manxmike Posted November 16, 2021 Report Share Posted November 16, 2021 8 hours ago, Tacet said: Petrol-paraffin engines were reasonably common at one time on boats. Cressy was converted and, for a short time, we had a Morris Vedette engine. You had to remember to switch back Just before he went off to defeat Hitler in WW2 my dad used to run an Austin 7. He would fill the float chamber on the carb with petrol to start, the fuel tank had paraffin. Apparently it ran fine, just lots of white smoke from the exhaust. I'm sure Greta Thunderberg would have lots to scream and gibber about if we tried that today. Link to comment Share on other sites More sharing options...
Tacet Posted November 16, 2021 Report Share Posted November 16, 2021 20 minutes ago, manxmike said: Just before he went off to defeat Hitler in WW2 my dad used to run an Austin 7. He would fill the float chamber on the carb with petrol to start, the fuel tank had paraffin. Apparently it ran fine, just lots of white smoke from the exhaust. I'm sure Greta Thunderberg would have lots to scream and gibber about if we tried that today. To my recollection, which is rather later than WW2, that was pretty much how petrol-paraffin engines worked generally. The high-tech approach was two tanks and a couple of valves to allow a choice of petrol or paraffin. If you stopped the engine on paraffin, you would need to empty the float chamber and, if separate, the bowl of the carb. Mostly ended up in the bilge, of course but as it was paraffin, not quite so scary as petrol. In Narrowboat, Rolt mentions fitting a vaporiser to his Model T, which must have been really posh. A quick Google finds https://en.wikipedia.org/wiki/Petrol-paraffin_engine#/media/File:Manly_1919_Fig_133_Fordson_intake.png It looks as though a special paraffin carb ejects an atomised spray which is heated and vapourised by passing through a coiled pipe in the exhaust manifold. Not sure how the speed of the engine was regulated. A separate, simple carb supplies petrol via an un-heated route - but again, how that is regulated? Maybe that engine had a governor controlling a hit-and-miss inlet valve? Elsewhere, it looks as though other vaporisers did little more than use the exhaust manifold to heat the inlet manifold. Link to comment Share on other sites More sharing options...
cuthound Posted November 19, 2021 Report Share Posted November 19, 2021 On 10/11/2021 at 17:56, IanD said: 48V isn't HV nowadays even allowing for maximum possible battery voltage, which is why all the mild hybrid cars use 48V. I think maybe the legislative voltage boundary was tweaked upwards by a few volts for exactly this reason... BTW here are some alternator plots which might be relevant -- shows why a Wakespeed controller which can pull back current at idle revs is a good idea... 😉 I don't think 48 V DC ever had been considered HV. Back in the early 70's I was working on 400 V DC batteries, which were broken into 50V sections to avoid any limitations on working on them. Link to comment Share on other sites More sharing options...
IanD Posted November 19, 2021 Report Share Posted November 19, 2021 (edited) 7 minutes ago, cuthound said: I don't think 48 V DC ever had been considered HV. Back in the early 70's I was working on 400 V DC batteries, which were broken into 50V sections to avoid any limitations on working on them. IIRC correctly the "HV" range is defined by the IEC (or EU, or whoever...) as starting at 60V, which is very close to the upper limit for 48V/52V nominal systems (LA or lithium) when maximum voltage during charging is considered. There was a post earlier saying that when they worked on 48V systems at Jaguar they did fall foul of the limit, so with the much more common use nowadays of 48V for mild hybrid cars it's possible that since then the limit has been moved up slightly to avoid them having to take all the extra (expensive) "HV" precautions, including training of mechanics and garages. Edited November 19, 2021 by IanD Link to comment Share on other sites More sharing options...
GUMPY Posted November 19, 2021 Report Share Posted November 19, 2021 Looking at the spec for my proposed new home solar system the battery (Solax T-BAT H 5.8) voltage is nominally 115vDC. Similarly the inverter (Solax X1-hybrid-3.7T) has a MPPT voltage range of 125-550vDC All well above the 60v "limit" I used to build 2500v 1/2amp power supplies as a hobby now they can be dangerous 😎 Link to comment Share on other sites More sharing options...
IanD Posted November 19, 2021 Report Share Posted November 19, 2021 (edited) 17 minutes ago, Loddon said: Looking at the spec for my proposed new home solar system the battery (Solax T-BAT H 5.8) voltage is nominally 115vDC. Similarly the inverter (Solax X1-hybrid-3.7T) has a MPPT voltage range of 125-550vDC All well above the 60v "limit" I used to build 2500v 1/2amp power supplies as a hobby now they can be dangerous 😎 The problem is that any commercial suppliers of systems above 48V nominal have to treat then as HV, which means a lot of extra regulations kick in including insulation, shielding of terminals, touchproof connectors, systems which turn off the power when you open up the case for maintenance and so on -- everything costs more, not just the hardware but people doing installation and maintenance need extra safety training and certification which isn't needed at 48V. None of which is impossible but it all costs money and often means specialist (less widely available, more expensive) components have to be used -- no more fuseholders or terminals that can be touched, no switches with exposed terminals and so on. Some suppliers (e.g. Victron) only do most of their gear up to 48V DC. If you (or the supplier) takes all these precautions then of course you can go up to much higher voltages, which is exactly what is done for higher power levels such as in EVs or *big* yachts, 400V DC is common here, or even 800V for the latest high-power fast-charging systems. No different to the precautions needed for 230Vac mains, but still ones that aren't needed at 48V. But at the power levels needed for canal boats -- even with electric drive, not just gas-free -- 48V is absolutely fine, and avoids all these problems. Which is why almost everybody uses it... Edited November 19, 2021 by IanD 1 Link to comment Share on other sites More sharing options...
peterboat Posted November 19, 2021 Report Share Posted November 19, 2021 1 hour ago, IanD said: IIRC correctly the "HV" range is defined by the IEC (or EU, or whoever...) as starting at 60V, which is very close to the upper limit for 48V/52V nominal systems (LA or lithium) when maximum voltage during charging is considered. There was a post earlier saying that when they worked on 48V systems at Jaguar they did fall foul of the limit, so with the much more common use nowadays of 48V for mild hybrid cars it's possible that since then the limit has been moved up slightly to avoid them having to take all the extra (expensive) "HV" precautions, including training of mechanics and garages. Both my Honda hybrids were over a 100 volts, one was a 2006 which was 160 volts from memory and the newer one might be just over the 100? I have noticed that the mild hybrids seem to be 48 volts nowadays but in truth I think that they are a waste of time and should be axed. For me a real hybrid should have a 70 mile range on electric Link to comment Share on other sites More sharing options...
peterboat Posted November 19, 2021 Report Share Posted November 19, 2021 26 minutes ago, IanD said: The problem is that any commercial suppliers of systems above 48V nominal have to treat then as HV, which means a lot of extra regulations kick in including insulation, shielding of terminals, touchproof connectors, systems which turn off the power when you open up the case for maintenance and so on -- everything costs more, not just the hardware but people doing installation and maintenance need extra safety training and certification which isn't needed at 48V. None of which is impossible but it all costs money and often means specialist (less widely available, more expensive) components have to be used -- no more fuseholders or terminals that can be touched, no switches with exposed terminals and so on. Some suppliers (e.g. Victron) only do most of their gear up to 48V DC. If you (or the supplier) takes all these precautions then of course you can go up to much higher voltages, which is exactly what is done for higher power levels such as in EVs or *big* yachts, 400V DC is common here, or even 800V for the latest high-power fast-charging systems. No different to the precautions needed for 230Vac mains, but still ones that aren't needed at 48V. But at the power levels needed for canal boats -- even with electric drive, not just gas-free -- 48V is absolutely fine, and avoids all these problems. Which is why almost everybody uses it... Completely agree, I run a 72 volt system because I needed that power for my system to work ok. The batteries then confirmed that choice as they are 36 volts so I have tried to be very careful covering every terminal also when the ignition is turned off so is the 72 volts Link to comment Share on other sites More sharing options...
IanD Posted November 19, 2021 Report Share Posted November 19, 2021 1 minute ago, peterboat said: Completely agree, I run a 72 volt system because I needed that power for my system to work ok. The batteries then confirmed that choice as they are 36 volts so I have tried to be very careful covering every terminal also when the ignition is turned off so is the 72 volts It's annoying but not too bad for you or any other DIYer, you'll only risk hurting yourself; it's much worse for anybody supplying systems on a commercial basis, who risks massive liabilities if they don't follow all the safety rules to the letter and somebody gets hurt. 8 minutes ago, peterboat said: Both my Honda hybrids were over a 100 volts, one was a 2006 which was 160 volts from memory and the newer one might be just over the 100? I have noticed that the mild hybrids seem to be 48 volts nowadays but in truth I think that they are a waste of time and should be axed. For me a real hybrid should have a 70 mile range on electric The mild hybrids are mostly an emissions-fiddling waste of time but they're cheap to add on to an existing ICE... 1 Link to comment Share on other sites More sharing options...
ditchcrawler Posted November 19, 2021 Report Share Posted November 19, 2021 1 hour ago, cuthound said: I don't think 48 V DC ever had been considered HV. Back in the early 70's I was working on 400 V DC batteries, which were broken into 50V sections to avoid any limitations on working on them. When I was at college I was told that it was because of telephones that the voltage level was set at 50 volts as if it had been any lower there would have been problems with the phone system and lots of it wouldn't have been allowed. As it was over 50 years ago I can't remember the details. Link to comment Share on other sites More sharing options...
IanD Posted November 19, 2021 Report Share Posted November 19, 2021 14 minutes ago, ditchcrawler said: When I was at college I was told that it was because of telephones that the voltage level was set at 50 volts as if it had been any lower there would have been problems with the phone system and lots of it wouldn't have been allowed. As it was over 50 years ago I can't remember the details. That's very likely the reason -- and since the telecoms "48V nominal" voltage came from big piles of flooded LA cells in the exchange battery room, the upper limit of this was also just about 60V, hence the choice of 60V as the LV-HV boundary... Link to comment Share on other sites More sharing options...
peterboat Posted November 19, 2021 Report Share Posted November 19, 2021 50 minutes ago, IanD said: That's very likely the reason -- and since the telecoms "48V nominal" voltage came from big piles of flooded LA cells in the exchange battery room, the upper limit of this was also just about 60V, hence the choice of 60V as the LV-HV boundary... On the continent they ran at higher voltage 75 from memory? Link to comment Share on other sites More sharing options...
cuthound Posted November 19, 2021 Report Share Posted November 19, 2021 1 hour ago, IanD said: That's very likely the reason -- and since the telecoms "48V nominal" voltage came from big piles of flooded LA cells in the exchange battery room, the upper limit of this was also just about 60V, hence the choice of 60V as the LV-HV boundary... 48 volts nominal, 24 cells, is a relatively recent (1980 onwards for the UK thing). Prior to that the main telecomms batteries were nominal 50 volt, 25 cells, floated at 51.5 volts and charged at up to 66 volts. 1 Link to comment Share on other sites More sharing options...
vmax666 Posted November 20, 2021 Report Share Posted November 20, 2021 (edited) One of the main reasons for using voltages below 60v is that this is considered a non lethal voltage. So less regulations have to be considered When using it although ac is slightly lower this is the reason 110v tools are used for on site power tools. The transformer is centre tapped giving 55v to earth so non leathal if you have a shock from the tool Edited November 20, 2021 by vmax666 Link to comment Share on other sites More sharing options...
Alan de Enfield Posted November 20, 2021 Report Share Posted November 20, 2021 53 minutes ago, vmax666 said: .....so non leather if you have a shock from the tool Just gives you a good 'leathering' .................. Which reminds me - not heard from Rusty 69 for a while now. 2 Link to comment Share on other sites More sharing options...
Tacet Posted November 20, 2021 Report Share Posted November 20, 2021 15 hours ago, cuthound said: 48 volts nominal, 24 cells, is a relatively recent (1980 onwards for the UK thing). Prior to that the main telecomms batteries were nominal 50 volt, 25 cells, floated at 51.5 volts and charged at up to 66 volts. Did not the voltage depend on how fast the subscriber spun the magneto? Link to comment Share on other sites More sharing options...
cuthound Posted November 20, 2021 Report Share Posted November 20, 2021 2 hours ago, Tacet said: Did not the voltage depend on how fast the subscriber spun the magneto? Even I'm not old enough to remember those! 🤣 Each main exchange battery was connected via a large circuit breaker, which had a high voltage trip to prevent you reconnecting a recently charged battery before the surface charge had dissipated, thus preventing you from getting away early. Don't ask me how I know this .. 🤣 Link to comment Share on other sites More sharing options...
Tacet Posted November 20, 2021 Report Share Posted November 20, 2021 3 hours ago, cuthound said: Even I'm not old enough to remember those! 🤣 Each main exchange battery was connected via a large circuit breaker, which had a high voltage trip to prevent you reconnecting a recently charged battery before the surface charge had dissipated, thus preventing you from getting away early. Don't ask me how I know this .. 🤣 I think you are old enough! Where two handsets were connected to a single line, you sometimes had a hand-wound magneto to generate a ring tone to call the other handset. Maybe they were no longer issued by the PO, but some were still around in the late 1970s. Link to comment Share on other sites More sharing options...
cuthound Posted November 20, 2021 Report Share Posted November 20, 2021 Just now, Tacet said: I think you are old enough! Where two handsets were connected to a single line, you sometimes had a hand-wound magneto to generate a ring tone to call the other handset. Maybe they were no longer issued by the PO, but some were still around in the late 1970s. Never came across that, but in the 70's I mainly worked in Central London. Link to comment Share on other sites More sharing options...
Peanut Posted November 21, 2021 Report Share Posted November 21, 2021 I just remember one in a phone box when I was very little, on the way to school, in about 1958/9, Acton, West London. Link to comment Share on other sites More sharing options...
TheBiscuits Posted November 21, 2021 Report Share Posted November 21, 2021 39 minutes ago, Peanut said: I just remember one in a phone box when I was very little, on the way to school, in about 1958/9, Acton, West London. Be very careful trying this nowadays. Most of the remaining phone boxes around here have defibrillators in them rather than telephones. Holding one to your ear and pushing the button would be a bad idea! 1 Link to comment Share on other sites More sharing options...
Alan de Enfield Posted November 21, 2021 Report Share Posted November 21, 2021 19 minutes ago, TheBiscuits said: Most of the remaining phone boxes around here have defibrillators in them rather than telephones. Holding one to your ear and pushing the button would be a bad shocking idea! Amended for you. 1 2 Link to comment Share on other sites More sharing options...
TheBiscuits Posted November 21, 2021 Report Share Posted November 21, 2021 18 minutes ago, Alan de Enfield said: Amended for you. A whole new twist on "I'll give you a buzz." Link to comment Share on other sites More sharing options...
Peter Laursen Posted August 22, 2022 Report Share Posted August 22, 2022 On 10/11/2021 at 17:04, nicknorman said: ...This was certainly the case with our Empirbus system - Steve didn’t particularly want to install it as he didn’t understand it, but was happy to do so to my design and my responsibility. Having Googled my day away in search of advice on Empirbus CLC I find myself as new member of the forum on Canalworld.net. I hope, you will bear with me, even though my boat has a mast and normally navigates Danish waters - and not canals... As far as I can tell, you have had the Empirbus CLC on your narrowboat for 10 + years? I just bought at boat (build 2009) with Empirebus CLC installed. One of the two membrane panels is failing. At a quoted price of EUR 1.000 (!) and no means of bypassing generally upon systems failure, as far as I can tell, I'm considering removing all of it and rewire the boat, if age is about to become a problem for the system. EUR 1000 would take me a fair bit 🙂. But I was wondering, what your experience with 10+ years of ownership is - and am I being to dramatic? Kind regards Peter 1 Link to comment Share on other sites More sharing options...
LadyG Posted August 22, 2022 Report Share Posted August 22, 2022 (edited) Welcome new member @Peter Laursen Peter, @nicknorman should be around soon, you will be able to use pm after about ten posts, so maybe you can think of a few other topics to boost your post count. There are a few rag and stick people here, some retired, some still active. PS try the search facility , top right box, in case there are other posts on this subject. Edited August 22, 2022 by LadyG 1 Link to comment Share on other sites More sharing options...
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