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#31
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Check a lease on an apartment, or the condo codes, storing propane on or in your
residence or even on your deck is a violation. You wrote: In article , "Dave" wrote: i bet you also find that storing explosive gasses in an apartment are also against code. and laywers would probably consider a fuel cell a generator also. Well not really, as a lot of apartments have Explosive GAS piped right into them..... Never heard of Natural Gas, or even Propane, I guess.... Both are Extremely Explosive, when mixed with air in the correct ratio.... Duh..... |
#32
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On Fri, 27 Oct 2006 01:59:24 GMT, ml wrote:
it usually starts simple, i wanted somthing better than battery power Hi Myles, You are suffering from easy access to an answer to the wrong question. First, investigate/research DC-DC converters. We've been through this once before, haven't we? The various storage methods you've been cycling through Cell/Battery/Cap all have different voltage parameters compared to the eventual load. True, the battery naturally fits that 13.6V requirement, but it eventually fades. With the right DC-DC converter, you can accommodate almost any scenario you've described and efficiently transform to a steady reliable voltage source capable of meeting the current load. With the right DC-DC converter, you can also meet the requirements for recharging a cap or a battery from any other source (Cell/Battery/Cap). Flexibility allows you to move from any power source to another and still supply your load reliably. 73's Richard Clark, KB7QHC |
#33
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![]() ml wrote: In article , Tom Ring wrote: ml wrote: omitted) it's quite meets code, very small, very light dosn't pollute or stink seemed rather sexy the jado can also be powered from small cartridges making the unit selfcontained and very portable, however this isn't a requirement of mine but cool benni the only con for me, seems to be a)not totally going to give me 100w at full load b) i wish the unit was more than a puny 100w the larger units i would have to pay full list for and are therefore outta reach so solath and experiment Ok, I have applied a simple power budget to what you stated your original desire was, as opposed to your cut down 2m 5W system. Using a rig I own, an FT-897, on HF. Assume 90% receive at 1 amp. Assume 10% transmit at 15 amps with 100 watts output, (measured as opposed to the 22 amps claimed in the docs) This gives 2.4 amps average consumption. (Check my math, the doctor did a lot during my pre-op today) 1 week is 168 hours which gives us 403 ampere hours. 100AH deep cycle batteries are around 100 each (or less), So that's about $400 for all the batteries you need for a week without sleep. A modern top of the line charger, such as produced by Schumacher, is less than $100, does automatic desulfation, will charge at 50 amps or greater, and weighs about 6 pounds. So now we are at under 500 dollars for an emergency power for any ham that needs to run an HF rig for a whole week. I just don't see why you want to use the fuel cell, it makes no sense. tom K0TAR tom, am i to understand you had some surgery today? if so, i hope all is well with you and taking the time to write is appreciated i am guessing roy's calculation of the total ampre hrs needed is closer to being correct, but it's 5am and i kinda don't know how to calculate that so i dunno as stated in my earlier post i don't have the formulas so i can't act to confirm but i nod my head and presume it's all correct based on roys math you are correct about what the rig is doing mine is exactly simular i would calculate based on 20amps re your last comments on why i would want a fuel cell, it should be very clear in all my many posts 5480 watt-hours of battery is more $$ and large than i have practical room for i can get the fuel cell for practically nothing and i just thought it might be able to offer some useful power to top off a battery to provide some b/u power why not? and also be a fun experiment it runs quiet , clean and i can get all the fuel i want free always, i would never be able to get fossel fuels in a blackout or other emerg so now i inch a drop closer knowing how many what hours my original abandoned goal would draw , however my current stated goal is to just power my 5w tx output(draws4amps) 2m mobile rig and try to calculate how much the battery would be drained in a 1min tx and then see if the 12v 7amps comming out of the jado would recharge it fast enough i believe that is what must be calculated for just not sure how do it, unless you still say a 7amp battery is still 'ok' my goal was to be able to calculate so a 7amp battery(or what ever is needed optically this seems like a too low a #)) w/a 1min 4amp load would be ??%drained then based on manuf spec's for the battery we could calculate how much power &time would be needed to top it back off then it would be simple enough to see if the output of the jado is sufficient i think thats all thats needed i think that's simple but i dunno how to calculate it thanks all i really wanted to do If your rig draws 4 amps (I assume that's on transmit; it would be an awful lot of power for a modern receiver), and the fuel cell can put out 7 amps continuously albeit at slightly reduced voltage, and I assume it can put out 4 amps at less of a reduction, why are you worried about it? Unless you are VERY long-winded with your transmissions, a small 7amp-hour sealed lead acid battery would give you a couple hours operating time even if it wasn't being continuously recharged. I'd actually opt instead for some voltage stabilization at the fuel cell output: a buck-boost regulator would do it. If you trust the fuel cell to do its job, then trust it. If you don't, then provide a backup. So what I read between the lines you've written is that you're going to get this fuel cell, but you don't really trust it. You don't even trust it to come close to what are apparently its published ratings. Pretty much all the formulas you need to figure all this stuff out: power = voltage times current (watts = volts * amps) energy = power times time (joules = watts * seconds) -- total energy needed = sum of (each current times the length of time that current is drawn) amp-hours = amps * hours = amps * seconds / 3600sec/hr battery energy storage in watt-hours = amp-hour rating * volts (assuming full charge) battery energy storage in joules = amp-hour rating * volts * 3600 sec/hour capacitor energy storage = (initial charge voltage)^2 * capacitance / 2 joules = watt-seconds = volts^2 * farads / 2 watt-hours = joules/3600 = volts^2 * farads / 7200 Where is it that you can get a license without knowing at least this much? Why so much trouble with the concepts of power and energy calculated from current, voltage and time? (Why is this posted to an antennas newsgroup?) Cheers, Tom |
#34
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![]() ml wrote: In article , Tom Ring wrote: ml wrote: omitted) it's quite meets code, very small, very light dosn't pollute or stink seemed rather sexy the jado can also be powered from small cartridges making the unit selfcontained and very portable, however this isn't a requirement of mine but cool benni the only con for me, seems to be a)not totally going to give me 100w at full load b) i wish the unit was more than a puny 100w the larger units i would have to pay full list for and are therefore outta reach so solath and experiment Ok, I have applied a simple power budget to what you stated your original desire was, as opposed to your cut down 2m 5W system. Using a rig I own, an FT-897, on HF. Assume 90% receive at 1 amp. Assume 10% transmit at 15 amps with 100 watts output, (measured as opposed to the 22 amps claimed in the docs) This gives 2.4 amps average consumption. (Check my math, the doctor did a lot during my pre-op today) 1 week is 168 hours which gives us 403 ampere hours. 100AH deep cycle batteries are around 100 each (or less), So that's about $400 for all the batteries you need for a week without sleep. A modern top of the line charger, such as produced by Schumacher, is less than $100, does automatic desulfation, will charge at 50 amps or greater, and weighs about 6 pounds. So now we are at under 500 dollars for an emergency power for any ham that needs to run an HF rig for a whole week. I just don't see why you want to use the fuel cell, it makes no sense. tom K0TAR tom, am i to understand you had some surgery today? if so, i hope all is well with you and taking the time to write is appreciated i am guessing roy's calculation of the total ampre hrs needed is closer to being correct, but it's 5am and i kinda don't know how to calculate that so i dunno as stated in my earlier post i don't have the formulas so i can't act to confirm but i nod my head and presume it's all correct based on roys math you are correct about what the rig is doing mine is exactly simular i would calculate based on 20amps re your last comments on why i would want a fuel cell, it should be very clear in all my many posts 5480 watt-hours of battery is more $$ and large than i have practical room for i can get the fuel cell for practically nothing and i just thought it might be able to offer some useful power to top off a battery to provide some b/u power why not? and also be a fun experiment it runs quiet , clean and i can get all the fuel i want free always, i would never be able to get fossel fuels in a blackout or other emerg so now i inch a drop closer knowing how many what hours my original abandoned goal would draw , however my current stated goal is to just power my 5w tx output(draws4amps) 2m mobile rig and try to calculate how much the battery would be drained in a 1min tx and then see if the 12v 7amps comming out of the jado would recharge it fast enough i believe that is what must be calculated for just not sure how do it, unless you still say a 7amp battery is still 'ok' my goal was to be able to calculate so a 7amp battery(or what ever is needed optically this seems like a too low a #)) w/a 1min 4amp load would be ??%drained then based on manuf spec's for the battery we could calculate how much power &time would be needed to top it back off then it would be simple enough to see if the output of the jado is sufficient i think thats all thats needed i think that's simple but i dunno how to calculate it thanks all i really wanted to do If your rig draws 4 amps (I assume that's on transmit; it would be an awful lot of power for a modern receiver), and the fuel cell can put out 7 amps continuously albeit at slightly reduced voltage, and I assume it can put out 4 amps at less of a reduction, why are you worried about it? Unless you are VERY long-winded with your transmissions, a small 7amp-hour sealed lead acid battery would give you a couple hours operating time even if it wasn't being continuously recharged. I'd actually opt instead for some voltage stabilization at the fuel cell output: a buck-boost regulator would do it. If you trust the fuel cell to do its job, then trust it. If you don't, then provide a backup. So what I read between the lines you've written is that you're going to get this fuel cell, but you don't really trust it. You don't even trust it to come close to what are apparently its published ratings. Pretty much all the formulas you need to figure all this stuff out: power = voltage times current (watts = volts * amps) energy = power times time (joules = watts * seconds) -- total energy needed = sum of (each current times the length of time that current is drawn) amp-hours = amps * hours = amps * seconds / 3600sec/hr battery energy storage in watt-hours = amp-hour rating * volts (assuming full charge) battery energy storage in joules = amp-hour rating * volts * 3600 sec/hour capacitor energy storage = (initial charge voltage)^2 * capacitance / 2 joules = watt-seconds = volts^2 * farads / 2 watt-hours = joules/3600 = volts^2 * farads / 7200 Where is it that you can get a license without knowing at least this much? Why so much trouble with the concepts of power and energy calculated from current, voltage and time? (Why is this posted to an antennas newsgroup?) Cheers, Tom |
#35
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K7ITM wrote:
-- total energy needed = sum of (each current times the length of time that current is drawn) You probably meant to say current times time is total charge. 73 de AC6XG |
#36
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Roy Lewallen wrote in
: Tom Ring wrote: . . . 1 week is 168 hours which gives us 403 ampere hours. . . . which at 13.6 volts is about 5480 watt-hours. This is the energy storage requirement. The OP asked about using a capacitor. The energy stored in a capacitor is C * V^2 / 2. For capacitance in farads and voltage in volts, the result is joules, or watt-seconds -- you need 5480 * 3600 ~ 20,000,000 joules in round numbers. So suppose you wanted to store this same amount of energy in a capacitor, and you had a switching regulator which would handle 50 volts maximum input voltage. Solving for C, assuming it's charged to 50 volts, C = 20,000,000 * 2 / (50^2) = 16,000 farads. This assumes you can get all the energy out of the capacitor, which requires your regulator to work down to zero volts. But you'll get 3/4 of the energy out of it if your regulator cuts off at 25 volts, 7/8 if it cuts off at 12.5 volts, etc. How does that sound? Roy Lewallen, W7EL Send that to me in CW and I'll have a look at it. SC |
#37
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![]() Jim Kelley wrote: K7ITM wrote: -- total energy needed = sum of (each current times the length of time that current is drawn) You probably meant to say current times time is total charge. 73 de AC6XG Yeah, probably something like that. ;-) Actually, what I meant to write was more like: -- total energy needed = voltage * sum of (each current times the length of time that current is drawn. Lesseee...unit analysis...volts * amps * time. OK, that looks better. Thanks, Jim. Cheers, Tom |
#38
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You wrote:
Well not really, as a lot of apartments have Explosive GAS piped right into them..... Never heard of Natural Gas, or even Propane, I guess.... Both are Extremely Explosive, when mixed with air in the correct ratio.... Duh..... You will find that from a legal perspective that natural gas piped in is not at all the same as storing a tank of hydrogen. Natural gas and propane are very highly regulated as to installation, equipment attached, etc. Very different than your tank of H2 will be. tom K0TAR |
#39
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On Thu, 26 Oct 2006 08:53:31 -0700, Jim Kelley
wrote: Fuel Cell??? That is a pretty pricey option. More than likely it is 100WH (Watt-hour, not Watt) rated. https://jadoopower.com/fuel_cell.html Very interesting. But Seems like those fuel canisters are just a bit on the pricey side. And what fuel do they indeed use? Complete lack of info on that. I see the website mentions refill stations. What kind of power do those use? How do they work. Tony |
#40
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On Sat, 28 Oct 2006 16:01:03 GMT, Tony VE6MVP
wrote: Seems like those fuel canisters are just a bit on the pricey side. When I run the numbers through I get N-Gen at $1000 and Honda EU1000i at $790. Close enough for now. But the fuel is much different. - N-Stor130 is 130 W-h for a cost of $450. But the Honda fuel consumption is 3.8 hours at rated continuous duty of 900 watts. Or a 0.6 US gal tank of gas produces 3420 W-h. That's about $2. So 130 W-h for $450 or 3420 W-h for $2. Unless you really, really need that absolute quiet of the fuel cell or have unusual conditions such as the space shuttle then it's a no brainer to me. Tony |
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