How About a New 12 Volt Automotive Connector?

12v automotic plugDon’t get me wrong — I do like standard connectors.  A while back, I wrote about how the micro-USB connector became the standard power/data connector for mobile phones. Well, that is unless you own an iPhone.

The good news is that we do have a standard power connector for 12 VDC in automobiles. The bad news is that it is an ugly behemoth derived from — can you believe it? — a cigarette lighter. For some background and history, see the Wikipedia article. The Society of Automotive Engineers (SAE) has a standard that describes this power connector (SAE J563). Alan K0BG correctly warns us to “never, ever use existing vehicle wiring to power any amateur radio gear” including the 12 volt accessory plug. (I always follow this advice, except in the cases when I don’t.) I also found this piece by Bill W8LV on that describes the crappiness of these connectors.

Well, there is a new standard power connector showing up in cars: the USB port. These ports provide the data and power interface for mobile phones, integrating them into the auto’s audio system. Standard USB ports (USB 1.x or 2.0) have a 5V output that can deliver up to 0.5A, resulting in 2.5W of power. A USB Charging Port can source up to 1.5A at 5V,  for 7.5 W of power. This is not that great for powering even low power (QRP) ham radio equipment.

Now a new standard, USB Power Delivery, is being developed that will source up to 100W of power. The plan is for the interface to negotiate a higher voltage output (up to 20V) with 5A of current. Wow, now that is some serious power. We will have to see if this standard is broadly adopted.

Two things are obvious to me: 1) the old cigarette lighter connector needs to go away and 2) it is not clear what the replacement will be.

What do you think? Any ideas for the next generation of 12V automotive connector?

73, Bob K0NR

The post How About a New 12 Volt Automotive Connector? appeared first on The KØNR Radio Site.

Bob Witte, KØNR, is a regular contributor to and writes from Colorado, USA. Contact him at [email protected].

11 Responses to “How About a New 12 Volt Automotive Connector?”

  • Edward C Schaub W5TUT:

    I would think that some after market company would make a connector to repalce the one installed in the vehicle. I have never taken mine out to look at it but the fuse for it is 20 amps I would have to look at the wiring to see if it is adequate to run a 50w radio.

  • Matt W1MST:

    Great article, Bob!

    One thing that puzzles me is why Apple insists on using something other than micro-USB — their 30-pin and, most recently, 5-pin “Lightning” connectors.

    Phone power cord standardization is such an advantage to consumers that I can’t imagine any advantage of these lesser used schemes that would justify the inconvenience it often causes.

    At my workplace it’s easy to put my hands on the ubiquitous micro-USB. When the iPhone users look for a charger, it always seems to be a process to find the right version.

  • Jason VE3MAL:

    Standard phone power connectors are great -except when the phone’s are DRM’d or otherwise broken to only charge of “compatible” chargers, like my wife’s blackberry.

    The worst thing about cig lighters is when cheap plugs break, and short the connection, blowing the fuse. What a terrible design. USB connections for low power, and powerpoles for high power. I don’t hold out any hope for stock high power connections in cars, so the powerpoles and wiring just have to be added by us.

  • Cai W6CAI:

    Someone ought to make an insert with the same outside dimensions as a cigarette lighter socket but with power pole connectors instead. I’d love to be able to yank out the cigarette lighter sockets in my car and replace them with a clean-looking, dash mounted power pole connector. The cigarette-plug to power pole adapters work alright, but the cigarette lighter connection can be flaky.

    If not a power pole connector, the bullet-pair connectors commonly found on solar equipment would be a reasonable alternative: (example:

  • Mike, WV2ZOW:

    There was an attempt to use a real power connector for 12 volts, but it didn’t seem to catch on. It is the EmPower connector found mostly on commercial airliners. Its round, smaller than a cigarette lighter connector. Rated 15 volts, 75 watts.

  • Stephen G0PQB:

    I read an article in a QST magazine about putting in a power pole connector on to a cigar plug and suggested using a redundant cellphone charger as a starting point. I cannot remember which issue of QST had this article but I would think it would be fairly easy to trace.
    I do use an FT817 through my cigar socket as in my car, a Japanese Daihatsu Sirion- sadly no longer available in Europe, the fuse in that circuit is rated at 10A and the FT817 needs 1.9A at 5 watts output. I only use this set-up when the car is parked up- not when driving.
    Anyway this is an interesting article to follow.

  • Michael. N1VSU:

    I purscased a marine portable and it uses micro usb for charging internal it includeds wall and car charger with usb to micro a new ht should be set up this way especilly with new
    Lithium battery

  • W3FIS, Paul:

    The local hardware store carries 2 pin “bullet” jumpers, about 10″ long. Cutting off one end of the other makes a nice connector. I use one on my SLA gel cells to mate with a charger. When the charger is removed, there is another cable also on the battery — 5.5 x 2.1 mm coax plug for my QRP and other low power stuff. I also have a “go” box to hold the battery with a cigar lighter socket in the lid that can be connected to the bullet connector on the battery. A couple of my power supplies (Samlex, MFJ) have the cigar lighter, so I have cigar lighter to 5.5×2.1 cables as well.

    Not the most satisfactory thing, but moving everything to power poles isn’t going to buy me much. Higher power stuff (Alinco DX-SR-8, and DR=605) are directly wired to the power supplies with ring lugs.

    73 /paul W3FIS

  • Tom KA4CSG:

    In my RV, I did a very clean Power-Pole installation in the window plastic. They go to a fuse block, then directly to the auxiliary (house) battery.
    So nice, it looks as if a factory installed it – that was the stated goal.

  • Joe KB3PHL:

    I’d like the idea of having Power-Poles becoming a standard automotive power connector.

  • KC2WEX:

    Hook it direct. with the exception of the fuse of course.From the wire connector that goes to the device, you can use that to take the device out if necessary. another approach, say you have a transceiver.drill a hole in the dash for a female cigar plug that goes directly to the battery, of course useing an inline fuse.Then the transceiver can contain the male cigar plug and it would be easier to plug in and out a unit instead of the hassle of dangleing wires

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