wakey_wake
Member-
Posts
153 -
Joined
-
Last visited
Profile Information
-
Gender
Male
-
Location
Cambridgeshire
-
Boat Name
tba
-
Boat Location
Great Ouse
Recent Profile Visitors
996 profile views
wakey_wake's Achievements
Collaborator (5/12)
11
Reputation
-
wakey_wake started following HIN , Got my new 12V DC connectors - well ahead of the cigar lighter options , Dogs on narrowboats. I'd like to speak to someone. and 7 others
-
Dogs on narrowboats. I'd like to speak to someone.
wakey_wake replied to Sloughwriter's topic in History & Heritage
Yes, their webserver's SSL certificate isn't properly set up. This works without warning, https://cockeyed.com/pranks/imposter/imposter.html (I removed the www. after examining the cert) We weren't going to send any bank details there anyway. 😉 -
Dogs on narrowboats. I'd like to speak to someone.
wakey_wake replied to Sloughwriter's topic in History & Heritage
I don't have a view on this, it's not my picture and I'm not wanting to fire flak. However one of the responses to this "theft" is for the owner and provider of the image to replace it with something else. Often deliberately offensive. In such a case would you consider yourself in breach of the forum terms, for posting something offensive? Hmm, can't find the funny article I remember. Here's the serious version. https://altlab.com/hotlinking/ Ah, huffpost https://www.theguardian.com/media/2015/oct/28/cartoonist-the-oatmeal-trolls-huffpo-over-images-published-sans-permission List of examples of more famous responses https://tvtropes.org/pmwiki/pmwiki.php/Main/HotlinkedImageSwitch Ah here we are! https://www.cockeyed.com/pranks/imposter/imposter.html -
Yes, there's no standard and most of the options have problems. Mine came with a couple of cigarette lighter sockets and a fair fitout of W4 sockets. The cig lighter is IMO a horrible plug. It has minimal wiggle-out protection and so it's prone to come loose, then it can just switch off or worse overheat at the slack contact. We don't use the hot element (actual cig lighter) part any more, so why use the rest of the form factor? Thanks for the links to better quality ones - another thread - I'm just happier without them. The W4 isn't bad, and can carry more current. Mine claim to be rated for 10A, and when new they're probably good for that. The springs can get loose over time and then maybe they'll overheat at 10A also? I would rather not find out because nothing in the design prevents an overheat running away to fire. Also I didn't want to set out out with a whole new kit of four-ways and extension cables in a new standard. Anyway is it practical to draw more than 5A on a 12V socket. a) I have very few devices that would try, and b) unless the cable was chosen with that in mind then voltage drop stop a heavy-current device working properly. Therefore I concluded that the assortment of lower power 12V devices I have can run off 2.1mm barrel connectors, for which the CCTV industry provides cheap connectors. Be sure to have a insulated tip on the inner positive, and if buying pigtail connectors check the cable size - some are really thin cheap junk. The USB PD standard is quite flexible in this respect, and I considered something similar. You can also get "USB PD spoof" boards which will request that the USB PD socket provide 5V, 9V, 12V or various levels between. These could be useful for other kit, but you would need to ensure it remembers the correct setting. However each socket will have an idle current draw, which might be insignificant in your power budget but it bugs me; and you can't (in some cases shouldn't) put a splitter after the USB PD output, because the devices may want different voltages, so it makes sense to over-supply with USB sockets.
-
12v power setup for new TV/Roku....
wakey_wake replied to robtheplod's topic in Boat Building & Maintenance
The important thing to remember is that "12V" input is not 12.000V input but 12±something volts. This applies to what devices expect, and also to what you give them. Kit specified to deal with automotive power has to cope with a quite wide range of voltage on the "12V" input. Cheaper kit won't cope, and non-automotive kit won't be trying. Most kit will have voltage stabilisers of one sort or another. Putting the final voltage regulation in the wall-wart leaves the circuits vulnerable to voltage droop in the (probably thin) DC supply cable and dirt on the DC plugs. Increasingly devices will run on 3.3V or 5V internally, but need most still need more power than can be supplied on a simple USB input (10W at best). What you don't know is the tolerance of the 12V to 5V buck converter design to out-of-spec voltage. The simplest failure is when the input voltage is too high - possibly a resistor overheats, but more likely some silicon gets damaged. There may or may not be a cascading failure. Not knowing the design, it's quite hard to guess what over-voltage will do damage... but there are probably several volts of headroom because many DC buck converters expecting 12V will take 15~20V. Failures from voltage being too low are most likely to be a brownout, i.e. device stops or crashes until power recovers, but the constant-power/over-current one below is more serious. My 4G router has an internal DC to DC (buck) converter to make its lower voltage supplies, 5 or 3.3 or whatever. I forgot the details, and forgot what its minimum input voltage is. I gave it a domestic 12V feed through three 1N4001 diodes, just for each to drop about 0.6v. I'm hoping that I bought enough headroom against over-voltage... OK so far. Having the sensitive kit on a different long copper run from the battery should improve protection from inductive spikes. I don't think you'll get 120W at the wrong end of 100ft of copper wire. If you had 12.2V at the battery and started drawing 10A, you will probably lose a couple of volts in the cable (depending on thickness / I haven't done the numbers for my cable). Now if you still want 120W then at 10.6V in you need to draw 11A and the voltage drops some more. My interpretation is that you're trying to draw constant power down that long cable run. As above, once the voltage drops far enough you're into losing too much in the cable to supply the device needs. Once the voltage drops, the 8~40 to 12 regulator has to "suck" harder to meet the power demand and you're dropping 4V from the battery to regulator. This all points to using 24V supply. There are inefficiencies but you can draw 4x the power before it collapses. There is also risk of applying 24V to 12V kit 💥 and also you may want a second DC connector, physically incompatible with 12V. For the telly setup, it may be simplest to have domestic -> breaker -> 12V-to-24V-boost -> long copper -> 24V-to-12V regulator (as in the OP) -> panel of 12V sockets. Those 12V sockets are then well regulated even at heavier current. You may want local fuses to protect downstream wire. You lose probably 0.5 watts of idle power and another 20% of delivered power. These can be measured so you can decide whether to bother isolating the thing when not using it. (Am I promoting overkill? Not sure) With that 8~40V input regulator, beware that the "12V" output might be a negative, i.e. output black wire at -12V relative to the hull. It depends on the converter topology. -
Too many volts through my water pump?
wakey_wake replied to captain flint's topic in Boat Building & Maintenance
I think it's possible, but bizarrely esoteric. Baseplate. Steel up-stand welded to that, of sufficient height. Pump mounted onto that with acoustic isolation. Then the whole mess thermally insulated. 🤷♂️ -
OK I'm a bit late to the parity, but this reaction might even things up a bit Various youtubbers do these reaction vids. This voice coach's series of them is great. 💖
-
Too many volts through my water pump?
wakey_wake replied to captain flint's topic in Boat Building & Maintenance
With a Jabsco Par-max mounted near its temporary 25 litre Jerry source and 1/3 of the way up, it will self-prime by pumping the air, provided the output pressure is low enough. I suspect it's a diaphragm pump with duckbill valves. This makes two options: usually I can switch the source Jerry without introducing much air, or if the pump is struggling with the air bubble then I leave a tap open until it copes. It isn't a problem, and I don't think a meter's head (= 1/20 of the output pressure) would make a difference on the input. However, I like this and think I will at some point move mine upwards. Murphy's law says any leak will be when I'm absent for a while. Sure it could leak either side, but on the pressure side either you're there to deal with it or the pump is off and the extent of the leak is the pressurised volume. On the tank side, a slow leak draining the tank into the boat while I'm away seems like a semi-trashed boat; less trashed than a fire or sinking, but bad enough. The alarm is a useful component but when you're away, even if it sends SMS / email, what can you do? Containment might be large enough to hold the pressurised volume when the pump is off. It won't hold the entire tank. It would make sense for the alarm to switch off the power to the pump in any circumstances, but this is starting to sound quite custom. (Leaks can spring in other places than the pump, but I'm hearing that this is the more frequent failure point.) Also important to consider! Variations are routine draining, which can be done for some pumps by running dry into open taps - for short bursts and in accordance with the instructions - to help purge the water. Having a valve to admit air or alternate water source could be helpful, and this is essentially what I have and will maintain after reclaiming the bow tank. Or include it in the heating (cabin heating, trace heating) and check the budgets for that or mount it on a metal bracket standing from the baseplate, all thermally insulated. This might be overkill 😛 but perhaps worth considering for a new install? Mine is currently in an under-step cubby, over the base (OSB floorboard between) and against the side of the main water tank (steel bulkhead plus OSB). It's protected by heat of deeper water plus plenty of thermal mass. In moving it up, it would still be in a cupboard. I suspect this will stay close to baseplate temperature, so that's another thing to watch in the cold snaps. They've always worked for me. Two layers of protection is better than one. On a related point, do folks recommend to leave the system pressurised? When I leave the boat I let the pump run, then isolate its 12V. The pipes remain pressurised. When I return it's almost always held the pressure, even after weeks of absence, so I'm fairly sure there are no slow leaks. -
Somehow both amazing and really not surprising at all. 😕
-
That's important to know! Are you able to tell us how you found out?
-
An interesting possible failure mode! I've not looked at alternator current on an oscilloscope, but since it's full wave rectified three phase then presumably one should see six overlapping half-sine peaks per alternator turn? About 1800 per second, if 1200 engine rpm * 2.5 pulley ratio * 6 peaks? (I don't expect most folk diagnosing charging problems will want to bring an oscilloscope into the mix, but mine is just up the gangway. An exercise for later.) ~~ post join? ~~ I do look rather quizzically at some of these shunts I got. The smaller ones are on a plastic base plate, and if that melts the next stop is ground. For a high-side shunt that's Bad News aka. let's see if the fuse works. However I don't see any shunts on ceramic isolation, so I got some bare ones and will sort something. OK the shunt should be protected by the fuse, as it is essentially part of the cable, but it's just a "deliberate" resistor as opposed to an "accidental / inevitable" resistor like the rest of the cable.
-
Ha if you'd carried on digging, you might have had enough gold to last the rest of your life! 💥 If it's the NI credits y'all are talking about, those can be purchased. They have to be purchased because they're worth money later, so... how is getting the credit (stamped card) for free now any different from having a penny out of the social pot which is then saved for your state pension?
-
Sounds like a thermostat problem? My gas oven is like that, it can reach cooking temperature eventually... but not when it has food inside. I think it's running on the pilot lights and just not switching on the main flow for the burner? It's old and I forgot the brand. Probably not worth fixing. I call it a cupboard and cook most things in the frying pan. 🤷♂️ Bread machines are good, I've had several over time but not just now. They'll want 1000 or 2000 watts when they start the cooking phase so 240V only. And you can't cook much else in them, so I think there's not enough space for one in my galley. 😞
-
We're hearing the social approaches, and how they don't suit everyone for various reasons. We're hearing the legal approach, which basically doesn't work at all? There are the technical or internal responses of being somewhere else, or finding a way to cope with how things are. I propose another technical solution of the form "my generator / solar / battery bank <delete as appropriate> is quieter than yours and large enough to supply both of us. How about I run you a shoreline and you can take up to 500 watts to a total of 2 kW hour, and you switch your generator off? And if you take more than two amps it's going to blow the fuse and I won't want to replace it until 9am tomorrow." It will need safety considerations, and probably has other problems. Is it new? Has anyone every done it?
-
That's useful to know for tube heaters. However the more focussed the heating, and better insulated the protected stuff, and the better the control of switching the heat, the less energy you'll need over the whole cold spell. On a shoreline that's "how much does it cost me", but if anyone were thinking of doing it from batteries then it's a critical part of "for how many hours of cold spell could my system sustain this, and what's going to refill the battery after?" Oh yes. On the other hand, an intermittent shore line (such as caused by RCCD trips and somebody coming along later to reset it) may be adequate, as long as the temperature set points have enough space. Stuff doesn't freeze instantly. Not wishing to knock the usefulness of these devices but - on the positioning of temperature sensors: Having observed a gaggle of (cheap) digital thermometers both interactively and with min/max after a period of absence from the boat, I would caution that "the temperature" is a concept which could mislead. You will see the temperature at a particular point, plus or minus some imprecision. Although heat will flow from the warmer place to the colder, this doesn't always happen very quickly compared to whatever else is changing the temperature (weather up top, the drink down below). The temperature at points some distance away will differ. If you measure too far from the thing you're protecting then you risk under- or over- protection which are both more expensive than you wanted, in different ways. 😐 I expect that if the boat is out of water then things will likely be more uniform - and colder. However in the water, I've seen cold spots at the top of the cabin (where intuition says heat will rise to) and warmer down in the cupboards and just above the floor board, where my water pipes are boxed in. Yes, I have a Huawei 4G (5G?) router running off domestic 12V. It's on all the time and has to be factored into the power budget as such. It'll take less to run than an inverter on standby or running low-power 240V stuff. I would think that if the 12V always-on power budget is tight then having a small number of multi-function devices would be sensible. Modern microcontrollers are remarkably efficient, but that's not a reason to run a dozen of them each with their own 12V to 3.3V power supply.
-
Table salt gone soggy again. Frozen olive oil.
wakey_wake replied to wakey_wake's topic in Living Afloat
That would do it, but probably it would also do me. In. This chap is (ironically) lamenting how difficult it is to get the stuff, I've given it a dose of fan heater and also quite a while behind the desiccant dehumidifier. It sounds much better and sprinkles properly again, so I've wrapped in parcel tape. If it goes again, the answer is not buy another cardboard container.- 43 replies
-
- humidity
- galley cabinets
-
(and 3 more)
Tagged with: