Buck Your Solar with a Mex Gizmo?
Mex has a thread about equalizing with this sort of gizmo http://www.amazon.com/DROK-Constant-Current-Converter-Regulated/dp/B00E8D7XYG There are many of these on ebay with different specs, so t...
Forum Discussion
RV daytrader wrote:
I'm guessing my controller is a fake mppt, was a $20 ebay special!! I am looking at this one now cause all the terminals are on same side, like my controller.
http://www.ebay.com/itm/DC-DC-12A-300W-Adjustable-Voltage-CC-CV-Buck-Converter-7-32V-to-0-8-28V-/131280349755?pt=LH_DefaultDomain_0&hash=item1e90eb2a3b
What is your solar panel? The 12a on the 300w gizmo would be ok for a 12v panel like a 130w with its 8.2a Isc output in full sun. But on a 230w panel, also with Isc of 8.3a output, the 12a of the gizmo would not be enough ASSuming this thing does increase the amps with a higher voltage input like a 24v panel has. That is why I wanted the 15a gizmo for my 230w panel.
On the lack of MPPT, IV curves etc. No idea! :) All I know is the (not fake) MPPT Eco-W 20amper in Float still puts out more than the 8.3 Isc of my panel when the controller has gone over to be PWM with no MPPT. (only is MPPT in Bulk, like most/all MPPTs)
So I expect during Bulk even with no MPPT that the gizmo will output more than the panel's 8.3 amps based on the high voltage input and lower voltage output, but we'll see.
EDIT- The RJ specials don't have a "boost stage" like a three-stage converter. They work just fine though. The high voltage set point is probably 14.4. They work with 12v panels. With the batteries at 12.2v, the amps will flow according to solar conditions, panel aiming etc, until the battery voltage reaches 14.4. Now the controller starts controlling and keeps the voltage from going higher till dark when voltage falls off due to lack of any more charging.
You may be blaming the controller unfairly?
