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RE: mixing batteriy sizes
I have 3 deep cell batteries. One of them is bigger (and newer) than the other 2. What happens if I try to use a big and small one together? What about putting all 3 together?
I hear a lot of "Stuff" like "The weaker battery will draw them down">> Bull droppings.
What will happen is the batteries will work it out.. The Ideal socialist society will be formed (Each according to it's ability, each according to it's needs)
Imagine you have 3 batteries one is 100 AH capacity one 200 one 300
You are drawing 60 amps and you meter each battery
You will find the 100 battery is putting out 10 amps. the middle one 20 and the 300 30.. They work it out. Same when charging.
NOW when batteries age one of two or three things happen and this will affect you ONE of them is "of concern"
First. The internal resistance may go up.. in that case at low current you won't notice it but at higher discharge rates this one will simply not provide as much juice.. when the discharge rate goes down it will likely provide a greater share however for a time till they balance out So this is not a problem.
The second is loss of capacity. also not a problem save the battery basically "Disappears" electrically.
Finally the only concern. A Shorted cell.
OF course this can happen with a battery that's a week old (And did to me once. what's more that battery had a lifetime warranty so the replacement was free). (Pro installed too).
And I have behind me as I type 3 batteries. all different sizes all different ages and that's precisely how they act.
So, will the older, smaller batteries prematurely kill the newest, biggest battery?
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swimmer_spe
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09/13/23 03:19pm |
Tech Issues
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RE: swapping and charging batteries
12.5v after plugging it into the trailer,not into shore power.
I sort of thought that was what you meant But it's not how I'd have said it (hooking up the battery to trailer)
Which is why I covered all options (I hope)
12.5 after sitting on the shelf for a month or even a week is not bad at all. In fact with most meters it's within the margin of error for PERFECT. less you lab calibrated (Gads... Been a lONG time since I lab calibrated a meter)
This one sat at least a year. Could be even longer. I have another that has sat that long that next week I'll be swapping it onto the trailer so it can get a good charge before using it.. Both of these batteries will only be used once a year, for about a week.
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swimmer_spe
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09/13/23 03:18pm |
Tech Issues
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RE: mixing batteriy sizes
OP here.
One thing is, this is only going to be a once a year thing. Basically, I go hunting for a week and may not have access to a generator.
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swimmer_spe
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09/13/23 11:13am |
Tech Issues
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RE: swapping and charging batteries
12.5 after a week of charging is bad. A fully charged battery would be 12.67 or above.
He said 12.5 when he "Plugged it in".. Not sure if he mean plugged the battery into the Trailer or the trailer into 120vac
But 12.5 after a long time on the shelf is actually quite good.
12.5 if trailer plugged into 120v is not good.
Agreed, the original post made it sound like he had left it on the charger for a couple weeks.
If it had been sitting on a shelf for an extended period of time not charging, 12.5v isn't bad.
12.5v after plugging it into the trailer,not into shore power.
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swimmer_spe
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09/13/23 11:06am |
Tech Issues
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RE: swapping and charging batteries
When I plugged it in,it was at 12.5V. I have not charged it since sometime last summer, or the fall before. Not bad...If the battery held 12.5v after sitting for a year... that would generally indicate good condition.
Put them all in use together and see what goes.
12.5 after a week charging is not good. May be marginally OK but not good. Swing by an auto parts store. Most will do a load test for free.
Mixing batteries you get the lowest common denominator so your good battery will be drug down by the marginal battery
12.5v is what it read before charging. I will let it charge for a week and see how it is.
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swimmer_spe
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09/12/23 08:30pm |
Tech Issues
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mixing batteriy sizes
I have 3 deep cell batteries. One of them is bigger (and newer) than the other 2. What happens if I try to use a big and small one together? What about putting all 3 together?
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swimmer_spe
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09/12/23 04:40pm |
Tech Issues
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RE: swapping and charging batteries
When I plugged it in,it was at 12.5V. I have not charged it since sometime last summer, or the fall before. Not bad...If the battery held 12.5v after sitting for a year... that would generally indicate good condition.
Put them all in use together and see what goes.
That is the goal.
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swimmer_spe
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09/12/23 04:37pm |
Tech Issues
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RE: swapping and charging batteries
It's not clear when you saw 12.5 vs plugged it in, but if it was charging then the voltage doesn't reflect battery charge state.
Regardles now that it has charged do a load test to determine the battery condition.
Shore power was disconnected. It jumped to 13.7v once plugged in.
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swimmer_spe
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09/12/23 04:02pm |
Tech Issues
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swapping and charging batteries
I have a 1 year old trailer. It came with a deep cell battery, and it is good. I plan on adding a second battery. I have 2 older ones,that at the time, were good. Today,I swapped out my good battery for one of the older ones to let it change for a week or so with the trailer's charging system. When I plugged it in,it was at 12.5V. I have not charged it since sometime last summer, or the fall before. Not bad...
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swimmer_spe
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09/12/23 02:13pm |
Tech Issues
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RE: Stabilizer jacks at home?
Which is it - stabilizers or jacks? The answer may be different for each.
OP here. I am talking about the jacks that are at all 4 corners that is meant to prevent the trailer from rocking too much.
Since those are designed for stability and not engineered to support the full weight (Like a leveling jack) I would err on the side of caution and leave them up in storage. As others have said, if a tire went flat the weight would be distributed onto the stabilizer and could bend it. Besides, what's to be gained by less rocking on an RV in storage?
..I don't know. I haven't, but I have seen and heard others do it.
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swimmer_spe
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08/09/23 10:53am |
General RVing Issues
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RE: Stabilizer jacks at home?
Which is it - stabilizers or jacks? The answer may be different for each.
OP here. I am talking about the jacks that are at all 4 corners that is meant to prevent the trailer from rocking too much.
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swimmer_spe
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08/08/23 03:29pm |
General RVing Issues
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Stabilizer jacks at home?
If you are parking your trailer for an extended period of time without using it, do you need to drop the stabilizer jacks? If so, why?
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swimmer_spe
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08/07/23 12:54pm |
General RVing Issues
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RE: When to replace the hitch pin?
Any idea what the shear forces required to chop it in two? There are anomalies in this world but betting the farm very few ever are sheared. The receiver welds would probably fail before that pin would shear. I'd sooner keep the one I have road tested than risk a new one these days.
5/8inch pin has a cross sectional area of around 0.30in^2.
It will depend on the specific steel but say we made one of iron (not steel for a worst case scenario). Iron has a shear strength of around 26,000PSI.
So each end of the pin would have a strength of around 7,800 but since both ends would have to shear to get a failure, 15,600lb.
A descent quality steel (nothing exotic) can be twice that shear strength.
Keep in mind, when you tow, you aren't lifting the weight of the trailer. The force needed to pull the trailer is a small fraction of the trailer weight. Even in a panic stop, the trailer would push the truck into a skid long before the force reached the weight of the trailer.
So long as there is no sign of damage or deformation, it should be fine.
Thank you for the math.
Now, what about fatigue? If you bought it brand new and it is used regularly and is 10,20+ years old?
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swimmer_spe
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08/07/23 12:51pm |
Towing
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RE: When to replace the hitch pin?
OP here.
I tend to replace by loosing them. I have yet to have one look rusted or have any marks on it. I also don't like the idea of replacing it only when the safety chains are used.
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swimmer_spe
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08/04/23 03:45pm |
Towing
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When to replace the hitch pin?
The pin for holding the hitch into the receiver is the only real thing holding our trailers to our trucks. Mine is new, but it got me thinking, how often should it be replaced?
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swimmer_spe
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08/03/23 08:13pm |
Towing
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RE: Charging batteries with a small generator
You should be able to camp for days on one battery with a gas refrig.
My experience is that you can get one night per battery. When I camped with one battery, I had to recharge every day. When I upped that to two batteries, I only had to recharge every other day. (Solar greatly extended that however. Later, much later.)
We camp for a weekend regularly on one 12v battery, Friday to Monday. But... we are really careful with it. About the only things the battery is running is the electronics for the frig (gas frig), water pump, and that's about it. We use camping lanterns in the camper, take "Navy" showers, use lights very sparingly.
With y old trailer that had a gas fridge, it could last about that long too.
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swimmer_spe
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06/06/23 08:37am |
Tech Issues
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RE: Charging batteries with a small generator
First, Electric only fridge? 110vac or 12vdc?
There are a lot of 12vdc powered or controlled items in your camper. The converter makes 12vdc from the AC power (shore power or generator) for those items and to charge the battery.
Most people with 12vdc refrigerators find that having two batteries is almost a necessity to insure uninterrupted service when other power is not available in a 24 hour period.
I see there appears to be a big push to have small factory solar power systems installed to keep the batteries topped off with the 12vdc fridges. You might consider adding some solar.
Another issue is that normal lead acid batteries can only be run down 50% to prevent long term damage to the cells. IMO, it’s worth the expense to change to a LiFePO4 battery that can be run down to 0% without damage. And can be had in large power capacity. Just changing out the same capacity LA battery with a Lithium is DOUBLING your usable amps. (Bonus, they weigh 50% less, too.)
It is a 12 v fridge.
I do have plans to upgrade the batteries and add solar at some point. Currently, there is only one battery on it, which it came with when I bought it in the fall. I have an extra battery that is 1 year older. I will be putting that second battery on in the near future. In a few years, I'll be upgrading the solar system by adding more panels (that will be a different thread.) when it comes time to replace the batteries, I plan to replace them with Lithium or whatever is the best at the time I get them. I was just given this 1000w generator for free, so I figure I will use it till I can do the upgrades, including a bigger generator.
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swimmer_spe
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06/05/23 11:57am |
Tech Issues
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RE: Charging batteries with a small generator
OP here.
If while the generator is running, I turn off the fridge (pulling the fuse if need be) would that give me a better charge?
If the generator is able to power both the fridge and the converter (rv speak for battery charger) then shutting off the fridge will make no difference except for a tiny bit more fuel used.
Assuming it's a 12v fridge, the generator will only see the battery charger load.
It is a 12 v fridge.
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swimmer_spe
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06/05/23 11:52am |
Tech Issues
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RE: Charging batteries with a small generator
Is there any way you can get a gas refrig installed? Seems like that would make everything easier. You should be able to camp for days on one battery with a gas refrig.
Speaking of which - what about heating the camper? If you have an onboard forced air gas heater, the blower can use more power than you might think. If you have an electric heater - your battery may not last the night.
Cannot switch out the fridge.
Furnace is forced gas.
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swimmer_spe
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06/05/23 11:51am |
Tech Issues
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RE: Charging batteries with a small generator
Swimmer,
You have a wonderful collection of inadequate information for your responses.
First problem: Lead Acid Flooded batteries can be charged to about 90% State of Charge (SOC) in a couple of hours depending on the battery temperature. That last 10% takes most of five hours and can't happen faster without the heat damaging the battery.
Second problem: That 1000w generator is about 60 amps at 13.5V (for a 12V system). Your electric refrigeration is probably about 120W (about 10 amps) on a duty cycle that is related to temperature and use. So, it will suffice and larger generator won't get you any advantage.
Third problem: Will you be able to run the generator all the time you need where you are going? Many places have quiet hours.
My guess based on my experience is that if you run the generator at least 12 hours a day, you should be able to survive.
You gave us no clue what the reefer is or what your house bank is, and it does not make a huge difference.
If you know more, come back and we can probably get you a better answer.
I plan on using it when hunting on crown land. So, if need be, it can be run nonstop.My plan is to fire it up when we get up, and leave it running till we get back from hunting.
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swimmer_spe
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06/04/23 07:16pm |
Tech Issues
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