I have Leaf EV batteries. 21k total. Will be using Magnum 4448PAE inverters (2). Trying to decide on a charge controller. Looking at charge settings I am concerned about the Classis. I don't see a bulk setting. One of the major benefits of Lithium is the ability to throw a lot of power to them. Constant voltage/amps. I plan on 4k solar so a classic 150 is adequate. Magnum PT-100 I can set to bulk and float. I only see absorb on Classis. Every absorb I know of taper amps. Magnum is proud of there PT-100 so interested in the Classis of it can do what I need. I have bms with my batteiies.
The Classic is always in the Bulk charge stage until it reaches the Absorb Setpoint and then it keeps the voltage steady until either the Absorb Time setpoint is reached or the Ending Amps ( via Whizbang ) is reached - which ever comes first. Then it goes to Float setpoint.
In Bulk it charges at all available amps though it may be limited if wanted .
Larry
So if I use a whizbang I can set ending amps at max voltage I want and it will bulk charge to that setting? Or do I even need the whizbag?
Yes you need the Whizbang because it will be able to know exactly what is going into the battery and what is going into loads. You want to base your ending amps on what is going just into the battery and not what goes into loads. The maximum voltage will be your absorb setpoint but there is also another place in settings you can set a maximum voltage just as a backup .
There are some other discussions on the forums here about using Classic with Lithium batteries. Some of it depends on what the BMS or battery manufacturer is recommending.
Go to first Forum page and do a search there for lithium .
Larry
My charging profile is fairly straight fowrd. My operating range is 40v -58v. 58v max bulk chage. Float at 57v. I can charge at max of 200 amps. Never get that from solar.
Quote from: Glenn West on August 05, 2020, 03:45:30 PM
My charging profile is fairly straight fowrd. My operating range is 40v -58v. 58v max bulk chage. Float at 57v. I can charge at max of 200 amps. Never get that from solar.
You would need to know the Absorb Voltage setpoint, Ending Amps and or Absorb Time, as well as Float voltage.
Larry
But I don't need absorb. Sounds like I need to forget the Classic.
Depending on how you set it up , it won't have much of an absorb. When I had my lithium batteries going it went right from Absorb to Float and could barely even notice it .
Larry
Looks like midnite would create a lithium profile so one would not have to set absorb. Like me trying to decide, I have never used one and really never set up one. So having a setting I can't use just seems wrong.
Quote from: Glenn West on August 07, 2020, 01:19:23 PM
Looks like midnite would create a lithium profile so one would not have to set absorb. Like me trying to decide, I have never used one and really never set up one. So having a setting I can't use just seems wrong.
It is probably best if you use a charge controller or the setpoints that your battery manufacturer recommends. That way you should have some confidence that the controller you choose and use will be the correct type for charging your batteries properly.
Larry
Person I got batterues from stated to bulk charge to 58v. Float at 57v. Disable equalize and absorb. What I read on Midnite Q&A is can't disable absorb. Can set for 3 minutes minuim. I am thinking 3 minutes is nothing really.
Quote from: Glenn West on August 08, 2020, 11:30:18 AM
Person I got batterues from stated to bulk charge to 58v. Float at 57v. Disable equalize and absorb. What I read on Midnite Q&A is can't disable absorb. Can set for 3 minutes minuim. I am thinking 3 minutes is nothing really.
Glenn, YES !! 3 minutes is nothing. From what Larry is saying, his Abosrb is so short, that it is difficult to note it on the display.
I do NOT believe that the PT-100 has any Bulk setting, at least not with the DIP switches.
What would be set, with a Bulk setting?
Bulk is called Constant Current (CC, in this case) charging, BUT, with PV as a charge source, it is very far from CC. CC charging is from the perspective of Grid chargers, where the charger has sufficient input power to charge at CC. Solar does not have that power available, for much of the Bulk, unless the battery is tiny or the PV array huge ... unless the charger waits and waits for hours until there is sufficient PV power avail to actually do CC charging. You would need a much larger PV array to do this in a Solar Day. And would gain nothing, IMO.
Some Schneider controllers that have a Boost charge voltage setting. It is NOT a Bulk setting, it just does a higher voltage stage than Absorb, starting when the Absorb voltage has been reached (IIRC), and after a time period, it is reduced to the Absorb voltage setting.
The PT-100 manual has a graph of bulk and Absorb where it has a dashed green horizontal line at 100 A, above the blue voltage line (that increases with time), but that is just the MAX 100 Amp capability of the controller. Because, with PV as the power source, nowhere that amount of current is avail from PVs at the start of a normal Bulk (where there are no clouds of fog).
Just my take on things. I know very little of Li batteries. FWIW, Vic
PT-100 does do bulk and float. Use the remote for that. I am familiar with them. But I don't need that much controller though. That thing is a beast.
Ok Glenn, Thanks,
BUT, what is being Set with that Bulk setting ? Vic
PT-100 does a cc/cv setting with remote which is constant current and volts. I may just use it anyway. I will already have the remote due to the inverters. Save me form having to buy a second remote.
OK Glenn, Thanks ...
So one can set Constant charge Voltage? This would be like a second Absorb V, guess
And if there is a Constant Current setting for the Bulk stage? Bulk is considered a Constant Current stage, but again, with PVs as the power source (NOT the Grid), that value would need to be set low to have any real effect. As with clear WX and PV having a good view of the sun, PVs are not CC sources. There is that half-Sine curve of irradiance from the sun.
It seems, that these two settings are of no practical use with PV charge sources. A CV setting would generally be just like Absorb, gotta wait and wait for that voltage to be reached, unless it was set quite low, and then not much charging would generally not have happened.
OH, and you are correct, that from the MNGP display on the Classic, the minimum Absorb time is 3 minutes. Wonder why it is not even a smaller value ...
IMO, Thanks, Vic
With my proposed solar system, at full output (how often that ever happen. lol) will be putting out 70 amps at 58v. 4k wattt solar. I have no roof top acs. All minisplit. Should charge up fairly quick at constant current. I could add 2 extra 400 watt panels as an awning, if I see a need.
OK, perhaps my statements are a bit sharp ... sorry.
Was just trying to make it clear that our solar chargers are not really CC chargers. The Classic and the PT-100 behave the same in Bulk -- producing as much current as is available at that moment, up to the Limits of the controller
One could set the PT to 100 Amps CC, but if that amount of current is not available from your PVs, the PT will only put out as much current as the PVs can produce at that moment. The Classic is exactly the same, except there is an output current Limit, that is active in any mode. And the Classic has the ability to set a Limit for the current that is actually going into the battery (with the WbJr), which would not be useful for your Li batteries.
FWIW, Vic
Thanks guys.