Actisense QPD & A2K, more good choices in NMEA 2000 cabling

Ben Ellison

Ben Ellison

Panbo editor, publisher & chief bottlewasher from 4/2005 until 8/2018, and now excited to have Ben Stein as very able publisher, webmaster, and editing colleague. Panbo is going to the next level in 2019 and beyond.

18 Responses

  1. So much blather, and I still didn’t explain the last photo. The tees and terminal resistors left to right: the new Actisense A2K, the Molex that Maretron used to sell, the Escha that Maretron sells now (they like fastening down the cable rather than the tee), the LTW that Furuno sells, and finally the non-metallic gear sold by Garmin and Lowrance.

  2. Ben,
    you should compare 3 Tees and 2 terminator block lenght in all of those versions pictured at the end, as a space occupying comparsion for backbone… Also, pin position inside the connector that define angle between tees of different manufacturers should be compared too, to see what possible complications are when combining tee brands 🙂

  3. Richard C says:

    There is one problem when mixing N2K “T” connectors. Each manufacturer locates the keyway at a different point on the connector. This results in the drop cable either sticking out or angled against the bulkhead. It’s amazing how something as simple as this can ruin the look of an otherwise clean install. I guess NMEA never specified where the keyway was to be placed when setting the specifications for the connectors. My solution to this is to just use a multiport box whenever possible.
    Also, It is very easy, if you are not extremely careful, to cross thread a metal Maretron connector to the plastic Garmin thread on the back of the chartplotter. Anytime you mix metal threads with plastic it can be a serious problem. If you cross thread you will not have a tight connection or a waterproof one. I wish Garmin would change to all metal threads for N2k on the back of their products. Garmin – Go ahead and charge me the $5 additional and use the improved metal connector as a marketing point.

  4. Mike says:

    I suspect the metal retaining ring in a marine environment represent a corrosion opportunity. having a cable connector seized to the body connector on an expensive device would provoke an owner’s ire.
    given that the metal in the connectors i’ve looked at are plated, the situation could be exacerbated by dissimilar metals which get in contact when the plating wears on a thread surface.
    another advantage of composite connectors is they are both more resistant to some kinds of damage that would permanently deform a metal fitting (they flex and then return to shape) but they also tend to have some “self-lubrication” ability and are much less likely to gall threads, not to mention less expensive to manufacture.
    this debate has raged since the glass-filled composite versions of the (in)famous 39999 “mil-spec” connectors first appeared. there are places where metal connector parts are the gold standard, but the cost difference is large (less so in the DeviceNet case i would think), and the operational advantages are not trivial.
    i would be more concerned about the construction of the pins, pin plating, over-molding and the quality of the seal protecting the pins than the construction of the retaining ring. if the pin plating is only good for 5 insertions or the body doesn’t really seal, the retaining ring is not your most important problem.
    -mo

  5. Mike, Those gray Maretron/Molex tees in the last photo have been in use since 2005 ( http://goo.gl/su3Gs ), probably on three different boats and in many network configurations. I’ve never seen any corrosion issues with them, aside from the slight exterior discoloration, or any other metal connectors. I think that the DeviceNet cable and connector standards that NMEA uses are pretty rigorous. You can order the standard here, though like many standards on the industrial side it’s not inexpensive: http://goo.gl/ausWr
    I think all the cable/connector families seen above — Lowrance excepted — are approved by NMEA to the DeviceNet spec.

  6. DeviceNet does seem to lack a standard placement for where the keyway goes relative to the body of a Micro tee, and it seems uncanny how every manufacturer chose a different angle. I’ve yet to find ANY two dissimilar tees that lie flat when screwed together! But different tees can be used OK when separated by cable sections.

  7. I should have mentioned that Maretron’s free N2KBuilder is a great software tool for designing and documenting NMEA 2000 networks. It’s just gotten better since I wrote about — http://goo.gl/l102o — and it can definitely be used with non-Maretron devices.

  8. Henning says:

    Not mentioned in the entry are the small Actisense power tees, similar in size to the tee-connectors. These are unique (I think) in that they don’t change gender. They are like a normal tee and different from the Maretron/Escha tees that change gender.
    I think this is a big difference for those who want to power different groups of devices on the bus independently. Having two or more yellow Maretron/Escha tees in one backbone requires a gender changer (which Maretron doesn’t sell AFAIK) or home made gender changer consisting of a connector cable with one connector cut off and replaced with a field attachable connector.
    A big thanks to Actisense for this product!

  9. Robert says:

    I have set up my network, in the frankenstien manner. the field connectors are a gift to making things work. i had a Raymarine st60 network that i wanted to continue using untill thier eventual replacement. i also had a old Furuno GP30 GPS unit that needed to be used, untill i had something better. this was all hooked up to a new B&G Zues 12″ display, and simrad autopilot, via a maretron backbone. the diffrent connections of the diffrent systems was incredibly confusing and frustrating at first when i was trying to get everything working. then i found out i could use a regular premade cable with proprietary connectors, cut it, and use a ield connector to connect to the backbone. this worked like a charm. i used the raymarine Seatalk to SeatalkNG converter as a multiport. i use the QNB-1 to power the network and reduce the number of connectors needed. everything has worked perfectly, with little frustration. i used good shrinktube to protect the field connectors. i have the information from my ST60’s running on my zues. eventually i will replace them, but for now i can concentrate on more important and expensive stuff/projects.

  10. Anonymous says:

    Ben,
    You didn’t mention it but Furuno has an NMEA2000 Certified, Six Port Junction Box called the FI5002. It features hard-wired, color coded, removable plugs for easy wiring of each of the six drop ports. Plus it also has two larger ports which allows a mini or micro backbone pass-thru. It also has a Power Injector port and two integrated termination resistors, where one or both can be enabled.
    The FI-5002 is designed to simplify installations and save money by splitting cables and reducing a vessel’s NMEA2000 Hard Component count.
    Here is a link to an example of how it could be used in a typical NMEA2000 Installation:
    http://www.furunousa.com/ProductDocuments/FI50DSW%20-%20Depth,%20Speed,%20Wind%20Package.pdf
    And, here is the link to the FI-5002 on the Furuno www site:
    http://www.furunousa.com/Products/ProductDetail.aspx?product=FI5002&category=Parts
    Furuno Tech

  11. The Furuno N2K junction box is covered in the same link with QNB box. It’s super easy to wire and very versatile if waterproofness is not a concern: http://goo.gl/SqE75

  12. michael says:

    The link through to the Molex Brad DeviceNet quadruple Tee does not display this product.
    In searching the Molex website I can’t find a reference to this product or part number under the “Molex Brad DeviceNet quadruple Tee” name.
    Any help with supplying a link that works or a distributer (US, UK or AUS) would be much appreciated!

  13. Sorry, Michael, I couldn’t find a specific product link either, which is why I used the general Molex Brad link. That’s one problem with trying to source DeviceNet parts from big industrial companies. I’m even sorrier that I’m not sure which marine electronics company gave me that sample. But it might have been Gemeco, which carries many NMEA 2000 lines. Unfortunately they don’t show much online and they prefer to work with dealer/installers, but, that said, this still might be your best lead:
    http://www.gemeco.com/index.htm

  14. norse says:

    The 4 port Tee looks like an LTW product (LTWE-555555-FFFFFM-S001)
    http://www.ltw-tech.com/product/product.php?la=en-us&ps=4&pc=18&pd=1835

  15. Interesting find, Norse, but I think that’s a knock-off. The one in my photograph definitely has a Molex imprint and I’ll bet it’s better speced than the LTW equivalent.

  16. Looks like Actisense’s N2K Quick Power Drops are now shipping: http://goo.gl/wqGQU
    They also have a version of the NGW-1 preconfigured to bridge 0183 AIS data onto NMEA 2000: http://goo.gl/qRJVc
    (I think this can also be done with a firmware update, but in either case it may limit what other data can be bridged.)

  17. Gender changer! No, this is not a spam comment. I learned today that Actisense just introduced short gender changing NMEA 2000 cables:
    http://www.actisense.com/products/nmea-2000-network/gc-gender-changer-cable-assemblies.html
    The suggested retail price is about $24, which means they’re close to the cost of a field attachable connector, plus a whole lot faster.
    Needing a gender change while installing or adding to an N2K backbone is a fairly common problem, and I’ve also had it come up in some of the more creative multi-port drops I’ve created 😉

  18. Anonymous says:

    http://www.molex.com/molex/products/datasheet.jsp?part=active/0845870001_DISTRIBUTION_BOXES.xml
    Picture is wrong but if you click on the Sales Drawing PDF you will see the tech drawing with the correct part.
    I spoke with someone at Molex who put me onto the correct part number.
    Thanks for the lead in finding the part.

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