New PowerMax Lithium Series Converter/Chargers
- Thread starter Browneye
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What is your shore power source? How often do you have access to it?
That is a nice looking rig, one word, B-I-G,
Are you out boondocking for days at a time?
Option 1 -
Shore Power 120v > meanwell NPB-450-12
NPB-450-12 - MEAN WELL - TRC Electronics
Order MEAN WELL NPB-450-12 battery chargers on-line or call today for exceptional customer service. TRC is the USA stocking headquarters of MEAN WELL NPB-450-12 Battery Chargers. NPB-450-12 is ready to ship today.
www.trcelectronics.com
NPB-750-12 - MEAN WELL - TRC Electronics
Order MEAN WELL NPB-750-12 battery chargers on-line or call today for exceptional customer service. TRC is the USA stocking headquarters of MEAN WELL NPB-750-12 Battery Chargers. NPB-750-12 is ready to ship today.
www.trcelectronics.com
Option 2 -
Use the powermax but set cut off voltage at BMS so bms disconnects charging, but do you have a common port BMS?
Option 3
Victron charger,
I like it, $$$$ but you get fancy bluetooth etc, just cuz it does NOT have a fan does not mean that you don't have to vent it. This is the same design as Meanwell HLG line.
What is your shore power source? How often do you have access to it?
That is a nice looking rig, one word, B-I-G,
Are you out boondocking for days at a time?
Thank you. I'm looking at a few of these types of units, meanwell, aims, victron, Samlex. So far the Samlex is getting the nod. I'll check out these other ones closer.
An inverter charger would be a good option, however I've already run 4awg cable to the Xantrex, but I could put it with the lifepo pack and re-run my inverter receptacles - I have their own outlets marked for inverter power. Wiring into the 120 circuit seemed more complicated to me than I would have liked, and I would still have to decide what outlets to power up because 1000w +/- wouldn't run everything.
So...a charger.
Shorepower is a standard 30A RV plug. One AC on a 32' coach - it's a 15K btu, the largest one they make. The next size up units use two 13,500btu AC's and a 5500w generator. We have the Onan 4000w generator. So that's the other 'shorepower' source - when the generator runs. This unit is 17 years old this year and the genset has under 300 hours. It's also very quiet - you can hear it inside but we've slept with it running once or twice when it was way hot out. We won't generally stay where it's too hot to shut off AC at night. Unless we can plug in. And even then, the AC is only good for about 20-25 degree drop, so if it's 110 during the day it's gonna be 85-90 inside. We don't go to AZ in the summertime. LOL
Actually this is a smaller motorhome - but surely not a van. It has all the amenities of a larger diesel, but on a gas chassis. Newmar builds up to a 40' coach on a very similar gas chassis. And all of the diesel pushers are 34-36' and on up. My sis and BIL had a 45 footer. They also paid a half-mil for it.
We did the offroad thing for the past twenty years until the kids all grew up and moved out. I got too old to race/ride, and survived thousands of on and offroad miles without major injury or killing myself, so I gave it up. I did crack a racing helmet one time - nearly broke my neck. Not a single one of the hundreds of guys I rode with over the years escaped injury - not a single one. My son survived, and I just cringe when he tells me he wants to get a bike and ride on the road. I took up electric mountain biking - it's not nearly so dangerous, but I've already nearly cracked a rib or two, I don't know what the term 'slow down' means.
Anyway, all those years was boondocking - desert, mountains, all over western states, and never an RV park or a plug in. Imagine doing all that with a pair of golf cart batteries. That's why I thought a 230A lifepo pack would be sufficient - we've adapted to very low power usage. I got twice as much usable at half the footprint and weight, and no voltage sag. Charging is more complicated, but simpler at the same time.
I'm two years from retirement so we're getting everything lined up to be able to do more traveling, and will likely sell our place in OC - we're six miles north of Disneyland - bought the place in 1993. So you can imagine what appreciation has done - I've made more on real estate than I put in my 401K. So yeah, we mostly boondock, or prefer it. We dislike crowds, lines, noisy neighbors, bratty kids. We really hate our zero-lot line.
Wife will keep working a couple of more years after that, so she needs to be able to work on the road. We got tired of plugging those little inverters into the cigar lighter to charge laptop and phones, half the time they don't work on the laptop. So I got the Xantrex 600W Prowatt, then decided some more solar power was in order, then the lead batteries were getting old...and so the story of upgrading began. I'm a couple of grand in now.
Thanks guys, lots of good advice here. 3 months ago I had never even heard of lifepo batteries.
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Okay, update on the fixed-output charge test from last night. 12 hours later with the powermax set at 13.5 volts it is maintaining the lifepo pack. I'm not really sure why it's still putting 15W in, but the cell and total voltages have not exceeded resting level. Seems the bms keeps track of everything on the circuit - if you turn a load on it registers right away and the powermax adjusts its ouput to cover it. It's an interesting thing the way it works.
Next test will be to discharge down to 13V again and try charging with the 2-stage setting. I don't know if I can get to that tonight - it's our night out at the taproom. I make beer too, and we drink a lot of beer. LOL My prediction is that it will charge at the 14.6 for a short time, then switch to float and charge the pack the same as the fixed-output setting. We'll see.
Screen capture this morning - charger has been on since about 5pm last night. I'm a little curious why total voltage didn't reach the full 13.5 on the setting, but perhaps that's why it's still charging an amp or so. Cell voltages are 10 millivolts or so under - at least the unit isn't overcharging. The good news is the cells are well balanced. Thank you all for helping me with that. Looks like one cell is 3.372 and 13.5 setting would be 3.375 per cell. It's really close, and hasn't changed over night.
Next test will be to discharge down to 13V again and try charging with the 2-stage setting. I don't know if I can get to that tonight - it's our night out at the taproom. I make beer too, and we drink a lot of beer. LOL My prediction is that it will charge at the 14.6 for a short time, then switch to float and charge the pack the same as the fixed-output setting. We'll see.
Screen capture this morning - charger has been on since about 5pm last night. I'm a little curious why total voltage didn't reach the full 13.5 on the setting, but perhaps that's why it's still charging an amp or so. Cell voltages are 10 millivolts or so under - at least the unit isn't overcharging. The good news is the cells are well balanced. Thank you all for helping me with that. Looks like one cell is 3.372 and 13.5 setting would be 3.375 per cell. It's really close, and hasn't changed over night.
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John Frum
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@Browneye I took a closer look at that Samlex charger.
Its a weird old lead acid oriented charger.
The tail current is 3 amps which is way too low for the big blue prismatic cells.
I don't recommend it.
I think you should read these.
diysolarforum.com
diysolarforum.com
Its a weird old lead acid oriented charger.
The tail current is 3 amps which is way too low for the big blue prismatic cells.
I don't recommend it.
I think you should read these.
How charging works in the context of LFP batteries
How charging works in the context of LFP batteries
diysolarforum.com
EVE LF280N
This Datasheet corresponds to the LF280N, which is the newer model of 280 Ah cell produced by EVE. This is probably not what you have if you bought 280Ah EVE cells on the grey market (Alibaba, etc) unless you bought direct from the manufacturer...
diysolarforum.com
There is a 750w one also, this one will zap your batts faster and is ONLY $50 more
NPB-750-12 - MEAN WELL - TRC Electronics
Order MEAN WELL NPB-750-12 battery chargers on-line or call today for exceptional customer service. TRC is the USA stocking headquarters of MEAN WELL NPB-750-12 Battery Chargers. NPB-750-12 is ready to ship today.
This one looks perfect.
Price is right too - $170 That's about the same price as the Victron 25A.
EDIT: Looks like you need their SPB001 smart programmer for $61.
The samlex 30A is $220.
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Talk to me about 'tail current'. I see it referred to all the time but I just don't get it.
I take it that has nothing to do with that harsh mistress. ?
I printed out the full overkill manual, and the charging pdf you linked, and the cell stats on my LF230's and put them in a 3-ring binder. My 'battery manual'. I've read all that stuff, but it doesn't always fully register till my mind links all the loose ends. Like I say, I dropped out of electronics class in college. LOL
I take it that has nothing to do with that harsh mistress. ?
I printed out the full overkill manual, and the charging pdf you linked, and the cell stats on my LF230's and put them in a 3-ring binder. My 'battery manual'. I've read all that stuff, but it doesn't always fully register till my mind links all the loose ends. Like I say, I dropped out of electronics class in college. LOL
John Frum
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The doco I linked will explain it.
If you have questions after you have read it I will be glad to answer.
From the doc...
Gobbledygook. Configured where? Amps of what - the charger or the battery?
Evidently it's some difference between the charger and the battery that tells the charger to stop charging.
Yeah, makes zero sense to me. My eyes glaze over. LOL
Is that why the powermax never quit charging?
Gobbledygook. Configured where? Amps of what - the charger or the battery?
Evidently it's some difference between the charger and the battery that tells the charger to stop charging.
Yeah, makes zero sense to me. My eyes glaze over. LOL
Is that why the powermax never quit charging?
John Frum
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On the charger.
Not all chargers allow this to be configured.
The charge current.
When the powermax is in multi-stage mode it uses timer based charge termination.
When its in fixed voltage mode it doesn't have any charge termination logic.
In fixed voltage mode the charge current decreases as the voltage differential between the battery and the charger decreases.
Since its an asymptotic arc, the charge current approaches but never reaches 0.
Thanks for trying to comprehend the "Gobbledygook".
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Chris,
If you are going to use that 5kw genset to zap the battery, I would pick the biggest charger to zap it quickly to minimize your genset run time.
This is my rig, I am building a 300 ah 48v LFE for this. Yes, it will take up a bit of space but, I can run longer without recharge.
My recharge plan:
1. Orion type DC > DC @ 20A to 40A while the vehicle is running, as my runs are around 5 to 7 hours in Michigan and 15 hours while driving south to Pensacola, FL.
2. EV Charging station > Zap batts fast with my 3000w charger @ 50v.
With the setup you have, I would not worry of about cut-off, you are using a genset, just watch your SOC and when you are at 80% plus shut it down. you will get a feel for this, probably you will be zapped in 40 mins or so, but for this you need a TRUE 2 stage charger, which maintain CC till you reach that magic SOC.
So, if I use a genset, I want to minimize my time it is on.
If you are going to use that 5kw genset to zap the battery, I would pick the biggest charger to zap it quickly to minimize your genset run time.
This is my rig, I am building a 300 ah 48v LFE for this. Yes, it will take up a bit of space but, I can run longer without recharge.
My recharge plan:
1. Orion type DC > DC @ 20A to 40A while the vehicle is running, as my runs are around 5 to 7 hours in Michigan and 15 hours while driving south to Pensacola, FL.
2. EV Charging station > Zap batts fast with my 3000w charger @ 50v
. With the setup you have, I would not worry of about cut-off, you are using a genset, just watch your SOC and when you are at 80% plus shut it down. you will get a feel for this, probably you will be zapped in 40 mins or so, but for this you need a TRUE 2 stage charger, which maintain CC till you reach that magic SOC.
So, if I use a genset, I want to minimize my time it is on.
Attachments
Six miles north of Disneyland. ?
We haven't been to the park for over a decade. LOL They are the largest employer in Orange County. We know a lot of people that work there, a couple are neighbors.
'Zapping' is a good description. If our batteries get low for whatever reason, rainy day, charged a bunch of stuff, too much TV, charged ebikes, it's cold so the furnace runs a lot - start the generator for a quick zap. And yes, since I only need the extra juice on occasion, a fast charger makes sense. And really, that's why I got the 55A powermax - it only needs to run when I quick high amp charging. I really think fixed mode with a higher voltage setting is a good solution. I'll get 55A of charging 'till the pack comes up to a desired charge level, then shut it off. My 'automatic' charging is the solar panels, and the Orion when we drive.
Otherwise the solar panels will keep up pretty well. If we're camped out the portables are easy to deploy, and since you can actually place them in sun, at the correct angle, they'll generally produce nearly as much power as the flat-mounted panels on the roof, that are twice as big.
Looks like the MeanWell unit can be set with dip-switches - optional for custom programming with their dongle/comm unit:
We haven't been to the park for over a decade. LOL They are the largest employer in Orange County. We know a lot of people that work there, a couple are neighbors.
'Zapping' is a good description. If our batteries get low for whatever reason, rainy day, charged a bunch of stuff, too much TV, charged ebikes, it's cold so the furnace runs a lot - start the generator for a quick zap. And yes, since I only need the extra juice on occasion, a fast charger makes sense. And really, that's why I got the 55A powermax - it only needs to run when I quick high amp charging. I really think fixed mode with a higher voltage setting is a good solution. I'll get 55A of charging 'till the pack comes up to a desired charge level, then shut it off. My 'automatic' charging is the solar panels, and the Orion when we drive.
Otherwise the solar panels will keep up pretty well. If we're camped out the portables are easy to deploy, and since you can actually place them in sun, at the correct angle, they'll generally produce nearly as much power as the flat-mounted panels on the roof, that are twice as big.
Looks like the MeanWell unit can be set with dip-switches - optional for custom programming with their dongle/comm unit:
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Read thru the Mean Well NPB-750-12 manual...
2-stage charging option applies full constant current then switches to constant voltage until current reaches 10% (tail current) then shuts off.
How does it know when to switch from CC to CV?
There's an 'auto-ranging' option described but I can't make heads or tails of it. It says it's for lifepo with bms.
This unit would provide an always-on set it and forget it option. When there's 120V to the coach it fully charges the lifepo pack. Did I get this right??
Good charge rate, under 9A input draw, fully automatic.
2-stage charging option applies full constant current then switches to constant voltage until current reaches 10% (tail current) then shuts off.
How does it know when to switch from CC to CV?
There's an 'auto-ranging' option described but I can't make heads or tails of it. It says it's for lifepo with bms.
This unit would provide an always-on set it and forget it option. When there's 120V to the coach it fully charges the lifepo pack. Did I get this right??
Good charge rate, under 9A input draw, fully automatic.
How does it know when to switch from CC to CV?
Sense wires - is another concept I had to get my head wrapped around to understand the key to keeping the charging to CC longest.
Once the voltage stops rising, it switches to CV, but is the voltage of your pack the true voltage?
PowerMax in fixed volts - I like it, we have a winner here!
As a backup safety feature you could set your BMS disconnect volts to be the max you want.
Ah, Socal disney, took my oldest there 15 years back, we went to knotsberry farm also, I used to drive down your way to eat dinner from Riverside (behind mission inn)
The Mean Well charger has a sense wire for battery voltage? Or does it sense on the charge line?
The voltage pack is the true voltage at the moment - subject to settling at rest, or other service loads.
Yes, I think so too on the powermax - but I would probably set it to 14.0 to 14.4, and turn it off as soon as the charge current starts dropping, or where the cells reach the desired charge state.
On a 4 or 5 hour drive Orion should boost it up pretty well too, but it also tapers off current quite a bit as the pack gets close to the set charge voltage of 13.4. But that way I don't have to worry about overcharging on a long drive, like leaving from home when the pack is already at or near full charge.
It's a hassle to adjust the charge voltage on the powermax - disconnect the charge lead from the fuse post, turn on the charger and set it with a screwdriver and DMM, then reconnect the cable. It's under the sofa!!
We liked Knott's better than disneyland. They invented the boysenberry - they make the jam, and the Chicken Dinner restaurant is famous.
When we first moved to so-cal we put the office just up the street from there on Beach Blvd. We used to go down there for lunch on occasion.
Interestingly enough, all of the antique mining equipment at Knott's came from Calico Ghost Town, out past Barstow. That place is really wild!
It took us about 3 years to go see all the touristy stuff, now we can't be bothered. Actually kind of want to get away from this place. Starting about 2pm, the ENTIRE state of California approaches grid lock. At least everybody and his uncle is out driving somewhere.
When we leave town now a days, we getup at at 3 or 4am and get to where we're going, or out of state, by noon. We are just done with the lines for everything, and the traffic.
We came from the Seattle area, I was actually born in Vancouver BC. All our grown kids live up there now, we're looking at eastern Washington for some drier weather. The VERY BEST thing about so-Cal is the weather - about the best in the country...right behind Miami!
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John Frum
Tell me your problems
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John Frum
Tell me your problems
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Using a fet based bms for charge termination is a "bad idea"TM.
