Running generator at night.
- Thread starter Dan50
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danemayer
Well-known member
Onan Spec Sheet attached. Page 2 shows average fuel consumption. A 40# propane tank has about 9 gallons of fuel. 30# is about 7 gallons. Pretty easy to use most of a tank overnight with a/c running.
scottyb
Well-known member
I ran my gas Onan 72 hours and 84 hours straight on two separate occasions, only shutting down to check oil and add fuel every 12 hours. I ran 1 AC most of the time except for a couple hours each evening for a rapid cool down after 105 degree days. It averaged 0.5 gph on both occasions. This type of use might be problematic on propane unless you carry extra bottles. I think Onan's specs show the consumption rate a little higher on propane.
Jim.Allison
Well-known member
To run a furnace and a CPAP is going to be about 8/10 of a gallon per hour. the furnace is intermittent usage and the other is very little wattage. Those two items amount to nothing as far as load is concerned. So use the fuel burn rating at 8/10 per hour.
Geodude
Well-known member
Dan, I would be pretty nervous about running a genny at night but that's just me. ;-) There's a CPAP in our lives now, and for dry camping I plan to run three group 27 deep cycle batteries -- the trailer came with two and I have a spare that I will tie in as needed. To run the CPAP I bought a 12V adapter here in Ottawa for $30 or $40. I just need to buy the female socket and wire it in to a 12V source in the bedroom. From what I've read it should run the machine for two or three nights on the battery. Less of course with the furnace running at one of those winter trips south. But I figure I'd recharge while driving the next day or run the genny to top up the batteries.
If you want the details on the 12V we bought, it's for a System One 60 series machine.
If you want the details on the 12V we bought, it's for a System One 60 series machine.
Jim.Allison
Well-known member
All you have to do is search you CPAP machine manufacturer and model number, you can find all the accessories for that machine. I had no problem getting my DC cord.
The switchplate with the female DC port (cigarette lighter port) was eventually located at an RV parts dealer. I had little success finding anything but a surface mount on the net, but if you want a regular looking switchplate type check the RV parts stores.
The switchplate with the female DC port (cigarette lighter port) was eventually located at an RV parts dealer. I had little success finding anything but a surface mount on the net, but if you want a regular looking switchplate type check the RV parts stores.
Depending on the brand of CPAP, you should be able to make a 12Volt DC cig adapter for it. I have had two different CPAP machines and both use AC on the primary and 12 Volt DC on the secondary (The part that goes into the machine). I made a cord for mine and it runs all night. This is more efficient than using an inverter to get AC that is just being stepped back down to 12V DC. That will likely solve your CPAP issues. You'll probably still want a genset for recharging in the morning. I also know, when cold enough, my furnace would suck the batteries dead in my old RV (it was 12 years old and still had the original pair of 12 volt batteries). I have never ran the gen when sleeping which is just a personal choice, just not comfortable doing so. Plus it is very noisy even though it is in a box next to the landing gear (Onan 4K gas). I was actually looking through previous posts about quieting the noise when I saw this post.
Jim.Allison
Well-known member
For $25 bucks I would not make one, if you look at the factory DC cord, you will see a module molded into the cable on each end.
Edited: the modules turn out to be EMI filters, which would be a good thing to have.
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Concur $25 is reasonable if this is not within your skillset, however, in my case, it was a straight 12 volts, no in-line filters from the output of the secondary, just a connector I had trouble finding the right size for. (I actually used the original cord, added a switch and a cig connector. I just use the switch to select the AC input or the DC input. Works fine, last a long time 
Jim.Allison
Well-known member
No kidding are you telling me that amps, volts, and watts are all different?
Good job on the EMI Save. now that I know, I could have made my own, with parts from Radio Shack.
Good job on the EMI Save. now that I know, I could have made my own, with parts from Radio Shack.
avvidclif
Well-known member
To put it in easier terms to understand we'll use water as electricity.
Voltage is the pressure
Amps is the volume
Watts is how much water is moving past a point
1V @ 300A won't hurt you. Lots of water but very little pressure, a gentle flood.
3000V @ .1A (one tenth) will slice and dice you like a knife.
Both have the same Watts; (Ohms Law, Watts = Volts x Amps), 1V x 30A0 = 300W, 3000V x .1A = 300W Same amount of water but the potential for human damage is much greater when the pressure goes up.
Make sense?
Bohemian
Well-known member
If you are going to make a metaphorical analogy, you should at least get it right.
Jim.Allison
Well-known member
.1 to .2 amps will kill you. Fortunately the resistance of the human body prevents that much current from being delivered through the brain and heart. However the the presents of sweat and moisture lowers the resistance of the human body. I was changing a fuel filter on my RAM the other day. My sweaty arm was touching the positive terminal and I felt a tingle from only 12 to 14v.
Through ohm's law, it is impossible to have a volt without an amp and vice versa. Since we are talking a milliamp it is a rare circuit that cannot kill you. It is said that people have been killed by 42v and .1 amps. the upshot is that one should be extremely careful when working with electricity DC or AC. In low voltage systems like a 12v or 24v house battery, there is little or no concern of electrocution, but a tool that creates a direct short can turn white hot and cause an explosion, fire or severe burns. So one way or the other, electricity can get you, and get you bad. And we all take it for granted. I am surprised that more people are not electrocuted. A friend of mine was surprised when he tried to jump his car battery. The post was broken internally and the battery exploded. He was not severely injured, but his clothing was ruined and his skin was burned by sulfuric acid. I got copper sulfate in my eye while cleaning a battery post. The corroded wire flicked it into my eye. I spent over a month healing from that. I was prescribed saline bags which I had to use religiously for 3 days to heal the burns to my eye.
From all that was presented, all I learned is that the two mouldings on the factory cable are simple EMI components available from any internet electronics supplier. So a homemade cable is completely possible for a person who has the desire to build one. In fact, I probably have enough cable ends and EMIs in my abandoned computer cable drawer to assemble one without purchasing anything.
I made a mistake on the current thing and the design of the OEM cable. Now that we have the facts on the issue, I'm done with it.
Through ohm's law, it is impossible to have a volt without an amp and vice versa. Since we are talking a milliamp it is a rare circuit that cannot kill you. It is said that people have been killed by 42v and .1 amps. the upshot is that one should be extremely careful when working with electricity DC or AC. In low voltage systems like a 12v or 24v house battery, there is little or no concern of electrocution, but a tool that creates a direct short can turn white hot and cause an explosion, fire or severe burns. So one way or the other, electricity can get you, and get you bad. And we all take it for granted. I am surprised that more people are not electrocuted. A friend of mine was surprised when he tried to jump his car battery. The post was broken internally and the battery exploded. He was not severely injured, but his clothing was ruined and his skin was burned by sulfuric acid. I got copper sulfate in my eye while cleaning a battery post. The corroded wire flicked it into my eye. I spent over a month healing from that. I was prescribed saline bags which I had to use religiously for 3 days to heal the burns to my eye.
From all that was presented, all I learned is that the two mouldings on the factory cable are simple EMI components available from any internet electronics supplier. So a homemade cable is completely possible for a person who has the desire to build one. In fact, I probably have enough cable ends and EMIs in my abandoned computer cable drawer to assemble one without purchasing anything.
I made a mistake on the current thing and the design of the OEM cable. Now that we have the facts on the issue, I'm done with it.
Oct 21, 2013 - A NASCAR fan was found dead in an RV at a campground near Alabama's ... The Tennessee man and his wife were reportedly camping out ahead ...for heat and that there was a problem with the generator's exhaust system.
I remember when this happened, for we heard about it boondocking at Martinsville race track. Going back in Oct, and concerned, for it can get really cold.
I remember when this happened, for we heard about it boondocking at Martinsville race track. Going back in Oct, and concerned, for it can get really cold.
szewczyk_john
Well-known member
I'm planning on being there too. We stay at the Jim Mills automotive dealer lot. You pay a little extra put you get a flat spot and Don't have to worry about mud or the wet clay. He has some spots that he run electric to but I do not know how much that costs. Easy walk to the track. Test your carbon monoxide detector and understand that not all the facts are disclosed in terrible stories like you posted. About 13 years ago, a guy showed up in a beat up older trailer when I used to stay behind the water tower by the railroad tracks for the Martinsville race. He came to my trailer asking to borrow allen wrenches as he didn't have any. He informed me that he had a gas leak and furnace trouble. I offered my help and my little buddy LP heater that we carry as a backup. he declined. returned my tools to me and informed me that he had it all fixed up. 2 nights later he had a small explosion and fire destroyed that old trailer rather quickly. turns out that he didn't fix anything and was using the fires on the cooktop for heat in a trailer with a gas leak. The only thing reported in the newspaper the next day was that an accident happened resulting in a fire. The trailer was totally gone before the fire department even got called.
Bohemian
Well-known member
A safer possibility is to heat with a heat pump(s) off an inverter(s) and a big bank of batteries.
There is about a 10-1 to 15-1 advantage. Burning LP is achieve by converting energy (LP gas) into heat (another form of energy) . 1 joule of fuel provides 1 joule of heat. Electric resistance heating is the same 1 joule out of the batteries yields 1 joule of heat into the RV. A heat pump uses it's input energy to MOVE heat from the outside to the inside of the RV. (The reverse of an AC). 10-15 joules of heat are MOVED into the RV for every joule of fuel consumed.
If you have a big bank of batteries and an appropriate inverter, you would not need to run the gen overnight.
The problem with heat pumps is that they don't work well below about 40F and no heat is pumped into the basement on models where the furnace pumps heat into the basement. So deep winter is a bigger problem as always.
There is about a 10-1 to 15-1 advantage. Burning LP is achieve by converting energy (LP gas) into heat (another form of energy) . 1 joule of fuel provides 1 joule of heat. Electric resistance heating is the same 1 joule out of the batteries yields 1 joule of heat into the RV. A heat pump uses it's input energy to MOVE heat from the outside to the inside of the RV. (The reverse of an AC). 10-15 joules of heat are MOVED into the RV for every joule of fuel consumed.
If you have a big bank of batteries and an appropriate inverter, you would not need to run the gen overnight.
The problem with heat pumps is that they don't work well below about 40F and no heat is pumped into the basement on models where the furnace pumps heat into the basement. So deep winter is a bigger problem as always.
I have the same problem of wanting to overnight in places where no electricity is available. My solution was as follows:
First, I had an Onan 6.5KW propane generator installed. I replaced my 30 pound tanks with 40's, then built a rack in my gagage area for the two 30's. I put Stay Longer kits on both sides, allowing me to tie in the 30's (chained in place outside the RV) to the propane system. (as an OBTW, this also allows me to use my onboard propane to power my outside grill). As soon as I got the generator, I also got a Genturi. I have used the generator twice now, with no problem with exhaust, nor do I think it would ever be a problem as long as proper maintenance and integrity checks are done on the generator and exhaust system.
however, I also know that we will be going places that will have "quiet hours" and I need to have a way to provide power to both my DW's and my CPAP's. I am installing an Automatic Bus Transfer switch (ABT) with a feed from the breaker on the AC Distribution panel, a second feed from an Inverter which will be fed DC from the feed at the entrance to the DC Distribution panel with a remote on/off switch on the control panel and the output hooked to the feed to the bedroom outlets. This way, I have power to my bedroom AC outlets from the main panel during normal conditions, either shore power or generator, and from the inverter during quiet hours. In the event of burning down the batteries below the ability to start the generator, back the truck up, hook up the external power supply, fire up the truck, fire up the generator, unplug the truck, then let the converter recharge the battery.
First, I had an Onan 6.5KW propane generator installed. I replaced my 30 pound tanks with 40's, then built a rack in my gagage area for the two 30's. I put Stay Longer kits on both sides, allowing me to tie in the 30's (chained in place outside the RV) to the propane system. (as an OBTW, this also allows me to use my onboard propane to power my outside grill). As soon as I got the generator, I also got a Genturi. I have used the generator twice now, with no problem with exhaust, nor do I think it would ever be a problem as long as proper maintenance and integrity checks are done on the generator and exhaust system.
however, I also know that we will be going places that will have "quiet hours" and I need to have a way to provide power to both my DW's and my CPAP's. I am installing an Automatic Bus Transfer switch (ABT) with a feed from the breaker on the AC Distribution panel, a second feed from an Inverter which will be fed DC from the feed at the entrance to the DC Distribution panel with a remote on/off switch on the control panel and the output hooked to the feed to the bedroom outlets. This way, I have power to my bedroom AC outlets from the main panel during normal conditions, either shore power or generator, and from the inverter during quiet hours. In the event of burning down the batteries below the ability to start the generator, back the truck up, hook up the external power supply, fire up the truck, fire up the generator, unplug the truck, then let the converter recharge the battery.
