Dometic IBEX 2011, BVFD & WhisperFan


Winter will not be slow on Panbo largely because I still have lots to cover from my summer cruising and fall travels, and more time to do it in. At IBEX, for instance, I learned about a couple of neat ways that Dometic is using sophisticated modern electronic controls to make existing marine appliances work better. And I even got a little (goofy) face time in a video about the Bypassable Variable Frequency Drive (select HD at your own risk)…

If you watch the video you may be as impressed as I was that Dometic has a Director of Technology as articulate as Matteo Giovanetti. The BVFD (product page here) is not that easy to understand, starting with the fact that it’s a fix of a fix. Apparently lots of large yachts already have Variable Frequency Drives to tame the wicked startup power demands of large air conditioning compressors — like the 5 to 25 horsepower variety — but the VFDs can cause all sorts of RFI problems on the boat and even around a marina as they change AC power to DC and back again. The Bypassable VFD, as further illustrated in this video with Flash animations, manages to take the VFD completely out of the circuit once it’s completed its ramping up duties. And hence it can be used with more than one large compressor system, if you have a yacht that big…


While the BVFD seems to be high-end big-boat technology, I’m pleased to know that serious power loads can be handled so precisely with silicon and software. Boats of many sizes would benefit from improvements in power efficiency and noise — both the audible and interference kinds — and maybe some of the wow in the BVFD could help eventually.
   Meanwhile Dometic also introduced the WhisperFan Controller, which uses
“pulse width modulation to make any AC-driven fan as quiet as a DC-driven fanpulse width modulation to make any AC-driven fan as quiet as a DC-driven fan.” It should also increase the life of the fan and it can be used to calibrate low/med/high settings to speeds that actually mean something once the air has wound itself through a specific amount of ducting. Apparently WhisperFan is compatible with most 208-240VAC/50-60Hz Cruisair and Marine Air cabin controls now, with a model for 115VAC/60Hz blower motors coming soon. This time my friend Ed Sherman got to do the IBEX video with the good Mr. Giovanetti.


Ben Ellison

Ben Ellison

Panbo editor, publisher & chief bottlewasher from 4/2005 until 8/2018, and now pleased to have Ben Stein as a very able publisher, webmaster, and editing colleague. Please don't regard him as an "expert"; he's getting quite old and thinks that "fadiddling fumble-putz" is a more accurate description.

3 Responses

  1. Waterfrontchat says:

    Great insights on these 2 new Dometic products. By the way, the Bypassable VFD was honored with a nomination for a 2011 DAME design award at the Marine Equipment Trade Show (METS) in Amsterdam.

  2. Thank you very much for the kind words, Ben. This is a great article as you hit on all the key points and provided great links to our joint “goofy face time”! IBEX is a key trade show for us at Dometic Marine, and everyone looks forward to launching all of our new products after a lot of hard work by the entire staff. We greatly appreciate people like you and Ed Sherman who take the time to seek out and understand our new products, and we’re always happy to tell you and our customers all about them. Thank you again for doing the same on our behalf.

  3. Anonymous says:

    Ben: I think the BVSD is of use to almost any vessel with air-con, not just larger craft. Apart from addressing the RF noise issue, it still has the surge-eliminating technology of Dometic’s single-compressor SmartStart units…but the BVSD is able to deal with up to 4 air-con compressors. For smaller vessels with 1-4 a/c units, the surge elimination allows re-sizing of gensets. In my own case, I was able to drop from a 15kva to a 9kva genset, with considerable savings in cost, weight, fuel use, noise and mtc by using multiple SmartStarts. The BVSD, had it been available, would have done the job better, cheaper.

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