NavisBD

I don't suppose there is a site anywhere which lists common appliances and their startup loads? It seems to me that 2kw won't be much use! I knew it wouldn't power an electric fire or hairdryer, but thought I'd be ok for a pretty feeble vacuum cleaner - you'll tell me next that my spare 800w microwave ain't gonna work either! It is Pure Sine Wave though

That could be a blow. The vacuum cleaner I have lined up is 1300 watts - I thought 2kw inverter would be ok. Is there a such a big starting load on a vacuum cleaner?

That's EXACTLY what I want! Couldn't find one on eBay

Yes, I must admit 16mm might be a bit light. The cables from the battery bank to the switch unit are 35mm I think, which seems more in line with your thinking.

Yes, but I've got to scrape together the money to get a marine electrician in, since I can't get a definitive answer about whether it needs the earthing terminal connected, and if so how I should do it. The manual (Far East) with the inverter doesn't help, as it only says 'should you need to ground the inverter, attach an earthing strap to a suitable point'. Dead useful! I took some stick on previous posts about this, the clear implication being that if I didn't know exactly what I as doing I'd best leave well alone.... At any rate, it's not top of my priorities at the moment (that is re-routing some appalling pipework). As an aside, I got a 115 watt inverter £9.99 on offer from Aldi a few weeks ago. Plugs into cigar socket and powers the radio/tablet/cooler box fine! Interesting. It only came with 16mm cabling in the box!

I do have a 2kw inverter, not yet plumbed in. no shore line, no genny. Question was more about principle ie whether some ingenious person (and there are many around on this site) who had come up with a technical solution to non-electric vacuum suction which could be adapted. Maybe it's just not physically possible, but I merely raise the question. Battery flat, inverter broken, broken coffee jar scattered to four corners. Sort of thing.

Some good suggestions. The carpet sweeper is ok for flat long surfaces, but that's not really what I had in mind. If you think of those instances in a domestic situation where you'd attach a hose to get at fiddly areas - it's that I want to emulate. I'm not going to buy a 'carvac' type thing again, as I believe it would throw good money after bad. No matter what some reviewers (plants?) say, I've yet to meet one of these devices which has any suction power worth the name. Perhaps the physics makes it impossible to generate powerful suction from 12v, although pumping eg in bilge pumps seems to be able to reach a fair head of steam from 12v. The 'recharge at home, use on boat' is certainly possible eg Dyson, but they are hardly a cheap solution. I've also read some pretty scathing reviews, mainly concentrated on the input/output figures ie hours on charge/minutes of vacuuming. Can any of the users here say hand on heart that the suction power in a rechargeable is comparable to a mains-operated vacuum cleaner? If so, I might look further into replacing our domestic hoover, with the wife's agreement!

This one's a bit left-field, as my kids would say, but bear with me. At the moment my boat is completely off-grid. The one thing I miss above all is a vacuum cleaner! I'm yet to find a 12v dc vacuum cleaner which is worth buying. I've had two, and they were both so useless that I ended up binning them. I know I could run an ac one off an inverter, but I was wondering if one of the miracle inventers on this site has come up with a design for a completely manual vacuum cleaner? It may be that such a thing is impossible, but I'll never know till I ask! Mind you, I only found out recently that there was such a thing as a fridge which could be run off gas, so what do I know?

Lots of food for thought, guys. Don't fall out over it though! My conclusion is that it is worth consideration, but it won't be easy........

Thanks Tony, Yes, 90 degree bends are available but they are quite bulky. Working in a confined space, I want to get both hot and cold pipes to run as closely together as possible - once you introduce couplers the distance between the pipes gets quite large, as well as looking awful. This is an example what I'm working with, and illustrates what I mean about corner couplings ruining the line.

Tony, This is the heart of the matter for me though - I am confident it can be done, so I am interested in why nobody seems to do it. Why are you not sure you'd want to?

I have to do a considerable amount of rerouting the pipework on my 'project', because the previous owner had left all the pipework visible and also taking some crazy routes. I don't wish to visit the merits of plastic v copper pipe; at the moment I have an open mind. However, I am interested to hear people's views on bending plastic pipes. Youtube is full of demonstrations of how, using for example heated sand, plastic piping can be gently curved to a rigid and unkinked 45/90 degree angle. But orthodox plumbing guides always seem to recommend using coupling joints, despite the fact that these are quite bulky and visibly ruin the line. I can only assume that there are good physical reasons for always going with couplings rather than bending, but I don't know what they are. Have any members successfully bent plastic pipe instead of using a coupling?

Yes, that is my unspoken fear. But I presume if so it must be fairly high up in the tank, because once a certain amount of water has been drained from the tank there is still apparently plenty of water in it, but the rear bilge is bone dry.

Sorry to bump this old thread.The boat I'm restoring gives me the same problem re bilge access - ie there isn't any. However, my slightly o/t question is regarding the water tank. I know roughly where it is, because I can see where the onboard extractor water pipe goes into the floorboard. I suspect there is no tank as such, merely a compartmentalised part of the hull. I also surmise that there is no lid to it, because I can fill it forever, and after about half an hour's filling at a BW water point, there is quite a bit of new water in the bilge at the rear of the boat. After I've opened the taps (for a long time!) and also pumped out the rear bilge everything is dry again. I was wondering if any of the wonderful DIYers on the site have come up with getting a rough estimate of how much water there is in the tank at any given point? I appreciate this is rather difficult without knowing the tank's dimensions! My compromise at the moment has been to buy a flowmeter and fit it on the end of the water hose when filling the tank. At least then I know that as long as I stop filling after x gallons have gone in, the rear bilge shouldn't flood again. But obviously this means I may be filling it more frequently than I really need to.

Thanks Keith.

Never realised this subject was so damned complicated! House wiring is a p of p compared to this - get the book, follow the wiring diagram, how to test if the socket is on the ring or on a spur, how to wire up a double pole switch, don't spur from a spur, red flag the live neutral, earth any socket with metal casing etc etc. No ambiguity, no if buts or maybes! Any search on google produces tens of thousands of hits on the subject of inverter bonding and grounding, almost all of which contain some element of 'with the exception of....' Still, some boat electrician somewhere will benefit from my trepidation!

Sorry, didn't mean to return to this but I just spotted the following on a site for a company called Midsummer Energy: "If your inverter has an earthing point [which it has - Navisbd], connect this to a suitable earth with heavy gauge wire, preferably 2.5 square mm. On a steel-hulled boat, a suitable earth is any substantial bolt or stud on the hull/engine [my italics - Navisbd] that is close to but not touching the point where the DC negative meets the hull/engine." My inverter has four connection points (2 red 2 black) and an earthing point. The instructions with the inverter tell me to - logically enough - connect the red leads to the battery positive and the black leads to the battery negative, but no instructions re the earth. The above section from the Midsummer Energy site would suggest that I could earth to the bolt connecting the engine to the hull as long as I have ensured continuity between that bolt and the hull. No? Don't worry, the comments have sufficiently worried me to arrange to get it done professionally. But I shall be a little hurt if it turns out that the professional wires it up thusly. Also is there any Standards Body (ie similar for CORGI for gas fitters) for boating electricians? I have a number of cards which I picked up on a recent trip round a couple of marinas, but none of them quote any trade body initials of any kind.

Sigh. It's a pity that there is no consistency here other than 'get a man in'. I can't understand why something as basic as this shouldn't be a matter of connect x to y and z, or why there seem to be different inverter mechanics. Still, I shall probably employ a specialist. Thanks for all replies.

Does all this mean that a type 1 (if such is my model) needs no separate earth (although there is an earth connector on the inverter)? It only came with Live and Neutral cables. Can I now connect it up to the live and neutral terminals of my leisure battery and good to go? The common neutral in my boat is connected to the engine block, which I assume - but haven't verified for continuity - is bonded to the hull.

So which type would I use for an earthed appliance (ie three core flex, not double insulated)? An inverter which can only be used for double-insulated equipment would not seem to be particularly useful. What if there is an rcd between the inverter ac outlet and the earthed appliance plug?

I have recently purchased a Sunshine/RoHS 2000w inverter. I've never used an inverter before, so: (1) Has anyone on the Board got/used one of this particular model? I can't immediately find any reviews (2) Any useful tips? Although new to inverters, I am reasonably confident on general electrics, and will not overload it! However, any guidance on the topics of earthing/interaction with shorelines/anodes would be extremely helpful. Brian

"Relax" is "relay", sorry if writing isn't too clear. The diagram is correct as far as the battery terminal connections are concerned, though obviously the rat's nest behind the instrument panel is another matter altogether! There is (at the moment) no inverter fitted, although I do intend to fit one. Ditto no solar panel/fan trickle chargers. What else might be connected to the battery bank? Any information gratefully received.

Thanks guys. Really helpful.

The above is a schematic of the wiring around my batteries. I am no spark, but would like to understand what's going on. Firstly, should the leads on the leisure batteries at positive terminals A and B (which are currently black but red-flagged) actually simply be red HT but the previous owner had run out of thick red cable? Whenever I've come across red-flagged neutral in domestic wiring it has meant that the neutral is live in a switching circuit. But I can't see why that would be the case here. Any other comments on this configuration welcomed.

Yes, I thought that! I am rather attached to my hand......