Author Topic: charge profile, choosing charge controller  (Read 711 times)

Vic

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Re: charge profile, choosing charge controller
« Reply #15 on: August 08, 2020, 05:13:43 PM »
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
« Last Edit: August 08, 2020, 05:17:13 PM by Vic »
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

Glenn West

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Re: charge profile, choosing charge controller
« Reply #16 on: August 08, 2020, 05:41:54 PM »
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.

Vic

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Re: charge profile, choosing charge controller
« Reply #17 on: August 08, 2020, 05:57:41 PM »
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
Off Grid - Two systems -- 4 SW+ 5548s, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 3X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  Thanks MN for Great Products/Service/Support!

Glenn West

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Re: charge profile, choosing charge controller
« Reply #18 on: August 08, 2020, 06:54:07 PM »
Thanks guys.