temperature could easily get to an unsafe level.

There are other features of the SmartPlug that, while I didn’t test, I do like.  The plug has locking tabs on each side that are far easier to use than the threaded connection on my old plug – and they simply can’t be cross-threaded.  The SmartPlug also has weather-proofing in several areas that should provide increased confidence in wet environments.  (They also market marine connections, so this makes perfect sense.)

All in all – I can recommend the SmartPlug.  It does seem to provide – at least based on my test – an increased level of safety against connection overheating for your RV shore power.  I’m certainly keeping ours.

Now, if I could just do something about the pedestal end of the connection…

 



James is a former rocket scientist, a USA Cycling certified coach, and lifelong fitness buff. When he's not driving the RV, or modifying the RV (or - that one time - doing both at once), you can find him racing bicycles, or building furniture, or making music. In his spare time, he works for a large IT company.


    14 thoughts on “A Safer Shore Power Connection? Testing the SmartPlug

    1. Graham Smith

      I like the concept and the design but I’m not sure if there is enough gain to make it worth while. They are rather expensive ($140 for the set) and an additional $70 if you need to make an adapter (which I do).

      Reply
      1. James - Post author

        It can get a little spendy; can’t deny that. Might not be for everyone.
        If I had to replace a connection and plug anyway, I would probably replace with a SmartPlug.
        Also, if I had concerns about the connection quality, or I was trying to run a welder through my RV or something… 😉

        Reply
    2. David

      This isn’t about the Smart Plug but about something in the video. I saw you’ve installed a faring on the roof rack on Lance. Have you ever provided instruction as to how you built that?

      Reply
    3. Fred J.

      Does the smart plug have adapters for standard plug interfaces? I would not want to be limited to only the smart plug configuration, if you find yourself without the cord with the smart plug connector, you are out of luck?

      Reply
      1. James - Post author

        I’ve never seen any adapters, and I don’t think SmartPlug makes any. That would sort of defeat the purpose of getting rid of the regular RV-style connection. We always travel with our own shore power cord, so we don’t anticipate it will be a problem.
        I suppose if you were in a situation where you have to “borrow” a cord, you might run in to difficulty. That’s never happened to us. We have needed an extension cord a time or two. That would still work, as the pedestal end of the cord is the same.

        Reply
    4. SkagitStan

      Have a question about the temperature measurement.

      It *looks like* the SmartPlug cord end has an additional (weatherproofing?) shroud around the plug that a 30A Hubble twistlock doesn’t have. That plug just appears to be the barrel that’s inserted into the bulkhead socket.

      If so, could that shroud keep heat buildup away from the outside of the SmartPlug assembly, causing it read a lower external temperature than is actually seen at the power pins contacts…as compared to the twistlock style?

      I’d assume that in either properly functioning plug, heat buildup is largely conducted away by the wire.

      Reply
      1. James - Post author

        The SmartPlug does seem to have more plastic around the contact area, and I agree that this could help shield the camera from seeing any heating, if it occurred.
        That’s why I let the test go for an hour. Even if there was additional material, I surmised everything would have heated through and reached equilibrium with the atmosphere after an hour.
        Measuring temperature at the contacts themselves would have been ideal. But… I was paying for this myself. 😉

        Reply
      1. James - Post author

        I didn’t take the temp of the empty socket after each run. That would have been difficult, as I don’t always nail everything on the first take. To be fair, I would have had to take the video immediately after removing the plug in both cases. C’est la vie.
        “Before” empty socket temperatures were basically ambient. The SmartPlug socket was installed in the van a good hour or so before I got the plug finished and was able to run the test.

        Reply
    5. David

      I’m very familiar with this in the boating world. The secure fitment at the RV is what it is mostly promoted. Boats catch fire frequently from the poor prong fit into the sockets in traditional round connections. Arcing occurs from the loose fit and fires start. So this Smart Plug is a very nice product. I have a round version that attempted to copy some of the Smart Plugs connector benefits but it still isn’t as good as the Smart Plug.

      Reply
    6. Aaron

      Great video. Your findings matched my suspicions that the SmartPlug is an improvement but probably not an essential upgrade for most people.

      Reply

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