Posted: 12/12/2007 6:11:13 AM EDT
|
I've been evaluating my preparedness for this winter and I have one teeny little problem. Electrical delivery is extremely reliable in my area. Our house is only a couple of blocks from a sub-station and we can expect any power outage from weather conditions to be resolved in twenty four hours or so. That has been my previous experience and it's reasonable to expect that in all but the direst of extremes. I'm looking at power inverters that I can install on either the Jeep or the Cub Cadet that can provide AC to power my boiler's circulator pump and damper until power is restored. Since the Jeep is the BOV, I figure this can serve multiple purposes. The boiler runs on a 15 amp circuit and probably pulls about half that at startup. I haven't put a meter on it to know for sure. I'm ready to pull the trigger on a generator but this really seems like overkill. I figure the Jeep will idle for extended periods on a tank of gas. It's fuel injected and water cooled so idling really isn't that big of a deal. What are the down sides to a 1500w inverter? What's everyone's experience? Is it a dumb idea? I'm full of dumb ideas, it would seem. J. |
|
I had a lower wattage inverter that I once hooked to the car (as per instructions). It worked fine. The deal with the genny is the convenience of having a 20amp plug interface to the transfer switch/breaker box and avoiding all the attendant wires all over the place. (even though its hooked up to the house you don't have to turn everything on  )But if that's all you'll need it for it should be ok. Make sure the alternator can keep up. eta: Another consideration is rain. How will you be setup, inverter-wise, if it is raining? Running the vehicle in the garage, even with the door open, .............. Humidity can have an effect as well. |
|
I've got a 1500W Inverter, it's huge (compared to my 400W inverters), but it works. However it won't run from your vehicle for very long. A 1500W inverter running at full capacity requires a minium of 137.5 amps from your vehicles 12v system. That's for 1500W plus the 10% 'loss' most of thse seem to have. I don't know of many standard vehicles with 140amp alternators (you'll need a bit bigger as you'll still need power to run the engine). If you draw more than the Alternator can deliver you'll start pulling power from the battery (and draining it). What I suggest is you get a Kill-O-Watt meter (yes that's a brand name) and see if you can get it wired into your system so you can determine the amount of power the pump really needs. If it only needs the 1500W at startup, but can run at 700 watts then your Jeep might be able to handle that power load w/o draining the battery. IMHO 1500w inverters from vehicles are best used for things like running a fridge/freezer for short periods to cool them down or for running power tools in short bursts. Oh and don't forget an inverter tha big needs to be wired to the battery - not through the cigarette lighter
|
The Jeep has the high capacity alternator, I ordered it that way. There's lots of room under the hood. I'm only running a single battery but there's room for a second and an inverter. Dual batteries would pretty much be a given for this application. I've considered a welder setup but that would be more money than I'm willing to spend right now. By the time I get a dual battery setup, a decent inverter, and all the odds and ends I can see this costing as much as a generator. I'm just trying to look at it from a practicality point of view. The appeal to me is to have backup power and have it packed neatly into the BOV. My boiler has a quarter horsepower pump that runs only when the system is calling for heat. Typically, it will call for heat for maybe a half hour or so and then sit idle for maybe forty five minutes to an hour. The call for heat is higher as temperatures drop of course. How long is an inverter willing to run before it starts overheating? |
IIRC that means it has a 110-120 amp alternator instead of the 90 amp one (at least with the 4.0). I have seen aftermarket 187amp alternators - if you got something like this then I think you may do ok.
Check to ensure any inverter you want to mount there is water/weather proof. I know mine isn't . So it only get's hooked up when needed and never when the vehicle may be moved.
Depends on the airflow, ambient air temperture, and load. If done properly you shouldn't have an overheating issue. But under a jeeps hood with a running engine at near full capacity - you may have an issue. |
Answers all my questions. It looks like a no go for the inverter. Maybe if I was doing a welding setup but that's not happening right now. Thanks! J. |
| All the inverters I have have fans and cooling openings. Mounted under the hood I'd be real concerned with filling the inverter with crud. Once the internal heat sinks get covered the inverter won't be able to output anything like full capacity before it shuts down due to overheating. |
Yep - you might be able to get away with it mounted under the seat or in the back - providing you have a place where dirt won't get into it. It will also require some HEAVY duty cabling to hook it up to the battery. |
| op why not just get 2 6v golf cart batts and mount them on a cart or in a rubbermaid container with a trickle charger mounted with them and an inverter mounted on the top? the trickle charger will keep the batts charged and since your never out of power for more than 24 hours, should be more than enough to run that. if you put it on a cart you could then role it inside the house and power lights or tv. |
I have been thinking about something just like that using a heavy duty hand truck with some fabricated brackets/shelves...a pair of 6V golf cart batteries, a battery charger, a 1000w + inverter and a Honda/Yamaha 2000w generator and maybe even a charge controller with a 100W solar panel. Most panels are similar height/width to the big hand trucks and it should be possible to build a vertical storage slot for 1 panel and with the right cabling you could 'deploy' it from the truck to somewhere close by) Its just a project in my mind right now but I think I could make an all-in-one power center based on the hand truck and it would be reasonably portable. A couple of ratchet straps and you could secure it to a porch railing, tree, outside pipe; etc. Not ideal for everybody but as an apartment dweller I have been trying to figure out a way of making a generator/battery setup thats semi-luggable. Would be best suited for the heavy duty extension cord type of use but thats what my reality is with my current housing (apartment) |
A golf cart battery has roughly 220 amp/hours. Say you're lucky and can draw it down to 25%. That is 165 amp/hours. Assume the motor only runs at 700W - add 10% for loss. That's just over 2.5 hours of run time for the motor in the OP's scenario till the batteries are drained. For light duty (say run some lights or a small TV) - even a freezer periodically it would work. |
|
I checked out my pump. It's marked as .75 amps. The power damper doesn't have a tag but it's just a little servo motor that either swings the damper open or closed. It's beginning to look to me as if for a boiler setup like mine, an inverter might be one way to get backup power. An inverter should also be easier on the printed circuitry, shouldn't it? I could probably just hook up a 1500ah UPS that I have sitting around and be done with it. A generator is in my future but I need to look towards immediate needs on this. The inverter would always be handy. J. |