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Giant

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Everything posted by Giant

  1. The dutch barge crowd largely seem to swear by the cement approach, apparently fine for several years at a time if done right with a few coats. Sticks to the steel like the proverbial, sets very hard, and protects against corrosion because of its alkilinity. We currently have one of ours drained out and debating whether to go for cement or epoxy. The prep for epoxy is daunting in that space...
  2. I think this setup I built is about as "weapons grade" as you can get: The rectangular box in the middle is a RouterBoard RB912 in the BaseBox2 outdoor enclosure. It has a high end 4G modem in the MiniPCI-E slot, with MIMO capability. Its two antenna ports are connected to the antenna on the far left, which is an integrated dual polarisation omnidirectional unit, covering 2G/3G/4G bands. The built-in wifi radio of the router is connected to the pole antenna on the far right. There is gigabit ethernet running down the mast and into the boat, with the router powered by a 24V power-over-ethernet injector. The board is currently running Mikrotik's RouterOS, but is also capable of running OpenWRT. With either, it can be configured to do pretty much anything, but the most obvious function is to share a 4G connection with the rest of the boat (there is a separate wifi router inside). The outdoor wifi capability can be used to either hook in to any nearby access point, or create a new one for use on deck or to share with the neighbours. Probably not that practical but you did ask!
  3. I was once required to use LSZH cable for some kit I was building that was going to be temporarily installed in an aircraft for flight testing. Never heard anyone else asking for it before or since.
  4. At the end of the day, nobody is really going around inspecting boats for RCD compliance other than those employed to do so by their manufacturers. A buyer's surveyor might spot some things they recognise as not being done to the specs, but that's about it. You can compile a technical file and 99.99% of the time nobody will ever read it. About the only scenario it would get looked at is if there was a major accident and big-money lawyers ended up poring over the details in a long court case. And why would they bother? Usually it's cheaper to settle than to get into the details. It's the same with most other products and most other such EU directives. The manufacturer slaps a DoC on it and, supposedly, has a technical file stashed away in case someone wants to check but nobody does. The file may be rigourous or sketchy or not exist at all. You can imagine how it goes. For various things that actually matter, like aviation kit or medical devices, there are "notified bodies" who have to review everything and issue an approval before a CE mark can be applied. For everything else, it's essentially a system of self-regulation where people do as much as they feel like doing to cover their arse, and will almost always get away with it. Personally I take some pleasure in doing things by the book when I design things, but then I have the benefit of people willing to pay me to.
  5. I'd be wary of anyone proposing to simply inspect the boat a couple of times and write up the paperwork. What the paperwork is supposed to show is how the fitout has been designed and built according to the standards. Without becoming familiar with the standards yourself, how can you do the job right in the first place?
  6. That isn't a BSS requirement. I think you're thinking of some standard related to the EU Recreational Craft Directive (RCD).
  7. I saw it done. Here's a clip of the same trick that shows it as a continuous shot: https://www.youtube.com/watch?v=RmOimiKIxDY&t=32
  8. Nope! They would crack it open afterwards to prove it.
  9. In general there are two ways that pumps and things make noise: sound carrying directly and vibration transmitting to the rest of the boat. You can limit the direct transmission of sound by boxing it in and insulating the box. With where it's placed and the foam you've added you may have already achieved that, but if not you may find that plugging the last gaps makes all the difference. Vibration is a matter of the rubber feet, and as you say it may be worth replacing the ones that are there. You can get some amazing anti-vibration mounts these days. I was at a trade fair a few months ago and a manufacturer was showing off the energy-absorbing gel they use for them. You can drop a raw egg onto an inch-thick layer of the stuff from 20m up and it will stop dead without breaking.
  10. Electroquest sell a lot of different chargers from a range of manufacturers. The ones they sell that look like that, with a red casing and black front panel with red LED display and fans, are made by a Taiwanese company called Fairstone - http://www.fairstone.com.tw/english/index.htm I don't see any evidence of testing & certification for them anywhere, and it seems the manual comprises these two pairs of pages. I don't think I would spend that much money on one, whatever its claimed specifications.
  11. I wouldn't want to see IC sockets in a marine environment. You want a solid connection that can't get separated by corrosion.
  12. You won't find one. Unfortunately the good old days are long gone when the schematic was to be found in the back of the manual because it was expected someone might need to repair the product. These days schematics are almost universally closely guarded secrets, shared only with approved repairers if at all. The only way to approach DIY repairs now is usually to work through the PCB trying to identify the functions of things, figuring out what voltages and waveforms should be expected where, and trying to find the first point in the system where things look wrong. When things get complicated, sometimes even drawing out parts of the schematic by tracing out the connections visible on the PCB. In this case, with a two-layer board and lots of easily identifiable through-hole components, that's reasonably doable - but it's still slow work. And hard to do without having a good knowledge of common design patterns and faults, the board powered up in front of you, and an oscilloscope to see what's going on. For multilayer boards covered in unidentifiable SMT components, it can be nigh on impossible. Looking at this one, I'm afraid I don't really have any more obvious ideas for Alan to try. I'd need it sitting in front of me to try and probe through it and understand what's going on.
  13. Here, but we don't have much more to go on than you do - without a schematic or even the PCB to look at, a black box is a black box. Could you post photos of both sides of the PCB? A few thoughts, without sight of the board: Something must have caused that input fuse to blow in the first place. The goal should be to track down what. So first question: is it still blowing fuses? You've replaced the input fuse and powered it up, now take that new fuse out again and check if it's been blown. If the new input fuse has blown, then something is still more-or-less shorting out, and the strategy is to find that low-resistance path. If it hasn't, then something did fail and briefly drew a high current in the process, but has now burned itself out such that it no longer shorts -- but presumably no longer functions either. The strategy then is to identify what blew, either by visual signs of failure (which you've drawn a blank on so far) or by detecting a lack of function. Whatever it is, I would expect it to be within the mains side of the circuit, because a fault on the low voltage side would have to pull at least 3.6kW through the transformer to blow the mains input fuse and you'd expect something else to have obviously gone bang in that case. The most obvious candidate would be an electrolytic capacitor. Often the first things to fail in any electronics, but particularly common on the ones that are exposed to mains voltage, especially if ever exposed to spiky supplies. Look for any signs of bulging in the ends of capacitors.
  14. That will be a battery protection circuit. Generally two MOSFETs and a little IC that monitors voltage and/or current. In normal operation both FETs are on. If the voltage or current go outside set limits, the IC shuts off one or other of the FETs (one for charge, one for discharge). The features vary, but many will cut off for overvoltage (4.3V or so), undervoltage (2.8V or so), overcurrent for charging (a few C), and overcurrent for discharging (many C). These circuits aren't sufficient to ensure a proper charge cycle on their own, and in normal use they should never trigger. They're just a failsafe for if something else goes wrong.
  15. I'm rather worried what the effect of all this widebeam bashing will be on the North East. Lots of old Humber barges being kept going and/or lived on up there, in various beams from about 14'4" to 17'6", on massive broad canals where there's plenty of space, and 600 ton commercial traffic still going by. Switch to area based charging and all those folk are suddenly paying 2-3x their current license fees, for no change in anything. It's not a rich part of the world. Not everything is about the bloody Grand Union. I say this as someone who won't be affected at all, as we're long since off CRT waters.
  16. I've heard it said recently that Euromarine seem willing to insure pretty much anything that floats. I have no actual evidence to support this rumour but might be worth a call.
  17. I have a figure of 250kg in my head for the JP3 bare block weight. We looked it up somewhere when we were getting a quote to repair our cracked one a few years back, but I forget where we found the number.
  18. Thanks for this Safeworks, I'd been on the lookout for a good source of DC rated DIN rail breakers. Link for anyone else looking: https://www.expertelectrical.co.uk/circuit-protection/chint-miniature-circuit-breakers
  19. Giant

    A tale of two JP3s

    Quick question, what are the nominal diameters for the main and crank journals? I want to be sure we have micrometers with enough reach, that I trust the accuracy of. Edit: oops, don't mind me, just found the section of the manual that lists these as 3" each.
  20. Ah sorry, missed that line. Still, worth giving the steel a good scrape/brush down before putting it on. Hammerite is handy stuff but not magic!
  21. I would suggest you clean up the exposed steel before adding any new foam, as it looks like it has gone rusty. Then if you apply sprayfoam it can bond to good steel rather than to a layer of loose surface rust. Or if you decide to cut blocks of solid foam, paint the steel first. Otherwise, you are leaving a space behind the insulation where condensation can form and corrode away the unprotected steel.
  22. Probably still not a bad decision once you've sorted this out. When we bought our boat we found the installed Par Max pump was surrounded by a small graveyard of failed Shurflow ones, it's continued to hold up since.
  23. Also, was the previous pump the same model? If you've not thrown it out and the only problem was it leaking, it's fairly easy to strip it down, clean up the gaskets and reseal. We have the same pump and had to do this a year or two ago, no problems since.
  24. It's probably worth replacing that filter casing anyway, as you need to be able to open it to clean out if it gets gunked up. Once done you can then see if it solves the probem before spending time/money on the pump.
  25. See edited post above, mross (can't give you a post number as the new forum doesn't show them, aaagh!)
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