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New PowerMax Lithium Series Converter/Chargers

Browneye said:
This is my take on what the manual says as well, how I would try it first - 3 stage with float. Confirmation from Mean Well is that this charger does not re-boost without disconnecting it from shorepower. At first I was looking for a re-boost voltage level, then realize you either plug into shorepower or genset, either way it charges your battery fully then goes into float to maintain loads for the duration. And yes, it will supply loads up to the rated current output to maintain the float voltage.

Initially I thought the 2-stage was the answer, but I suspect if there's no float there's no load supply either, charging terminates at 10% of rated current, and doesn't reset until power is reset. But 3-stage for FLA at 14.2 and 13.4 seems perfect. The 'gel' setting might be good as well. As mentioned, it kind of depends on how the unit reads the battery voltage, and how much voltage sag you have in your wiring. I don't really get any sag - my 4awg leads are a foot long.

Voltage adjustment is an easy dip-switch affair, or if you really want to fine tune everything you need their BT interface and app, I think it's about $65. I captured the standard dip-switch settings from the data sheet below.

I'm anxious to hear how it works for Time2Roll.

For the WFCO unit, the only problem with the CV 13.6V is the differential is so low that current gets cut way back - it can take a long time to get there, and that is the chief complaint with them - they never boost. But yes, it's worth a shot - try it and see if it works for you. It's like just constant float.

Click to expand...
Chris, after reading about the 2 stage charging, I agree, it would just shut off when when the current drops off to 10% and I would have no power to the camper other than what is provided by the battery.......zero converter type function.

One of the things I'm failing to see (might be that thick-headed thing again), is when 3 stage charging is shown, the chart shows boost voltage at xx.x volts (depending on settings) and then the next column is float voltage. Under normal chargers, there is an absorption voltage, then float voltage. So I guess with the Meanwell, the "absorption" is when it goes out of boost and it is tapering the current down until it reaches the 10% current flow target, and then it switches to float voltage. Is that the way you see it also?
 
triplethreat said:
Chris, after reading about the 2 stage charging, I agree, it would just shut off when when the current drops off to 10% and I would have no power to the camper other than what is provided by the battery.......zero converter type function.
Click to expand...
If its terminating the charge on "current drops to 10%"...
That means that bulk/absorption are considered to be 1 stage.
Its assumed that absorption is happening for the charge current to drop.

I have a resource that explains this.
 
bagmanmike said:
I've dealing with this for the past year since I installed my Valence U27-12XP. The stock 8955 would not ever "boost" but did charge to 99% over time. More importantly (at least for my use case), it would drop to ~13.2V after 48 hours allowing the SOC to drop just below 50% during storage.

The issue came when dry camping and needing to perform a quick charge off the Honda every couple mornings if the sun wasn't cooperative.

January this year I replaced the 8955 with a 9855-LIS deck mount. It has terminals for a lithium or non-lithium configuration switch.

This box is providing 57 amps (measured by BMS and DC clamp) at 14.6V when in the LI mode and can be switched on the fly to change modes and it also seems to reset the charge cycle timing without disconnecting the battery as necessary on the 8955 - unplugging AC would not perform that task prior. Otherwise it performs the same as my old converter except I am getting much more current at 13.7V while not holding at 100% for more than a couple days.

Happy camper...
Click to expand...
Thanks for posting that info. I kind of looked at that one (9855 LIS) briefly, but I still don't like the idea of 14.6V when it is in the boost stage of charging. I also don't want to have to switch it myself to change modes, so that one is a no go for me. The closest thing I've found to what I want and what will work for me is the Meanwell NPB 750-12 and set in the 3 stage FLA mode. That would keep the boost mode at 14.2V instead of the 14.6V range, and then the float would be 13.4V AND it would stay at float voltage in order to work as a converter for 12V power to the trailer.
 
According to their data sheet, boost is CC, absorption is CV tapering off to 10% current rating, then terminate charging on 2-stage, or switch to float on 3-stage. No re-boost - charger must be power-cycled. They're calling it two stages, but as Joey says, it's really just one stage as indicated by the orange indicator led:



Here's how Mean Well explained load support:
Me: Also, will the charger in float stage or charge termination for 2-stage, support 12V loads up to the 45A capacity?
MW - Brian: yes, if there is a load beside the battery, the charge can output power to support the load. If the load is > 10% of the rate current, the charger always stays at boost charge.

Mainly I was asking about 2-stage, so in that context I take this to mean that as long as charging hasn't terminated it will support loads. But 3-stage would stay in float. I REALLY want to try this out.

The other thing I like about this charger is the <8.9A input draw. My converter-charger is now on one of the two house receptacle circuits, so 10-11A for the Powermax pretty well uses the whole thing. Fortunately it's not the kitchen/bathroom side, but still. I put it on a watt-meter and at full 55A charging it's pulling near 12A on the 120AC. It does taper off as the pack gets charged though. And for a 230A battery, 55Ah charges it pretty darn fast. Like really fast. LOL

I've about got myself sold now...I'm shopping online for them. TRC seems to be the best source. Let's see how Steven likes his. (y)
 
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smoothJoey said:
If its terminating the charge on "current drops to 10%"...
That means that bulk/absorption are considered to be 1 stage.
Its assumed that absorption is happening for the charge current to drop.

I have a resource that explains this.
Click to expand...
That makes sense to me. What doesn't make sense is that they call it three stage charging mode. Maybe they figure "3 stage" charging is easier to understand for the traditional battery charging folks? Who knows!
 
Browneye said:
According to their data sheet, boost is CC, absorption is CV tapering off to 10% current rating, then terminate charging on 2-stage, or switch to float on 3-stage. No re-boost - charger must be power-cycled. They're calling it two stages, but as Joey says, it's really just one stage as indicated by the orange indicator led:



Here's how Mean Well explained load support:
Me: Also, will the charger in float stage or charge termination for 2-stage, support 12V loads up to the 45A capacity?
MW - Brian: yes, if there is a load beside the battery, the charge can output power to support the load. If the load is > 10% of the rate current, the charger always stays at boost charge.

Mainly I was asking about 2-stage, so in that context I take this to mean that as long as charging hasn't terminated it will support loads. But 3-stage would stay in float. I REALLY want to try this out.

The other thing I like about this charger is the <8.9A input draw. My converter-charger is now on one of the two house receptacles, so 10-11A for the Powermax pretty well uses the whole thing. Fortunately it's not the kitchen/bathroom side, but still. I put it on a watt-meter and at full 55A charging it's pulling near 12A on the 120AC. It does taper off as the pack gets charged though. And for a 230A battery, 55Ah charges it pretty darn fast. Like really fast. LOL

I've about got myself sold now...I'm shopping online for them. TRC seems to be the best source. Let's see how Steven likes his. (y)
Click to expand...
As far as not entering reboost unless the power is cycled, for me, that would be everytime I disconnect from shore power and either head out to go camping, or unplug from shorepower and head home......so nothing really would affect me that i can see. And if I were boondocking, which I almost never do, there would be no shore power and I would be using up the battery until I needed to recharge it.....using a generator. At that time, it would automatically go into boost voltage level if the battery was needing to be recharged....right?

From what I am seeing about the Meanwell NPB 750-12, it looks like it would be the perfect setup for me......if the WFCO 9855 doesn't work out. I'd like to think that it will, but the more I read, the more I'm thinking that it is just not going to ever jump up into Bulk voltage charging unless I deplete the battery way down, and that will not likely be the case for my usage. Even that 12V twin compressor mod that I'm going to have done this May, and travelling for a 10 to 11 hr day will likely not deplete the battery enough to cause the WFCO to go into Bulk charging mode. And that will be my largest battery consumption user.....unless I would have to run the hydraulic leveling system from strictly the battery without shore power being plugged in.
 
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triplethreat said:
As far as not entering reboost unless the power is cycled, for me, that would be everytime I disconnect from shore power and either head out to go camping, or unplug from shorepower and head home......so nothing really would affect me that i can see. And if I were boondocking, which I almost never do, there would be no shore power and I would be using up the battery until I needed to recharge it.....using a generator. At that time, it would automatically go into boost voltage level if the battery was needing to be recharged....right?
Click to expand...
Yes. Only time to re-bulk would be if set to 2-stage while plugged in and the battery was getting low.
 
If the default settings with dipswitch doesn't get you there, surely custom programing for all parameters would.
Their 'SPB001' is $54 from digikey.com Looks like TRC doesn't sell them - not found on their site. NPB-750 not found on digikey.
Strange.


 
time2roll said:
Yes. Only time to re-bulk would be if set to 2-stage while plugged in and the battery was getting low.
Click to expand...

Browneye said:
If the default settings with dipswitch doesn't get you there, surely custom programing for all parameters would.
Their 'SPB001' is $54 from digikey.com Looks like TRC doesn't sell them - not found on their site. NPB-750 not found on digikey.
Strange.


Click to expand...
I'm pretty sure I saw them on TRC.....around $65 if I remember correctly. One of the things it looks like that is adjustable though, is the "timeout" setting for the CCT, CVT, and the FVT. I wonder if the float voltage time could be adjusted all the way up to the point that it never shut off....so that it would act as a regular converter does?
 
Yeah, found it. Odd it doesn't come up in their search:

SBP-001 - MEAN WELL - TRC Electronics

Order MEAN WELL SBP-001 power supply on-line or call today for exceptional customer service. TRC is the USA stocking headquarters of MEAN WELL SBP-001 Power Supplies. SBP-001 is ready to ship today.
www.trcelectronics.com www.trcelectronics.com

AFAIK as long as you leave the unit connected to 120VAC it stays in float mode.

BTW, they have a nifty line of inverters too. I want their 750W inverter - my cart is $475 for both. OUCH!! o_O
 
Browneye said:
Yeah, found it. Odd it doesn't come up in their search:

SBP-001 - MEAN WELL - TRC Electronics

Order MEAN WELL SBP-001 power supply on-line or call today for exceptional customer service. TRC is the USA stocking headquarters of MEAN WELL SBP-001 Power Supplies. SBP-001 is ready to ship today.
www.trcelectronics.com www.trcelectronics.com

AFAIK as long as you leave the unit connected to 120VAC it stays in float mode.

BTW, they have a nifty line of inverters too. I want their 750W inverter - my cart is $475 for both. OUCH!! o_O
Click to expand...
I haven't found a need for an inverter, but then again, I've only boondocked one time in 5 years of camping.....and that was at a track that I was at right after I bought my first trailer.....and I just ran my generator to make sure that it would do OK.
 
Browneye said:

...
Click to expand...
After looking at the charging graphs, I have gotten cold feet on this charger.

My understanding of LFP charging does not include an ABS stage, but only Bulk and Float. LFP has two stages CC and CV. CC is similar to Bulk except that when the CC Voltage set-point is reached, LFP is fully charged, whereas lead would only be 80% charged.

It is true that with a BMS, the LFP can tolerate the ABS stage, however ABS is unnecessary. Think, drop-in compatibility to replace lead.

CV is the stage where you prepare the LFP for its next use, be in cyclical or storage mode, wherein you you maintain the desired future SOC%. With lead, the goal is normally to achieve 100% SOC.

IMHO and YMMV.

Will the NPB models do CC and CV?
 
Hence the 10% tail current charge termination on 2-stage, or drop to float on 3-stage.
So, logically with lifepo4, once boost voltage is reached tail current will also be reached. I've watched this with my solar chargers.

With the programmer you can set it for either CC or CV. But even default, you get CC to setpoint, then CV to charge termination.

IMO it's a winner. So far I have yet to see a downside.

Waiting for a test and report from @time2roll
 
If possible, I would like to request a test for the NPB.

When putting the RV into storage with power available, could I choose an SOC% to be maintained by adjusting the CV?
 
smoothJoey said:
LFP batteries can benefit from some level of absorption.
diysolarforum.com

How charging works in the context of LFP batteries

How charging works in the context of LFP batteries
diysolarforum.com diysolarforum.com
They typically should not be held in cv until current approaches zero though.

CC ~= bulk
CV ~= absorption
Click to expand...

I found a graph on page 43 in my SPF 3000TL LVM-24P 3.0 manual that agrees with your pdf and the 3-stage NPB.

ChargingCurve.png

There is a formula for calculating the ABS time in Utility Charging Mode.

Time in ABS can vary between 10min and 8hrs. There is no setting for ABS time.

I can't tell if this graph applies to Solar Charging Mode. I can log into a RPi and graph later.

Does the NPB calculate ABS time?
 
time2roll said:
No time calculation. Float is triggered when current equals 10% of Bulk. If the system has significant loads this level may never be reached.
Click to expand...
I don't understand the 10% Bulk phrase.

The Growatt is my second Inverter/Charger that calculates ABS time. I believe that is a good way to do ABS. I believe that there needs to be some time limit on ABS. Otherwise the ABS Voltage could continue indefinitely. Wouldn't that be a bad thing?

If the load can be maintained at Float Voltage, why not switch? If the Float Voltage cannot carry the load, then consider re-bulk.

Is there a situation where the '10% Bulk' might continue ABS too long?
 
gelmjw said:
I don't understand the 10% Bulk phrase.

The Growatt is my second Inverter/Charger that calculates ABS time. I believe that is a good way to do ABS. I believe that there needs to be some time limit on ABS. Otherwise the ABS Voltage could continue indefinitely. Wouldn't that be a bad thing?

If the load can be maintained at Float Voltage, why not switch? If the Float Voltage cannot carry the load, then consider re-bulk.

Is there a situation where the '10% Bulk' might continue ABS too long?
Click to expand...
10% bulk means absorption until the current drops to 10% of the configured rate.
For a 50 amp charger that would be 5 amps.
The popular big blue 280ah cells have a recommended tail current of .05c(14 amps).
In reality optimal tail current will depend on both the bulk voltage, bulk current and probably cell temperature.
 
smoothJoey said:
10% bulk means absorption until the current drops to 10% of the configured rate.
For a 50 amp charger that would be 5 amps.
The popular big blue 280ah cells have a recommended tail current of .05c(14 amps).
In reality optimal tail current will depend on both the bulk voltage, bulk current and probably cell temperature.
Click to expand...
If there is a 6A parasitic draw, then ABS would continue indefinitely because charge Amps would never fall below 5A.

An ABS timer is a good thing.
 
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