Paul wrote >I've followed the success (and/or lack of it) of many of >my Auckland paddling buddies as they have used VHFs, GPSs >& cameras with various IP ratings. G'day, I'd agree relying on IP ratings to rate ability to survive exposure to the elements above water is a waste of time. The IP rating as I understand it is for water ingress ie a fixed amount of time at a fixed depth under the water, for that it looks perfectly adequate provided there is an additional specification used for exposure to the elements. McMurdo/Kannad (I don't understand the relationship) focuses on the IP standard for the waterproof ratings on its Kannad range of PLB products and provides references to standards as well as specification sheets. But it doesn't do this for the almost identical Fastfind PLB range. Whats going on here? Anyway I was very impressed by their descriptions of the Kannad PLBs but would still like clarification of whether an appropriate guaranteed expectation for the unit is that it will remain operating for 24 hours attached to a man overboard. All the best, PeterO *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Peter wrote: > relying on IP ratings to rate ability to survive exposure > to the elements above water is a waste of time I first met IP ratings as a young engineer, trying to keep remote flood-warning systems alive on mountaintops. That was a sufficiently real-world experience - and the manufacturer's IP ratings of their protective cabinets was a good place to start. I never had to design equipment for the fore-deck of a destroyer. Being slapped by a big green sea at 40+ knots of boat speed was noted in the 'exposure' tables as being harsher than any fresh-water rain events could ever be. The relationship between static tests for leakage (x minutes at y metres) was/is considered only a starting point for determining the ability to survive dynamic / shock loading by jets of water. That, in sea-kayaking terms, is the big swell surprising you as you paddle out through the surf - smashing into your chest and subjecting you & your gear to a sudden spike of water pressure. Even though you are still more-or-less on the surface, the water pressure experienced by you & the devices on your PFD could be simulated fairly closely by some static depth/duration test. The static test, of course, are very easy for everyone to duplicate - a calibrated wave event is harder. So, although I never plan to spend much time at 10m (33') depth with my PLB, I'm relatively happy that real-world surf events won't subject it to more pressure than it can survive - if it's demonstrated an ability to survive 30 minutes at 10m. If it's only good for 5 minutes, the seals are not as good as they must be for 30. That better rating also indicates a manufacturer willing to over-design a bit from the required standard. I can admire that in a bit of safety gear. I agree that it is disturbing that McMurdo seem to have stuffed up their web pages of specs for the unit. Let's see if that is them backing away from the 210's ratings or just web incompetence. It's interesting that some of the Spot devices had serious issues with independently performed static-test pressures. They didn't leak, but they turned on (SOS transmits) and went into funny modes of operation as a result of the pressure causing spurious button 'pushes'. The Spot 2 recall seems to have addressed this - but resulted in a significantly reduced depth rating (after Spot fitted a GoreTex membrane to relieve the pressures). As kayakers, it seems to me that all of these IP-rated devices - which thereby have some pretensions to surviving in a wet world - probably meet or exceed their ratings 'out of the box'. What is more interesting to us - and seems to be nowhere tested - is their ability to keep doing it in a salty environment. I have few fears that a new PLB (from any manufacturer) will fail within 24-hours of a man-overboard situation. I think the waterproofness of a new unit will survive easily that test of surface-pressure and durability. There can be no significant corrosion or loss of plasticisers (in rubber seals) in 24 hours. I'm more concerned with the Stu Trueman test - 16 months in a salty PFD before use. At what stage does some vital element degrade from UV, salt, damp, mould, whatever. This is the sort of durability & extended exposure test that car makers subject stuff to - as new cars need to last a good few years before they start to leak - otherwise the brand gets a bad name. That, of course, is one of the attractions of a 'brand'. Most PLBs carry a 5 year warranty - so they should last this long - but do they in a kayaking environment? Best Regards Paul Hayward, Auckland, New Zealand *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:33:55 PDT