- Limits to Battery Voltage
- Limits to Alternator Current
- Exit criteria to allow moving to next stage based on Time, Current, or perhaps battery voltage.
- Battery charastics, specifically Temperature compensation
Below is what I currently have for a 'place holder', and am open to input on the profiles as to be honest - mode are largely blank... So, is there perhaps another battery that should be added? (ala LiPro). Should one or two of the spaces be held over for 'future expansion' in the default profiles? Send me Emails (or post comments here) I would kind of like to have a 'standard' set of profiles and keep them for all revisions to the source, as I really do not want to get into a massive mixture of different source configurations in the field...
Normalized Charge profiles:
Before getting to the actual profiles, we need to understand how the regulator auto-adjusted for different battery voltages. (12, 24, 36, or 48v). To avoid making 8 profiles for each battery voltage, I decided to make all profiles 'normalized' to a representative 12v system small (500Ah) battery. Then at startup the regulator will make two adjustments to the working charge profile depending on:
- Sensed Battery voltage.
- User selected 'battery capacity size' on the DIP switches.
The sensed battery voltage is applied to target Voltages (increasing them) while the Battery Capacity Size DIP switches are used to increase target Amps.
Example - currently the 1st charge profile entry for Bulk/Absorption phase has the target VBat defined as 14.1v, and the 'exit' criteria (for exiting Absorption phase when the battery is truly fully charged) is at 10a (2% of the 500Ah battery capacity). Two examples: First a 12v large battery system then a 48v mid-sized battery:
12v 1,600Ah battery:
- Auto-sensing system voltage = 12v, multiplier is 1x.
- User selected DIP switches = On-On (1,500Ah or greater battery)
The regulator will adjust the run-time charge profiles as:
- Volts * 1x - based on sensed battery voltage
- Amps * 4x - based on user selected DIP switch
So, the 14.1v / 10A becomes --> 14.1v, 40A Meaning the regulator will drive BULK mode until the battery voltage reaches 14.1v, then switch to ACCEPT mode - holding VBat at 14.1v until the measured current drops below 40A at which time it will move to the next phase (float in the case).
48v, 800Ah battery bank
- Auto-sensing system voltage = 48v, multiplier is 4x.
- User selected DIP switches = Off-On (500Ah - 1,000Ah battery)
The regulator will adjust the run-time charge profiles as:
- Volts * 4x - based on sensed battery voltage
- Amps * 2x - based on user selected DIP switch
So, the 14.1v / 10A becomes --> 56.4v, 20A Meaning the regulator will drive BULK mode until the battery voltage reaches 56.4v, then switch to ACCEPT mode - holding VBat at 56.4v until the measured current drops below 20A at which time it will move to the next phase (float in the case).
Charge Profile States:
Each charge profile has the following basic 'stages' or modes:
- Ramping - Initial state where the alternator is brought online slowly
- Bulk - Regulator will be in Bulk mode until the battery voltage reaches the Accept voltage limit. During Bulk phase, Amps are limited by the capability of the alternator or optionally a defined max Amps.
- Acceptance - Voltage is regulated to the defined limit. Will stay in Accept until Amps drops below the defined value (indicating the battery is fully charges), or a defined time limit is exceeded.
- Float - After Acceptance, this is a 'keeper' stage where the volts are regulated to a lower setting.
Each of these stages or modes have criteria for regulation of Battery Voltage and Alternator Amps, they also have exit criteria (exiting that mode and moving on to the next one) based on time, volts and/or amps being delivered. There are also some additional stages:
- Over Charge - Between Acceptance and Float to give a final 'kick' to some battery types
- Post Float - Alternator is turned off letting the battery rest rest
- Equalize - Selected overcharging to rebalance the batteries
Charge Profiles:
Each Charge Profile (there are 8 of them, selectable via the DIP switches) has a series of entries to allow for targets and exit criteria, as defined by this structure: You might find it easier to copy and paste this structure into a text editor of your own, to better be able to read the long lines. Use a fixed-space font (e.g. Courier) to preserve tabbing and alignment.
Do I need some additional parameters? e.g., should there be a Float-to-Bulk voltage set point in addition to the Amps value?
Charge Profile Entries:
And here is the 8 entry table that I have for the current 'charge profiles': Take note that there are a LOT of blanks, for example Post Float and OverCharge are currently disabled for all entries. And the Temp Compensation is all set to the FLA type battery, which I suspect is not the right answer. So - - If you have knowledge on this area, please send me comments to: mvVikingStar@gmail.com Thanks!