PD Converters and Water Usage
For Dry Campers Only No secret I've been a fan of PD converters for 15 yrs or more, and for more than one reason. The PD maintains my batteries every day of the year, except for the 4-5 months that...
Forum Discussion
The argument was about seeing the advertised 14.4v at start up. The voltage at the converter terminals won't get to that until the battery is at 14.4, no current flowing. Can't happen. Must be some voltage drop.
IMO what people are seeing is the converter voltage at almost 14.4 at start up when their batts are already at 75-80% SOC when they start the recharge.
If they started at 50% SOC, they would see converter voltage much lower at start up and it would reach 14.4 (battery less) at about 75-80% SOC depending on the charging rate
--(being the amps vs bank AH in percentage) where the higher the charging rate the sooner you hit the 14.4 at a lower SOC and amps begin to taper from there.
In my ugly graph above, you see the amps taper at about 70% SOC or earlier. That was with 100amps on four 6s at 32F. (The batts were lower than usual capacity at that low temp, so the 100amps represents a higher charging rate than usual and amps tapered sooner. At 80F, there would be a longer constant amps stage and amps would taper from about 73% SOC)
Mex likes to have no constant amps stage at all, but has such a high charging rate the voltage spikes right away to the 14.x absorption voltage he uses and he does the whole recharge as an Absorption Stage.
That has the shortest generator time, but you need a big amps charger and a big enough gen to run it.
IMO what people are seeing is the converter voltage at almost 14.4 at start up when their batts are already at 75-80% SOC when they start the recharge.
If they started at 50% SOC, they would see converter voltage much lower at start up and it would reach 14.4 (battery less) at about 75-80% SOC depending on the charging rate
--(being the amps vs bank AH in percentage) where the higher the charging rate the sooner you hit the 14.4 at a lower SOC and amps begin to taper from there.
In my ugly graph above, you see the amps taper at about 70% SOC or earlier. That was with 100amps on four 6s at 32F. (The batts were lower than usual capacity at that low temp, so the 100amps represents a higher charging rate than usual and amps tapered sooner. At 80F, there would be a longer constant amps stage and amps would taper from about 73% SOC)
Mex likes to have no constant amps stage at all, but has such a high charging rate the voltage spikes right away to the 14.x absorption voltage he uses and he does the whole recharge as an Absorption Stage.
That has the shortest generator time, but you need a big amps charger and a big enough gen to run it.
