Stand Alone Regulator project

[BruceM]

Brrrr, Minnesota in late January is arctic.  Best wishes and keep warm!
Bruce M

[mobile_bob]

isn't that where "international falls" is located?

if so i remember back in the 70's when it was cold here in kansas, the weather man would always tell us the overnight low in "international falls"  and it was seemingly always about 40-60 below zero (F)!

all i know is i never had much of an thought about going to that godforesaken place in the wintertime!

bob g

[thomasonw]

isn't that where "international falls" is located?

if so i remember back in the 70's when it was cold here in kansas, the weather man would always tell us the overnight low in "international falls"  and it was seemingly always about 40-60 below zero (F)!

all i know is i never had much of an thought about going to that godforesaken place in the wintertime!

bob g

Yes it is Bob, fortunately it is "up Nort".  We are a little less extreme, though it was -27f (real temp, not the Wind Chill stuff) when I arrived at the Airport in January.   Folks ask why one would come here - I can only say:  The people...  (Family in this case)


But it has given me time to work on the stand alone regulator.  Got the revised PCBs soldered up, debugged the charge pump - had  to make some adjustments.  Have been bench testing the Field driver - working great, High/Low drive, 12v..48v all automatically supported with no hardware changes needed.  And now BOTH the battery voltage sensor as well as the Amp Shunt can work with any combination of 12v to 48v systems, shunt can be high or low and the Field voltage is totally independent of the rest of the voltages. (Can use a 12v field on a 24v alternator is one wants).

I have also been playing with firming up the code.  The last few days I have been looking at all the battery manuals I can google up to fill in the default charge profile table.  Here is what I have:



A note:  All these values are 'normalized' around a 12v / 500Ah battery.  The regulator adjusts them depending on what it sees for system voltage (e.g., 48v systems - all shown volts would be 4x, and for a 1000Ah battery, all Amps would be 2x).  Of key is the way Absorption is exited:  by monitoring the Amps and measuring when the battery has reached full charge.  The max time value is there in-case something goes wrong, don't want to boil away the batteries.  It also enabled more advanced charging profiles, like # 7 as speced by US Battery for the deep-cycle batteries.  Charge profiles 1..6 are fixed and can only be changed by reloading the firmware with the Arduino environment.  (Thanks to feedback from this list, I locked those entries down)

Profile #7 & 8 can still be updated via serial ASCII commands into the serial port - either using an external USB - TLL adapter (same one used to upload new firmware), or via a computer / tablet attached via the Bluetooth.  Example, sending "$CPA:7  14.5, 200, 40"   via a terminal program would cause the Bulk/Acceptance voltage for profile #7 to be change to 14.5v, and Acceptance phase would exit after either 200 minutes or 40 Amps.

I put a copy of the battery manuals I found in the Google drive here: https://drive.google.com/folderview?id=0B5GiaoeXCQ3vMEhBZ3o1QXpYNE0&usp=sharing.  Is there a place in this list I should copy them to?  And if anyone has additional manuals, would be grateful to see them.

Thoughts welcome!   I am going to be doing another rev on the PCB, my attempt to use a soft-floor on the FET charge pump did not work.  Am also thinking if there is some interest in these, can play with the idea of changing to SMT parts and seeing about finding a short-run assembly house.  Seems like a quantity of 25 would get an assembled module complete with firmware installed (but w/o heat sink and hardware, temp probes) for under $85, or $60 is one does not want the Bluetooth modem.  Of course, being public domain, one can build up a copy by hand if they wish.  But I myself am getting really tired of soldering that darn small pitch SMT voltage sensing chip by hand...

Would anyone be interested in looking into one of these?

-al-