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#31
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24 VDC appliances?
(Larry W4CSC) wrote
My shop heater in winter is a 1KW Honda EU1000i power plant. I welded a pipe nipple on the little exhaust port . . . Hmm. The manual that came with my EU1000i went to great lengths in several languages to *don't do that*! I suppose if the length was short, not too restrictive, not near flammable materials, it could work. Its quiet enclosure . . . hidden away behind the cabinets. Hmm, The EU1000i wasn't designed to operate in an enclosure, might be hard on the plastic parts. Although big ventilation grates might make such an installation viable. Of course, restricting the exhaust with a long length of tubing and letting the generator recycle a good dose of it's own (hot) cooling air would just make it work harder and produce *more* heat g. |
#32
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24 VDC appliances?
The warning in the manual is for the carbon monoxide and to keep you
from suing them if you do what they tell you not to...... The enclosure has a big outlet where the heat comes out the end of the genset and two intakes, one in the bottom and one near the bottom on the end with the outlets. The plastic doesn't even get as warm as it would sitting in the sun being eaten alive by the UV rays from the sunshine. It runs 8 hours a day on the road all summer in a modified tool box bolted to the back door it just fits in. It's cooler in the cabinet than in the sun because of the volume of air the blower in it creates.... Operating in the van, in winter, the only end that gets warm is where the hot air comes out of it to heat my truck. I'd guess doing this recovers near 95% of the energy of the consumed fuel. Too bad boats don't use Deutz air-cooled diesels. You could dump the heat overboard in the summer around the dry stack and divert it into the cabin in winter to recover the waste heat with a thermostatically-controlled shutter to regulate its cabin temperature through a muffler to block the noise. I had Deutz V-16 engines driving 200KW gensets in Iran and they were fantastic engines, even running where the OAT was over 100F all day long! One injector clogged in 2 years and that was our fault some idiot put the filter in wrong. Change the oil every 150 hours and she'd just run and run 24/7/365 On 13 Jan 2004 21:51:56 -0800, (Mark) wrote: (Larry W4CSC) wrote My shop heater in winter is a 1KW Honda EU1000i power plant. I welded a pipe nipple on the little exhaust port . . . Hmm. The manual that came with my EU1000i went to great lengths in several languages to *don't do that*! I suppose if the length was short, not too restrictive, not near flammable materials, it could work. Its quiet enclosure . . . hidden away behind the cabinets. Hmm, The EU1000i wasn't designed to operate in an enclosure, might be hard on the plastic parts. Although big ventilation grates might make such an installation viable. Of course, restricting the exhaust with a long length of tubing and letting the generator recycle a good dose of it's own (hot) cooling air would just make it work harder and produce *more* heat g. |
#33
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24 VDC appliances?
"Larry W4CSC" wrote in message ... For those times, perhaps what is needed is a black plastic water heater you could haul up the mainmast to heat some medium for the night. What you would need is thermal mass. The key word here is "mass". It will take a lot of it, if you intend to pull heat out of it all night long. And it will be heavy. How much weight would you feel comfortable hauling up the mast? I know someone who has homemade panels hanging from the sunny side window sills to the ground below. This works great IF you have a sunny exposure BELOW the area where you use or store the energy. I have known people who live on a steep hill with a southern exposure (northern hemisphere, which means that the slope gets a lot of sun). It is somewhat common to construct a solar heater out of black ABS pipe that runs down the hill a ways. Heating swimming pools is common, but I know one person who had copper pipes embedded in the concrete slab of his home and ciculated the warm water to heat the slab. The key is that warm air/water will rise, so if the source of heat is lower you can create a natural flow of water. If the source of heat is above, then you will need to pump the water, and you may end up using more energy pumping than you would have heating. Rod |
#34
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24 VDC appliances?
Fatal Error.
The heating element is resistive. 120V 2KW element is approx 7 ohms. Reduce voltage to 24 v and current draw drops to 3.5 amps. Power is not a constant. "Larry W4CSC" wrote in message ... Wouldn't actually make much of a difference. If the 2KW water heater were running on 12V, it would draw 167A. On 24V it would still draw 83.3A, draining the batteries in a matter of minutes, not hours...... Then, comes the problem of battery real estate. in the same space it takes to put 500 amp-hours of 12V batteries, you get 250 amp-hours of 24V batteries.....the same exact kilowatt-hour rating. If you parallel two 130AH 12V deep cycles, you get 260AH at 12V. If you series them, you get 130AH at 24V......the same exact power output in KwH. You can use smaller wire, though....(c; Running large electrical loads of batteries is a pipe dream on these boats at any voltage. There just isn't room for a proper battery bank, like you'd need. A 350AH large golf cart battery, which is only 6 volts, is only 2.1Kwh but at a very low rate like 20A, not 200A. We run 4 of these monsters in 2 banks in series-parallel to get 12V at 700AH in Lionheart's engine room. You can't use all 700AH because that would really shorten their life, so you only discharge them about 400-500AH before charging, and that's stretching it. Then, it's so hard to get that last 15% to full charge, there's no point running the charging engine for hours more so you lose 15% more capacity charging them only up to 85% of full specific gravity. This battery bank of 4 is about 4' x 20" x 24" tall and 400 pounds of ballast. In comparison, each CELL of 126 cells in a WW2 submarine is about 7' high by 4' by 3' and puts out 2V at 6,250AH to drive the sub 48 hours at only 2 knots on TWO 126 cell banks...one forward, one aft. WW2 subs carried nearly 1000 TONS of batteries to accomplish this level of power. No wonder they sank a perfectly good boat! With an 80A alternator running flat out, you can recharge Lionhearts 400AH "standard discharge" in about 5.5 hours. Charging too fast, and this is almost too fast, makes charging more dangerous (heat) and boils off the electrolyte (hydrogen). With a tapering charge, it takes longer...6-7 hours. At 80A, the fanbelt better be TIGHT! Charging monster battery banks is another problem altogether..... Nothing is funnier than a boater with a new 4KW inverter carrying his electric heater down the dock with a big smile on his face....... The real answer is a super quiet insulated diesel genset with a small starting battery and a hundred gallons of #2 fuel oil.....an immense pool of liquid power...(c; The Navy prefers nuclear power but the refueling is messy. On Sat, 10 Jan 2004 22:20:53 GMT, misia wrote: On my new boat I will have a powerfull 24VDC battery bank charged by a diesel generator and auxiliary sources. I did a bit of search but couldn't find much- are there any 24 VDC appliances such as cooker/oven, fridge, AC and water heater you could recommend? I know I can run standard items through power inverter but I would prefer not to do it for the sake of reliability/efficiency/cost. I want to go totally electric (no gas) Regards Mi |
#35
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24 VDC appliances?
We use both 12 and 24 systems. They higher the required amperage the better
it is to use a higher voltage. We run winches, fridge, and autopilot hyd motor with 24 volt. All else is 12v. We use two 12 volt banks and one very large 24 volt bank. Charging is from both 12 and 24v HO alternators but are getting ready to add additional charging systems. Gas for cooking, diesel for heating. Hate to run a $20k motor to heat the cabin. Good luck, B "misia" wrote in message ail.from.there... On my new boat I will have a powerfull 24VDC battery bank charged by a diesel generator and auxiliary sources. I did a bit of search but couldn't find much- are there any 24 VDC appliances such as cooker/oven, fridge, AC and water heater you could recommend? I know I can run standard items through power inverter but I would prefer not to do it for the sake of reliability/efficiency/cost. I want to go totally electric (no gas) Regards Mi |
#36
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24 VDC appliances?
On Wed, 14 Jan 2004 12:36:42 -0800, "Rod McInnis"
wrote: "Larry W4CSC" wrote in message ... For those times, perhaps what is needed is a black plastic water heater you could haul up the mainmast to heat some medium for the night. What you would need is thermal mass. The key word here is "mass". It will take a lot of it, if you intend to pull heat out of it all night long. And it will be heavy. How much weight would you feel comfortable hauling up the mast? How about we transfer the heat into the thousands of pounds of lead in the KEEL? Is that mass enough??...(c; I was referring to a way we could heat the cabin in the DAYTIME, to reduce the cost of load of heating it, not eliminate it. If you pumped air from the cabin up into a black plastic bag, of sorts, exposed to the sun, the air coming back out into the cabin would be more than enough to heat the boat in the daytime....for free. I know someone who has homemade panels hanging from the sunny side window sills to the ground below. This works great IF you have a sunny exposure BELOW the area where you use or store the energy. I have known people who live on a steep hill with a southern exposure (northern hemisphere, which means that the slope gets a lot of sun). It is somewhat common to construct a solar heater out of black ABS pipe that runs down the hill a ways. Heating swimming pools is common, but I know one person who had copper pipes embedded in the concrete slab of his home and ciculated the warm water to heat the slab. Agreed, hence the FAN to overcome the problem, forcing air to circulate against its will into and out of the bag. The key is that warm air/water will rise, so if the source of heat is lower you can create a natural flow of water. If the source of heat is above, then you will need to pump the water, and you may end up using more energy pumping than you would have heating. Rod Pumping air into the thing is easy. 12V muffin fans draw almost no power and move a LOT of air. |
#37
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24 VDC appliances?
On Tue, 13 Jan 2004 00:58:42 GMT, Rick
wrote: While I have not bothered to search, the selection of marine equipment available in 24VDC must be very very small. Most all little boats use 12VDC, most larger boats use 110/220/480VAC. Many mid-size yachts (45-80 ft ) have dual 12/24 V systems. 12 V for electronics that are low-power and often don't come in 24V versions, 24V for Bow/sternthrusters, windlasses, electrical winches etc. Mainly too keep the cables reasonable. /Marcus -- Marcus AAkesson Gothenburg Callsigns: SM6XFN & SB4779 Sweden Keep the world clean - no HTML in news or mail ! |
#38
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24 VDC appliances?
I knew what Larry intended: why didn't you?
Brian W On Wed, 14 Jan 2004 20:59:50 GMT, "Morex Support" wrote: Fatal Error. The heating element is resistive. 120V 2KW element is approx 7 ohms. Reduce voltage to 24 v and current draw drops to 3.5 amps. Power is not a constant. "Larry W4CSC" wrote in message ... Wouldn't actually make much of a difference. If the 2KW water heater were running on 12V, it would draw 167A. On 24V it would still draw 83.3A, draining the batteries in a matter of minutes, not hours...... |
#39
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24 VDC appliances?
If y'all would just hang on for the next design generation of auto
electronics, you might could use the 42 volt electrics..... Brian Whatcott Altus OK On Wed, 14 Jan 2004 17:12:08 -0500, "Bryan B" wrote: We use both 12 and 24 systems. They higher the required amperage the better it is to use a higher voltage. We run winches, fridge, and autopilot hyd motor with 24 volt. All else is 12v. We use two 12 volt banks and one very large 24 volt bank. Charging is from both 12 and 24v HO alternators but are getting ready to add additional charging systems. Gas for cooking, diesel for heating. Hate to run a $20k motor to heat the cabin. Good luck, B "misia" wrote in message mail.from.there... On my new boat I will have a powerfull 24VDC battery bank charged by a diesel generator and auxiliary sources. I did a bit of search but couldn't find much- are there any 24 VDC appliances such as cooker/oven, fridge, AC and water heater you could recommend? I know I can run standard items through power inverter but I would prefer not to do it for the sake of reliability/efficiency/cost. I want to go totally electric (no gas) Regards Mi |
#40
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24 VDC appliances?
Larry,
That keel idea is a great one. He could collect solar heat with the mast and pump it to the keel for storage. And of course this would make Scotty very happy cause the keel would have to be covered with foam for insulation. Regards, Ron I don't recieve e-mail at this address because of spam. E-mail me at crtsrATmsnDOTcom. |
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