setting charging output limits

[kauaisolarman]

very interested to see if this can work

the white paper does say if you want to limit more than 2 CC each needs its own WBjr.

Im assuming they are reffering to charging 1 battery bank with both controllers

please keep me updated on the progress of this.

dont want to run the wires and conduit if it's not possible to do with 2 CC and 1 battery bank

[kauaisolarman]

any updates on this?  is it really necessary for 2 WbJr for limiting 2 controllers?

Would this be a correct assumption if using Global current limit setting for 2 controllers?

if the master controller (connected to WbJr) has the global current limit set to lets say 48A and the second controller is already putting in 30A  wouldnt the master controller sense the 30A already flowing through WbJr and only provide the remaining 18A to produce the desired maximum current flow setting of 45A max to the battery bank through WbJr?

my  reason for question is I am setting up my 48V Aquion Battery bank and need to limit the battery bank to 48A max charging input (aquion doesn't like high charge current). I plan on running Hybrid wind/solar with 2 controllers and need to make sure i can control the current flow into the battery bank when both controllers are producing power.

Max power i want to put into the battery bank is 2300 watts (48A).  I plan on running a 1500W turbine at maximum so just need to limit the power coming in from the PV CC, because,  even in maximum wind the controller with the wind power will never put enough power to my battery bank to overcharge so no need to limit the CC with the wind connected.   

[dgd]

...
if the master controller (connected to WbJr) has the global current limit set to lets say 48A and the second controller is already putting in 30A  wouldnt the master controller sense the 30A already flowing through WbJr and only provide the remaining 18A to produce the desired maximum current flow setting of 45A max to the battery bank through WbJr?

The answer to this is still No.
There has not been any new Classic firmware updates to provide this multi-Classic current limiting and AFAIK it not considered something that is a planned update in the near future.

The only method to achieve what you want is to learn how to use a micro controller, program it to read modbus registers from your Classics, then set the current limit registers on the Classics  to dynamically adjust current from each to stay within the max charge limit you require.
ie, its your controller that manages the current balancing between the two Classics

Max power i want to put into the battery bank is 2300 watts (48A).  I plan on running a 1500W turbine at maximum so just need to limit the power coming in from the PV CC, because,  even in maximum wind the controller with the wind power will never put enough power to my battery bank to overcharge so no need to limit the CC with the wind connected.

If you only want 48A charge current then I'd suggest just using one Classic with sufficient PVs to supply about 60A. This means in poor weather you may get charge currents approaching the 48A but in good weather the Classic will current limit

Dgd

[kauaisolarman]

[/quote]

If you only want 48A charge current then I'd suggest just using one Classic with sufficient PVs to supply about 60A. This means in poor weather you may get charge currents approaching the 48A but in good weather the Classic will current limit

Dgd
[/quote]

thanks dgd.  i do have a fairly oversized PV (3800W = 60-70A under varying charge voltages) for that exact purpose, but i do have an extra controller and nights here are fairly windy here so i wanted something that could give my batteries charge during the night time.

just though that the reason for global current limit was to be able to regulate charging current through the WbJr. vs the classic shunt which  would allow for use of loads while still allowing maximum charge current to the battery. 

for example; if you're using regular CC output limits and your battery has a maximum charging current of 40A and you set the CC output limit to 40A the most the CC will output is 40A, which is great until you put a load on your system and now the CC is limiting output to 40A but your battery may be only taking in 30A if you have a 10A load running. 
Whereas with GLOBAL current limit the CC limits Amperage output depending on loads/readings off the WbJr. , so, if you have a 10A load through WbJr it will be sensed and the CC will send 50A total to cover the 10A load and the maximum 40A limit that you set.

why wouldn't this work in the opposite direction?

i figured that because the current from the "wind" CC was also flowing through WbJr., the main CC with GLOBAL current limit would sense the current flowing through WbJr., and adjust its ouputs accordingly.

can you explain why this doesn't apply?

Thanks for the response

[dgd]

KS,

If the maximum current that can be provided by the second Classic is always less than the charge current max setting specified for the first Classic (with wBjr) then the current limiting logic in the first Classic will ensure the max current is never exceeded.

However, if the second Classic can exceed this max charge current setting then the first Classic can only reduce its output to zero but the second Classic keeps charging .
You could set the max output limit of the second Classic to 48A. You do not need a WBjr on the second Classic

If the turbine is small enough then you probably won't need a second Classic with Clipper. The turbine DC output could be direct connected to the DC distribution box/Epanel

Dgd

[kauaisolarman]

thanks for the input.

now i gotta learn about wind power.......

definitely going to add it on somewhere.