Last year while hunting I had some issues with my electrical system keeping the heater running all night. Normally would not have been an issue but we had a major snow storm move through the state and it got colder than normal for that time of the year. I sent some emails to Bob and asked for some suggestions here. I have decided to go with a Solar set up. Unfortunately I cant afford to do it all at once. I bought 4 CROWN 260 AMP-Hour Deep Cycle 6 Volt Batteries, CR-260 to start. Found a good deal on them from a nearby distributor and had a friend pick them up to save shipping. They still cost about $500. I want to set up a temporary system for this years hunting season. My question is I want to run a charger off my Generator during the day that will charge 2 of the batteries at a time while running the Camper System on the other 2. I think part of my problem last year was trying to charge the system while the furnace was draining the batteries and it could never catch up since the campers charge isnt that great anyway. I need to get an actual charger to plug into my generator that will charge 2 of the batteries independently of the camper without doing any damage to them. Will any automotive charger work or do I need something better for these kinds of batteries? My Plan is to swap out the batteries every morning. Charge up the 2 that ran the system the previous day and night and run the system off the 2 freshly charged ones. My big fear is somehow ruining $500 in batteries before I can buy the stuff to set up my solar system. Any and all advice is greatly appreciated.
Upgrading electrical system On Travel Trailer
- Thread starter Samorkand
- Start date
Any recommendations on Model? I want to avoid charging all 4 at the same time. My fear is the batteries wont be able to fully charge if the Furnace and Camper electrical is using power while the charger is charging. I may be completely wrong about this though. I figured charging 2 at a time while running off a freshly charged 2 would be better. Anyone have a better thought on this?
I am not too sure on the model but what you want is as big ah as you can afford and look for the maximum amperage output... If you use more then that while using your equipment then the charger won't charge
Your looking around the 20 to 50 max amp output I think
Unless you have alot of solar panels you will not be able to beat the charger 100w of power will give you around 8 amps on the best conditions
Your looking around the 20 to 50 max amp output I think
Unless you have alot of solar panels you will not be able to beat the charger 100w of power will give you around 8 amps on the best conditions
dwh
Tail-End Charlie
You gotta lotta issues here buddy. 
Okay first of all, it would be better to use just one big bank, than to split it into two smaller banks. The reason is this thing called the Peukert Effect. Basically, the larger the load is, the faster the batteries go dead.
Now that sounds like perfect sense, but it doesn't mean exactly what it sounds like. Let's say you've got a 10a load on a 100a battery. Okay, that battery can run that load for 10 hours. But say you drop the load to a 5a load - the battery will run that load for *more than* 20 hours. Double the load to 20a, and the battery will run it for *less than* 5 hours. It's a sliding scale.
The way that works out, is that if you double the battery bank size, but don't double the load, you'll get *more than* double the run-time out of the battery bank.
Your next issue is charging. You don't have to disconnect batteries from load while charging IF you have a big enough charger. Say you have a 50 amp charger, and 20a of loads running. Well, the charger will supply those 20a of loads and still put 30a into the batteries.
Now, doing a little quickie net research, from your description, I'm guessing you got the Crown CR-260 batteries. The Crown manual says:
"Crown Battery recommends electronically controlled automatic chargers that are programmed to deliver a high constant current rate of 12 to 18 amperes per 100 ampere-hours (20 Hour Rating) of battery capacity."
https://www.crownbattery.com/en/wp-content/uploads/2013/09/Deep-Cycle-Product-Support-Broch.pdf
Which means first of all that no, you can't use a standard benchtop automotive charger - those are constant voltage, and you need one that can do constant current. Oh, the automotive charger will get the job done eventually, but not good enough, not fast enough.
Battery companies always specify the size charger (amount of current) based on the capacity of the battery or bank. They usually say something like C (in this case, that means "battery capacity" - not "the speed of light" ) divided by 4 or C/4. In Crown's case, they are recommending between C/8 and C/5. Let's say you rig two of those 6v 260ah batteries in series to get 12v. Now you have a 12v 260ah battery. Well the minimum charger you need is going to be C/8 or 260/8 = 32a. You'd be a LOT better off going to the max though. That would be 260/5 = 52a. So you need AT LEAST a 30a CONSTANT CURRENT charger, but you'd be better off with a 50a.
Double that if you rig all 4 into a single bank.
If you DON'T follow the minimum recommendations, you WILL shorten your batteries' life.
If you are going to charge at the same you are running loads, then you need to add the loads as well, so say you need a minimum 30a charger and you've got 20a of loads running while you are charging - now you need a 50a charger just to meet the battery's minimum charging requirements.
The next question is will your generator run that charger? Dunno what you've got. For example, a Honda eu2000i is rated for 1600w continuous load.
1600w / 120v = 13a.
An Iota DLS-55 will pull just over 13a on the 120v side under full load. So yea, a phased plasma rifle...er...I mean...a generator <Arnold Terminator voice> "in the 2000 watt range" will supply a 50a charger.
So what sort of charger are you going to need? Computer controlled 3-stage which can do a constant current bulk stage (gets the battery to around 80% charger as quick as possible) and then can do a constant voltage absorb stage (to push it up that last 20% - which will take like 8 hours) and then drops to a float or maintenance stage).
I would recommend the Iota with IQ/4 brain module. The reason is, that while Crown recommends taking the battery to 14.5v, the Iota with IQ/4 will take it up to 14.8v. This will A) get the battery charged a little quicker, and B) get a little more charge into the battery. The down side is that you'll use a bit more water so will need to keep an eye on water levels. But with 500 bucks worth of batteries, you better be keeping an eye on them anyway if you want them to live as long as possible.
I would say go with a DLS-75 in order to supply loads and still get the full 50a into the batteries:
http://www.iotaengineering.com/dls75.htm
But the 75 draws as high as 18a under full load and you'd need a generator in the 3000w range to feed it.
The DLS-55 draws just over 13a under full load, and that's right at the max a Honda eu2000i puts out. In other words, a perfect match.
http://www.iotaengineering.com/dls55.htm
Iota DLS-55 with the IQ/4 brain module will run you 180 bucks at Northern Arizona Wind & Sun. (Note on that page, it shows 160 bucks until you choose the option below the price to add the brain module). You might find it a bit cheaper by looking around but NAWS has been around the longest and has just about the best rep.
DLS-75 with IQ/4 will run you around 290 bucks:
http://www.solar-electric.com/batte...12-volt-75-amp-regulated-battery-charger.html
Again, if you "did it right" and rigged all 4 batteries into a single bank, you'd need double the charger amps and double the generator. What I'm saying here is based on rigging a pair of those CR-260s into a 12v 260ah bank.
Now...solar.
Let's say you rigged for a 12v 260ah bank. Let's also say you draw the bank down 50% (the max if you want the battery to have a halfway decent lifespan). That means you've got to supply 130ah to get it recharged. Actually batteries aren't 100% efficient, so you'll need to supply 20% more amps than you took out in order to get it back to a full charge. So you gotta supply 166a to get it back to full.
So how much solar do you need? Well 166a x 14.5v (battery max) = 2407w. Now let's spread that over say 6 hours of good strong sun in a day (and that's actually a bit optimistic) - 2400w / 6 = 400w. So you're going to need at least a 400w solar array if you want to have a prayer of keeping up with your daily consumption (if you draw down 50% overnight).
Okay first of all, it would be better to use just one big bank, than to split it into two smaller banks. The reason is this thing called the Peukert Effect. Basically, the larger the load is, the faster the batteries go dead.
Now that sounds like perfect sense, but it doesn't mean exactly what it sounds like. Let's say you've got a 10a load on a 100a battery. Okay, that battery can run that load for 10 hours. But say you drop the load to a 5a load - the battery will run that load for *more than* 20 hours. Double the load to 20a, and the battery will run it for *less than* 5 hours. It's a sliding scale.
The way that works out, is that if you double the battery bank size, but don't double the load, you'll get *more than* double the run-time out of the battery bank.
Your next issue is charging. You don't have to disconnect batteries from load while charging IF you have a big enough charger. Say you have a 50 amp charger, and 20a of loads running. Well, the charger will supply those 20a of loads and still put 30a into the batteries.
Now, doing a little quickie net research, from your description, I'm guessing you got the Crown CR-260 batteries. The Crown manual says:
"Crown Battery recommends electronically controlled automatic chargers that are programmed to deliver a high constant current rate of 12 to 18 amperes per 100 ampere-hours (20 Hour Rating) of battery capacity."
https://www.crownbattery.com/en/wp-content/uploads/2013/09/Deep-Cycle-Product-Support-Broch.pdf
Which means first of all that no, you can't use a standard benchtop automotive charger - those are constant voltage, and you need one that can do constant current. Oh, the automotive charger will get the job done eventually, but not good enough, not fast enough.
Battery companies always specify the size charger (amount of current) based on the capacity of the battery or bank. They usually say something like C (in this case, that means "battery capacity" - not "the speed of light"
) divided by 4 or C/4. In Crown's case, they are recommending between C/8 and C/5. Let's say you rig two of those 6v 260ah batteries in series to get 12v. Now you have a 12v 260ah battery. Well the minimum charger you need is going to be C/8 or 260/8 = 32a. You'd be a LOT better off going to the max though. That would be 260/5 = 52a. So you need AT LEAST a 30a CONSTANT CURRENT charger, but you'd be better off with a 50a.Double that if you rig all 4 into a single bank.
If you DON'T follow the minimum recommendations, you WILL shorten your batteries' life.
If you are going to charge at the same you are running loads, then you need to add the loads as well, so say you need a minimum 30a charger and you've got 20a of loads running while you are charging - now you need a 50a charger just to meet the battery's minimum charging requirements.
The next question is will your generator run that charger? Dunno what you've got. For example, a Honda eu2000i is rated for 1600w continuous load.
1600w / 120v = 13a.
An Iota DLS-55 will pull just over 13a on the 120v side under full load. So yea, a phased plasma rifle...er...I mean...a generator <Arnold Terminator voice> "in the 2000 watt range" will supply a 50a charger.
So what sort of charger are you going to need? Computer controlled 3-stage which can do a constant current bulk stage (gets the battery to around 80% charger as quick as possible) and then can do a constant voltage absorb stage (to push it up that last 20% - which will take like 8 hours) and then drops to a float or maintenance stage).
I would recommend the Iota with IQ/4 brain module. The reason is, that while Crown recommends taking the battery to 14.5v, the Iota with IQ/4 will take it up to 14.8v. This will A) get the battery charged a little quicker, and B) get a little more charge into the battery. The down side is that you'll use a bit more water so will need to keep an eye on water levels. But with 500 bucks worth of batteries, you better be keeping an eye on them anyway if you want them to live as long as possible.
I would say go with a DLS-75 in order to supply loads and still get the full 50a into the batteries:
http://www.iotaengineering.com/dls75.htm
But the 75 draws as high as 18a under full load and you'd need a generator in the 3000w range to feed it.
The DLS-55 draws just over 13a under full load, and that's right at the max a Honda eu2000i puts out. In other words, a perfect match.
http://www.iotaengineering.com/dls55.htm
Iota DLS-55 with the IQ/4 brain module will run you 180 bucks at Northern Arizona Wind & Sun. (Note on that page, it shows 160 bucks until you choose the option below the price to add the brain module). You might find it a bit cheaper by looking around but NAWS has been around the longest and has just about the best rep.
DLS-75 with IQ/4 will run you around 290 bucks:
http://www.solar-electric.com/batte...12-volt-75-amp-regulated-battery-charger.html
Again, if you "did it right" and rigged all 4 batteries into a single bank, you'd need double the charger amps and double the generator. What I'm saying here is based on rigging a pair of those CR-260s into a 12v 260ah bank.
Now...solar.
Let's say you rigged for a 12v 260ah bank. Let's also say you draw the bank down 50% (the max if you want the battery to have a halfway decent lifespan). That means you've got to supply 130ah to get it recharged. Actually batteries aren't 100% efficient, so you'll need to supply 20% more amps than you took out in order to get it back to a full charge. So you gotta supply 166a to get it back to full.
So how much solar do you need? Well 166a x 14.5v (battery max) = 2407w. Now let's spread that over say 6 hours of good strong sun in a day (and that's actually a bit optimistic) - 2400w / 6 = 400w. So you're going to need at least a 400w solar array if you want to have a prayer of keeping up with your daily consumption (if you draw down 50% overnight).
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Wow I really appreciate all the info you gave.
My intention was to run the generator during the day while we are out hunting. Hopefully when I get back everything will be charged up. The only thing that would be running would be the furnace and I plan to lower the temp so it won't run as much. So I think the 55 Amp charger would work fine. I have 2 generators a 3500 watt,i cant remember the name off hand, i got from Cabelas and a Hyundai Y2000si 2200-Watt Portable Inverter Generator. Hyundai says it will put out 2000 watts continuous. I usually use the Hyundai. I take both just incase one has any issues. I did find one of the 55 amp charger with the module for $169 on Amazon.
My intention was to run the generator during the day while we are out hunting. Hopefully when I get back everything will be charged up. The only thing that would be running would be the furnace and I plan to lower the temp so it won't run as much. So I think the 55 Amp charger would work fine. I have 2 generators a 3500 watt,i cant remember the name off hand, i got from Cabelas and a Hyundai Y2000si 2200-Watt Portable Inverter Generator. Hyundai says it will put out 2000 watts continuous. I usually use the Hyundai. I take both just incase one has any issues. I did find one of the 55 amp charger with the module for $169 on Amazon.
Joe917
Explorer
As dwh says do not split the bank. Depth of discharge is a bigger factor than number of discharges when it comes to battery life.
Do not buy a cheap automotive charger. You need a 4 stage charger with the ability to equalize. The Crowns will need periodic equalization.
I am running the same size bank but with Trojans instead of Crowns. You need a 100amp charger for that battery bank, I am running a 125 amp Magnum inverter charger .(dwh's 50 amps is for 260 amphrs).
630 watts of solar keep charger use to a minimum.
CTEK does not make anything suitable for a battery bank of this size.
Do not buy a cheap automotive charger. You need a 4 stage charger with the ability to equalize. The Crowns will need periodic equalization.
I am running the same size bank but with Trojans instead of Crowns. You need a 100amp charger for that battery bank, I am running a 125 amp Magnum inverter charger .(dwh's 50 amps is for 260 amphrs).
630 watts of solar keep charger use to a minimum.
CTEK does not make anything suitable for a battery bank of this size.
dwh
Tail-End Charlie
No worries. But...I just noticed that somehow the vBulletin editor lost about half the bloody post...
I fixed it, so go back and read it again to see the bits that got sent into the ether by vBulletin.
At this time I cant afford the Magnum Charger. Possibly next year when I can buy the Solar panels. I'm really thinking I should have only bought 2 of the Crown batteries to begin with. I actually got the Batteries for free so to speak. My ex brother inlaw lives with me and I got him to buy them for rent. My boss has an Amp Clamp and I am going to fire up the furnace to see what kind of amp draw it has.
dwh
Tail-End Charlie
Yea, that's also true. The double size bank will have a lower DoD and thus have a longer lifespan (number of cycles).
OH D'OH! Nice catch. I did forget about the EQ (so used too thinking in terms of sealed batteries lately) - and the Iota doesn't do an EQ.
So yea Samorkand - you're better off to get one that can do 3-stage charging + EQ. Magnum is good but looking on their web site, I only see inverter/chargers but no just plain chargers,
Xantrex is also good. A 60a Truecharge 2 would be sexy. Also the new ones allow you tie two together to get 120a if you decided to go with the bigger bank.
Not cheap though. Cost more than the battery bank...
http://www.amazon.com/xantrex-TRUE-Charge-Battery-Charger/dp/B009UCAD5G
dwh
Tail-End Charlie
And because I can see the next question coming...
No, you don't actually need an EQ most of the time.
Battery Equalization (which should NEVER be done to a sealed battery) is "a timed, controlled overcharge". Basically, you fully charge the battery, and then take it up to a certain over-voltage (whatever the manufacturer recommends) and hold it there for a certain amount of time (again, whatever they recommend).
Technically, an EQ is only supposed to be done as a troubleshooting measure IF you find that your cells' specific gravity are not all the same after giving the battery a full charge.
You overcharge the battery to try and force the low cell(s) to come up and be equal to the rest of the cells. It's NOT a normal maintenance procedure - it's an occasional "if needed" procedure.
Now, there are a few battery chargers out there that say they do umpty gazillion "charge stages" and sometimes they'll call one of those stages "equalization". Progressive Dynamics does that sort of BS. What they call equalization, is really just raising the battery up to 14.4v and holding it there for 15 minutes. It'll do that every 21 hours when floating on shore power. It's not a real EQ.
http://www.progressivedyn.com/prod_details/charge_wizard.html
Technically, the Progressive Dynamics with Charge Wizard is just a 2-stage charger - bulk and then straight to float. It does have two different float stage constant voltage set points, but they are NOT different stages - they are just floating but at a couple different voltages.
Hell, even Iota is guilty of a little EQ marketing BS.
http://www.iotaengineering.com/iq.htm
The IQ/4 does NOT do a true EQ. It just triggers a run-through of the normal "bulk/absorb and back to float" program after 7 days sitting at float.
To get really technical - just about EVERYONE is guilty of marketing BS. The truth is that ONLY bulk and absorb are truly "charging stages". Float is NOT a charging stage - it's a maintenance stage. EQ is a once in a while maintenance procedure.
An Iota without the brain is just a "2-stage" charger - it runs bulk up to 14.6v and then drops straight to float. The Progressive Dynamics does the same thing, but will drop the float voltage to a lower level after a set time.
But TECHNICALLY - those are SINGLE STAGE chargers. They only have ONE charging stage. Float is NOT a charging stage.
A so-called "3-stage" charger - bulk/absorb/float is TECHNICALLY a 2-stage charger, because it has both bulk and absorb charging stages + float for maintenance.
But yea...whatever. What is called a "4-stage" is usually a "3-stage" (bulk/absorb/float) + EQ. Though in truth, neither float or EQ is a charging stage.
No, you don't actually need an EQ most of the time.
Battery Equalization (which should NEVER be done to a sealed battery) is "a timed, controlled overcharge". Basically, you fully charge the battery, and then take it up to a certain over-voltage (whatever the manufacturer recommends) and hold it there for a certain amount of time (again, whatever they recommend).
Technically, an EQ is only supposed to be done as a troubleshooting measure IF you find that your cells' specific gravity are not all the same after giving the battery a full charge.
You overcharge the battery to try and force the low cell(s) to come up and be equal to the rest of the cells. It's NOT a normal maintenance procedure - it's an occasional "if needed" procedure.
Now, there are a few battery chargers out there that say they do umpty gazillion "charge stages" and sometimes they'll call one of those stages "equalization". Progressive Dynamics does that sort of BS. What they call equalization, is really just raising the battery up to 14.4v and holding it there for 15 minutes. It'll do that every 21 hours when floating on shore power. It's not a real EQ.
http://www.progressivedyn.com/prod_details/charge_wizard.html
Technically, the Progressive Dynamics with Charge Wizard is just a 2-stage charger - bulk and then straight to float. It does have two different float stage constant voltage set points, but they are NOT different stages - they are just floating but at a couple different voltages.
Hell, even Iota is guilty of a little EQ marketing BS.
http://www.iotaengineering.com/iq.htm
The IQ/4 does NOT do a true EQ. It just triggers a run-through of the normal "bulk/absorb and back to float" program after 7 days sitting at float.
To get really technical - just about EVERYONE is guilty of marketing BS. The truth is that ONLY bulk and absorb are truly "charging stages". Float is NOT a charging stage - it's a maintenance stage. EQ is a once in a while maintenance procedure.
An Iota without the brain is just a "2-stage" charger - it runs bulk up to 14.6v and then drops straight to float. The Progressive Dynamics does the same thing, but will drop the float voltage to a lower level after a set time.
But TECHNICALLY - those are SINGLE STAGE chargers. They only have ONE charging stage. Float is NOT a charging stage.
A so-called "3-stage" charger - bulk/absorb/float is TECHNICALLY a 2-stage charger, because it has both bulk and absorb charging stages + float for maintenance.
But yea...whatever. What is called a "4-stage" is usually a "3-stage" (bulk/absorb/float) + EQ. Though in truth, neither float or EQ is a charging stage.
dwh
Tail-End Charlie
Heh, I was already writing the response to that question before you wrote the question!
Don't ask how that's done - it's a Jedi Master thing and you're not yet cleared for that information.
I'm starting to think maybe I over did things. Originally all I wanted was to be able to run my furnace all night. I had no idea I was looking at another $1k to even start to get this to work. I head up on the mountain the 15th of next month. Looks like Ill have to wing it with the 2 12v batteries I have from last year. To be honest I may look into selling those Crown Batteries.
If I just buy a Charger and hook it up to my 2 12 volt batteries while they are hooked up to the existing 12volt camper system will it have any negative effects on the camper charger? I hope that made sense. From what I have read the camper system is more of a maintainer than a charger and wont charge the batteries the way I need it to. So by leaving the batteries hooked up and running the furnace will I hurt anything buy buying a Iota charger and hooking it up at the battery? That way my furnace runs and I can charge the batteries?
If I just buy a Charger and hook it up to my 2 12 volt batteries while they are hooked up to the existing 12volt camper system will it have any negative effects on the camper charger? I hope that made sense. From what I have read the camper system is more of a maintainer than a charger and wont charge the batteries the way I need it to. So by leaving the batteries hooked up and running the furnace will I hurt anything buy buying a Iota charger and hooking it up at the battery? That way my furnace runs and I can charge the batteries?