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Zoomschwortz 04-22-2020 10:03 AM

Batteries and WFCO WF-8955PEC questions.
 
I have a 2014 ORV 20FQ TT that has a 3 stage WFCO WF-8955PEC converter/charger.


I am in the process of adding 4 GC2 230ah 6 volt batteries for a total of 460ah.


Question:
If I drain batteries to 50% and need to replenish the 230ah, will the WF-8955PEC be up to the task of recharging the batteries in a reasonable time while using a Honda eu2200i generator?


Would it be faster and better for me to power a stand alone battery charger to recharge the batteries?


If a stand alone charger would be better, can you recommend good charger options?


Thanks
Ken

twinboat 04-22-2020 10:59 AM

If you use 50% or 230 AH of battery, you need to replace that + about 20%. That figures out to roughly 280 AH.

If you have a 50 amp charger, thats just short of 6 hours of charging. 50 amps X 6 hours = 300 AH.

Add a second 50 amp charger and it may overload the eu2000 in the beginning

My eu2000 handled a IOTA 55 amp charger and a 20 amp charger. Still needed over 4 hours of running it. I let it run out of gas at around 5 hours on a 600 AH battery bank.

Mark_K5LXP 04-22-2020 01:08 PM

Quote:

Originally Posted by Zoomschwortz (Post 5234531)
will the WF-8955PEC be up to the task of recharging the batteries in a reasonable time

What's "reasonable"?

Quote:

Would it be faster and better for me to power a stand alone battery charger to recharge the batteries?
GC-2's are spec limited to around 20A charge current, a parallel set would be 40A. You can charge harder if you've got the converter for it but it's harder on the batteries and it's not one for one - say doubling charge current doesn't halve the charge time (peukert works both ways). After bulk the rest of the charge cycle takes as long as it takes, it's a function of time. It might be "reasonable" to only run long enough to restore bulk amps for a few days then allow an absorb phase to complete when you're running the genset for a longer period anyway like A/C during the day. Solar is great if you have it for finishing off a charge cycle as it's silent and it doesn't take a lot of power, just time.

Mark B.
Albuquerque, NM

Zoomschwortz 04-22-2020 01:13 PM

Quote:

Originally Posted by twinboat (Post 5234609)
If you use 50% or 230 AH of battery, you need to replace that + about 20%. That figures out to roughly 280 AH.

If you have a 50 amp charger, thats just short of 6 hours of charging. 50 amps X 6 hours = 300 AH.

Add a second 50 amp charger and it may overload the eu2000 in the beginning

My eu2000 handled a IOTA 55 amp charger and a 20 amp charger. Still needed over 4 hours of running it. I let it run out of gas at around 5 hours on a 600 AH battery bank.

Thank you for your reply and information.

Will it be unreasonable for me to expect my WF-8955pec to actually deliver 55amps (or close to it) to my batteries?

Multiple chargers:
If my 8955pec is bulk charging @ 14.4 vdc and I attach another 3 or 4 stage charger, would the 2nd charger detect the 14.4 vdc from the 1st charger and be tricked into thinking that the batteries are near to full charge and skip over to abortion mode or would both chargers charge in bulk mode until the batteries are really near full charge?

I should probably get a battery monitor. I would like one that will show amps in, amps out and state of charge or amps left in batteries.
Are there any good quality, easy to use monitors for $100 or less that you would recommend?

Thanks again.
Ken

Zoomschwortz 04-22-2020 01:36 PM

Quote:

Originally Posted by Mark_K5LXP (Post 5234789)
What's "reasonable"?

GC-2's are spec limited to around 20A charge current, a parallel set would be 40A. You can charge harder if you've got the converter for it but it's harder on the batteries and it's not one for one - say doubling charge current doesn't halve the charge time (peukert works both ways). After bulk the rest of the charge cycle takes as long as it takes, it's a function of time. It might be "reasonable" to only run long enough to restore bulk amps for a few days then allow an absorb phase to complete when you're running the genset for a longer period anyway like A/C during the day. Solar is great if you have it for finishing off a charge cycle as it's silent and it doesn't take a lot of power, just time.

Mark B.
Albuquerque, NM

Thank you for your help and information.

Well, the longer my generator is running, the longer I need to stay with the trailer, so, reasonable to me would be around 4 hours.

My trailer came with an almost useless 10w solar panel.
I live in Western Washington, so, a week of cloudless skyís can be rare. Considering that most days would be lead colored skyís or raining, how many watt solar panel system would you recommend for my battery bank?

Is it okay to run solar and a charger at the same time?

Back to generator only for charging:
On warm nights, I would use fewer ah than on cold nights.
Letís say that I have a week of warm weather and use 60 ah every 24 hours. For wet cell lead deep cycle batteries, would I be better to fire up the generator every morning or should I just run the generator every 3-4 day as I get close to the 50% mark?

Thanks again
Ken

twinboat 04-22-2020 02:56 PM

Batteries have so many cycles in them. The deeper the cycle the less of them you get.

You can double their life by only going down to 75% compared to 50%.

You cut their life in half if you draw them down to 10% compared to 50% discharge.

As far as charging, when your in bulk mode, the charger is outputting full rated amps at battery voltage, not 14.6 volts. As the batteries charge the voltage slowly climbs.

Once the batteries voltage climbs to 14.6 volts, the charger or chargers enter absorb mode and hold 14.6 volts as the amps drop off. By that time, you don't need both chargers because the batteries are at 80% state of charge.

SteveJ. 04-22-2020 03:20 PM

https://batteryuniversity.com

Zoomschwortz 04-22-2020 03:38 PM

Quote:

Originally Posted by twinboat (Post 5234905)
Batteries have so many cycles in them. The deeper the cycle the less of them you get.

You can double their life by only going down to 75% compared to 50%.

You cut their life in half if you draw them down to 10% compared to 50% discharge.

As far as charging, when your in bulk mode, the charger is outputting full rated amps at battery voltage, not 14.6 volts. As the batteries charge the voltage slowly climbs.

Once the batteries voltage climbs to 14.6 volts, the charger or chargers enter absorb mode and hold 14.6 volts as the amps drop off. By that time, you don't need both chargers because the batteries are at 80% state of charge.

Thank you. This helps.

Zoomschwortz 04-22-2020 03:39 PM

Quote:

Originally Posted by SteveJ. (Post 5234922)

Thank you, I will check this out.

Clomok 04-22-2020 11:26 PM

You honestly wonít get much more then 15 amps charge current out of that 8955, id swap it to a Progressive Dynamics 9260, iota, or bondocker 60 amp converter. They will actually go through the 3/4 charge cycles and give you a real world charging capability.

Zoomschwortz 04-22-2020 11:38 PM

Quote:

Originally Posted by Clomok (Post 5235421)
You honestly wonít get much more then 15 amps charge current out of that 8955, id swap it to a Progressive Dynamics 9260, iota, or bondocker 60 amp converter. They will actually go through the 3/4 charge cycles and give you a real world charging capability.

Thank you, I will check them out.

I need to invest in a battery monitor so I can easily see how much is going into and out of my batteries.

Thanks again
Ken

Mark_K5LXP 04-23-2020 11:52 AM

Quote:

Originally Posted by Zoomschwortz (Post 5234940)
Will it be unreasonable for me to expect my WF-8955pec to actually deliver 55amps (or close to it) to my batteries?

It will, when they're really low. But it won't deliver 55A all the way until the point it switches to absorb mode. Between cables, battery terminal and internal resistance, the current will taper off as the battery voltage starts to come up. So don't count on 55A times X minutes gets you from one SOC point to another, it's not linear.

Quote:

reasonable to me would be around 4 hours. ... Letís say that I have a week of warm weather and use 60 ah every 24 hours. ... would I be better to fire up the generator every morning or should I just run the generator every 3-4 day as I get close to the 50% mark?
"Better" for you would be to run the genset once every 3-4 days. "Better" for the batteries is to keep them as close to 100% SOC as you can. I run the genset in the morning and the evening. If it's hot and I run the A/C in the afternoon that counts as the evening run. Point being is that you don't have to block out a regimented time to do this, just run however long you need to whenever you're there anyway. If you're over 80% I probably wouldn't bother running the genset unless I needed it for something else. I don't ascribe to the "50% rule" so will use up what I have if circumstances dictate. In the interest of "making hay while the sun shines" and not so much battery happiness it's a good idea to keep them as charged as you can just in case something comes up you need the extra run time or power.

Quote:

If my 8955pec is bulk charging @ 14.4 vdc and I attach another 3 or 4 stage charger,
would the 2nd charger detect the 14.4 vdc from the 1st charger and be tricked into thinking
that the batteries are near to full charge and skip over to [absorption] mode
What I think would happen is the 2nd charger would apply charge current, the terminal voltage would bump up and both chargers would switch to absorption mode. Some chargers may have a hold time before switching, some might wait for a particular current taper. Hard to say when you're talking two different chargers.

You can always turn up the absorption threshold voltage or disable it entirely, and just cram bulk amps into them until they're "full". At elevated voltages (what you'd need to have to keep higher currents flowing) a portion of that charge energy will be used to dissolve water, generate heat and damage the plates. So careful how hard you want to push it - you'll return Ah 'quicker' but the life of your batteries will be 'shorter'.

Quote:

I should probably get a battery monitor.
Yep.

Quote:

I would like one that will show amps in, amps out and state of charge or amps left in batteries.
Some better than others, ones like the Victron and Trimetric are pretty good. They crunch operating parameters on the fly and give some pretty accurate numbers. More than $100 though. I use one of the $20 amazon ones, they tell you all you need to really know for day to day operating. The statistics, history and predictive values the fancy ones offer is curious and interesting but frankly I don't care. I run the stuff I want, and charge up when I can. At the end of the day that's all batteries need to do.

During outings I don't worry too much about getting through an absorb phase and the only lower limit I watch is never go below 10.5V under load. If I was doing this for extended periods (months at a time) this would take it's toll on the batteries but for a few weeks a year and rarely more than a week at a time, my batteries will age out before this wears them out. If the application is such than you're grinding through 70-80% of capacity every day, day in and day out it would probably be a good idea to augment capacity with a 2nd string, bigger batteries (T145, L16, et al), shed loads and add generating capacity with a genset or solar. Being your own power company takes a bit of thought and engineering but the best lesson I learned from a guy I knew that lived off grid was one watt not used is two watts you don't have to make and store. You want capacity for the times you really need it, but just simple usage habits like doing all the high power stuff while the genset is running or the sun is shining minimizes the storage requirement and makes recovery time of what you have that much faster. You can design for worst case but I doubt you're keeping a heart-lung machine running in your camper. If you run out of juice and can't watch TV that night, consider it a blessing. Run a small light and read a book instead, tomorrow's another day.

I wouldn't go down the solar road unless you really, really need or want to do that. You can throw a whole lot of money and time into solar systems and it can become all consuming if you let it. I'm out camping to have fun, not dork around with obsess over complicated operation and settings. It can be terribly gratifying to source, assemble, optimize and have the system work according to plan but for my money I would rather be hiking, fishing or metabolizing beer by a campfire. If I wanted to be in a room full of glowing noise making power consuming gadgets all day I would stay home. Design the system for what you really need and go from there.

Mark B.
Albuquerque, NM

Mark_K5LXP 04-23-2020 12:12 PM

Quote:

Originally Posted by twinboat (Post 5234905)
Batteries have so many cycles in them. The deeper the cycle the less of them you get.

Right. In the interest of what that practically means though, the deeper you go in a cycle the more Ah are delivered. Factor delivered Ah along with those cycles and the impact of DOD to service life is minor. Maybe 10% difference between 50% and 80% DOD. Not enough for most people to care because their batteries will age out or be murdered before they wear out. Wearing out a set of batteries, as difficult that is to realize in practice, isn't a bad thing - you've gotten everything you paid for. Operationally it's always a good idea to keep the batteries as topped off as practical (like always keeping the gas tank above half) but just like a gas tank the bottom half of a battery works just as well as the top half. Don't be afraid to use it when you need it.

Mark B.
Albuquerque, NM

Zoomschwortz 04-25-2020 12:01 PM

Quote:

Originally Posted by Mark_K5LXP (Post 5235978)
It will, when they're really low. But it won't deliver 55A all the way until the point it switches to absorb mode. Between cables, battery terminal and internal resistance, the current will taper off as the battery voltage starts to come up. So don't count on 55A times X minutes gets you from one SOC point to another, it's not linear.



"Better" for you would be to run the genset once every 3-4 days. "Better" for the batteries is to keep them as close to 100% SOC as you can. I run the genset in the morning and the evening. If it's hot and I run the A/C in the afternoon that counts as the evening run. Point being is that you don't have to block out a regimented time to do this, just run however long you need to whenever you're there anyway. If you're over 80% I probably wouldn't bother running the genset unless I needed it for something else. I don't ascribe to the "50% rule" so will use up what I have if circumstances dictate. In the interest of "making hay while the sun shines" and not so much battery happiness it's a good idea to keep them as charged as you can just in case something comes up you need the extra run time or power.



What I think would happen is the 2nd charger would apply charge current, the terminal voltage would bump up and both chargers would switch to absorption mode. Some chargers may have a hold time before switching, some might wait for a particular current taper. Hard to say when you're talking two different chargers.

You can always turn up the absorption threshold voltage or disable it entirely, and just cram bulk amps into them until they're "full". At elevated voltages (what you'd need to have to keep higher currents flowing) a portion of that charge energy will be used to dissolve water, generate heat and damage the plates. So careful how hard you want to push it - you'll return Ah 'quicker' but the life of your batteries will be 'shorter'.



Yep.



Some better than others, ones like the Victron and Trimetric are pretty good. They crunch operating parameters on the fly and give some pretty accurate numbers. More than $100 though. I use one of the $20 amazon ones, they tell you all you need to really know for day to day operating. The statistics, history and predictive values the fancy ones offer is curious and interesting but frankly I don't care. I run the stuff I want, and charge up when I can. At the end of the day that's all batteries need to do.

During outings I don't worry too much about getting through an absorb phase and the only lower limit I watch is never go below 10.5V under load. If I was doing this for extended periods (months at a time) this would take it's toll on the batteries but for a few weeks a year and rarely more than a week at a time, my batteries will age out before this wears them out. If the application is such than you're grinding through 70-80% of capacity every day, day in and day out it would probably be a good idea to augment capacity with a 2nd string, bigger batteries (T145, L16, et al), shed loads and add generating capacity with a genset or solar. Being your own power company takes a bit of thought and engineering but the best lesson I learned from a guy I knew that lived off grid was one watt not used is two watts you don't have to make and store. You want capacity for the times you really need it, but just simple usage habits like doing all the high power stuff while the genset is running or the sun is shining minimizes the storage requirement and makes recovery time of what you have that much faster. You can design for worst case but I doubt you're keeping a heart-lung machine running in your camper. If you run out of juice and can't watch TV that night, consider it a blessing. Run a small light and read a book instead, tomorrow's another day.

I wouldn't go down the solar road unless you really, really need or want to do that. You can throw a whole lot of money and time into solar systems and it can become all consuming if you let it. I'm out camping to have fun, not dork around with obsess over complicated operation and settings. It can be terribly gratifying to source, assemble, optimize and have the system work according to plan but for my money I would rather be hiking, fishing or metabolizing beer by a campfire. If I wanted to be in a room full of glowing noise making power consuming gadgets all day I would stay home. Design the system for what you really need and go from there.

Mark B.
Albuquerque, NM


Thank you so much for this in-depth information. It looks like you and I are in the same boat.


If I could go 7-10 days without going below 50% and not needing a charge, that would be wonderful. If I was down to 50% and could at least get back to 90% charge in 4 hours without noticeably harming the batteries that would be great.
I do not and most likely will never have a TV in my trailer. I use the radio if I can get a signal. Majority of use will be lights, water pump, radio and furnace when it is cold. I may, at some time consider an inverter.


When I go camping, my main goal is camping, fishing, hiking, looking at the mountains, wildlife and birds. I don't like being tied down to the trailer for a large portion of the day unless I am sitting by a fire.



I have been checking out the suggested converter/chargers and it looks like installation will be a snap, as long as the new converter/charger is not physically to large. I am a little confused when comparing the different brands and options and in some cases their websites add to the confusion.
All I really care about for a new converter/charger is, which one will do the best job at charging my batteries in the shortest time, give the batteries a reasonable life span and easily replace the current converter/charger in my WF-8955pec

Batteries:
For a core, I have 1 mostly used up 12v Interstate that came with the trailer and around here, except for Costco's $15 core, everyone else wants $27 for core which really jumps the prices for new batteries up.


My GC2 battery choices, including core charge is the following.


US Battery AH232 $177.17 ea
Trojan T-105 AH225 $190.04 ea
Centennial AH220 $157.95 ea
Duracell AH235 $177.00 ea
Costco Interstate AH210 $114.00 ea


4 Costco's $456 + tax 410ah

6 Costco's $684 + tax 630ah

4 Centennial $631.8 + tax 440ah
4 Trojan $760.16 + tax 450ah


Are the Costco Interstate GC2 still as bad as some say?
If I had 630ah, I'm guessing that I would only cycle the batteries 20-40 times a year. If I keep up on the water and buy a high quality converter/charger, it seems like I should get at least 3-4 years out of these.


Thanks again for your input and help
Ken


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