time2roll wrote:
sparkydave wrote:
Strange thing is the manual cryptically says "although the converter is outputting 14.4 VDC, you will not be able to read that on a voltmeter due to the voltage-current relationship".
The best lies have a figment of truth. Yes if the charging system is producing 14.4 volts it may not be seen immediately. Charging at 14.4v & 55+ amps the voltage will rise very soon to 14.4 volts at the converter and maybe a little less direct on the battery terminals.
The WFCO trigger is to get voltage at the converter to sag down lower than 13.0 volts during the first minute of charging. This is virtually impassible without imposing a large load on the battery as stated above. If I hit my system with a 100+ amp load from the inverter for a few seconds the WFCO will go to boost mode every time.
To the OP: The 25 amp portable charger is an excellent solution and should serve you well.
the "quotes" from PD, Iota, WFCO on max current and max voltage are really misleading to say the least. The max voltage and max current spec's are independent. Max current will occur at a lower voltage when the battery is partially discharged, often I see 65A at about 13.5V The 14.4V occurs when the battery is nearing full charge and the current will usually be in the 20A or less.
In fact with both my converters running I see 100A into the battery bank and still the battery voltage is in the mid-high 13V range, a result of the battery low internal resistance when partially discharged.
Other than the WFCO the chargers WILL reach 14.4-14.6V and will reach max current on a discharged enough battery, just not simultaneously. A result of the battery characteristics and charger characteristics. During initial charging the charger is a current limited current source and during final top charging a current limited constant voltage source.