I'm headed out to NASCAR tomorrow morning, which means 2 1/2 days of dry camping. Last year the fridge quit working on propane (okay, I broke it) so I had to run the generator 24x7 to keep the fridge on. After less than 12 hours, however, the genny quit too.
I got everything fixed and working again, but in the meantime I also bought a 2,000 watt inverter. I figure I can run small stuff (boom box, phone chargers, etc.) on it without running the 6,500 watt generator.
I get a pretty big arc at the battery when I first connect it. I've read this is normal. My first question is whether there's any draw from the inverter if nothing is plugged into it (other than the little green LED light)?
Second, and this is more of an observation, I have one of those extension cords with multiple receptacles, each with a little LED light. When plugged into the inverter, the lights don't light up but I still have power. Interesting.
Third, and this might be more hypothetical, if I were need to switch the fridge to 120V how long could I keep it on before recharging the batteries? It has a 300W heating element (2.5 amp draw) and I have 2 12V deep-cycle batteries (3 if you count the chassis battery, but it's isolated so I do have a backup). They're in good shape and fully charged (or will be after the drive there). I can keep an eye on the battery monitor, but I need a ball park - minutes, hours, days....
I got everything fixed and working again, but in the meantime I also bought a 2,000 watt inverter. I figure I can run small stuff (boom box, phone chargers, etc.) on it without running the 6,500 watt generator.
I get a pretty big arc at the battery when I first connect it. I've read this is normal. My first question is whether there's any draw from the inverter if nothing is plugged into it (other than the little green LED light)?
Second, and this is more of an observation, I have one of those extension cords with multiple receptacles, each with a little LED light. When plugged into the inverter, the lights don't light up but I still have power. Interesting.
Third, and this might be more hypothetical, if I were need to switch the fridge to 120V how long could I keep it on before recharging the batteries? It has a 300W heating element (2.5 amp draw) and I have 2 12V deep-cycle batteries (3 if you count the chassis battery, but it's isolated so I do have a backup). They're in good shape and fully charged (or will be after the drive there). I can keep an eye on the battery monitor, but I need a ball park - minutes, hours, days....
Mel B. wrote:
One word SOLAR!
Mel
Yes I'm going to look into that next. I've had some success at home with outdoor surveillance cameras and a 100W panel charging a smallish 12V battery. I have a stepdown transformer to go from 12V to 5V for the USB. I'd have to do the math on my boondocking usage, but I'm thinking that 100W panel would keep the batteries charged with our somewhat limited usage.
pianotuna wrote:
Hi,
Sounds as if it may be a MSW (modified sine wave) inverter. Hence the circuit for powering the led lights on the octopus cord don't work.
For the small stuff get a 300 watt PSW inverter. DO NOT ATTEMPT TO USE THE MSW INVERTER WITH APPLE PRODUCTS.
If you have a battery charger, I would drag it along and use it in conjunction with the converter to reduce generator run time for battery charging.
Have a great time at the races.
Thanks! It is a cheap MSW inverter. I do have a battery charger but I didn't bring it. We had a great time. This is our 4th time out and the weather got worse each year, culminating with a microburst last year that nearly toppled the camper and sent sheets of sideways rain shooting through every vent and crevice on the rig. But - this weekend was near perfect. We had a little rain early Saturday morning and that was it.
Anyhow, back to the subject at hand. I ran the fridge on propane all 3 days. I couldn't get the ignitor to stop igniting at first. After a few hours of click click clicking, the wire started to melt. I repositioned the probe and tightened a loose connection and it was fine. So that removed a big part of the electric equation.
time2roll made a comment about a 300 watt inverter. I forgot I had one - I found it in a cabinet just before we left. It powered the boom box, phone chargers, satellite receiver and TV - *almost* all at once. I got an over-voltage alarm when I first fired up the TV but it didn't shut off. Removing the boom box made it happy again.
I ran everything off that little inverter - never got the big one out. On the 2nd day the girls needed to run hair dryers and whatnot so I fired up the generator. The batteries had only gotten down to 3/4 and that put them back up to 100%. And this is obviously after use beyond just the inverter like lights (I've gone 100% LED), water pump, bathroom fans, etc. When I left yesterday they were 3/4 again. I fired up the generator anyway because I wanted to run the rooftop A/C on the way home.
So long story short, there's a decent amount of electrical capacity when being sensible about what I'm using it for. I guess using the fridge on 120V was never a realistic option with my setup, and I'm glad I didn't try.
Thanks all!
Chris Bryant wrote:
That's 2.5 amps at 120 volts- more like 30 amps at 12 volts, so like 3 hours, using the above figures.
Thanks both for the replies.
Yes - forgot to convert back to 12V.
They are 109 amp-hour batteries. And yeah, with the other phantom loads probably a lot less time available. I guess long story short I shouldn't depend on the inverter for the fridge. The TV is LED, and the satellite receiver can't draw much...but it all adds up. The big draw would be the fridge, which I'm thinking I'm going to forget about. I'll just run the generator if the propane fails.
