Should I Change My WFCO Converter?
Opinions have often been expressed, both on this and other RV forums, that most stock RV converters are inadequate to properly charge and maintain batteries and are often of poor quality. It is frequ...
Forum Discussion
The PMBC with the adjustable option and the BPCM are "manual" in that you set a voltage with the knob and it stays at that voltage until you change it.
It is also "manual" in that the unit stays on until it is unplugged/switched off unlike "automatic" chargers that shut themselves off when they think the battery is charged up (usually at about 97% SOC, so not really "full") So it can act as your converter if you like because it stays on.
So the procedure with low batts is to set say, 14.8v, and the battery voltage climbs to 14.8v (Bulk stage) while amps are constant at the rated amps (55 or 60, 75, 100, 120 whatever you bought)
Then it does Absorption stage at 14.8v while amps taper for as long as you like. While camping on generator that might be to 90% SOC. (That is when your amps are down to about 5 amps per 110AH of battery bank if you have an ammeter, so at 10 amps on a pair of 6s or 27s)
Now comes the manual part--you have to shut off the PMBC. If you leave it on till the batteries are near full at 97% then now you can
A. dial down the voltage to 13.6 and leave the unit on as your converter, or
B. turn the unit off and let your actual converter do the 13.6 on shore power.
If you ever want to Equalize at 15.5v, operate the rig on its own converter at 13.6v, disconnect the battery bank from the rig's 12v systems (take wire off battery or use the "battery disconnect switch" if any) , and now use the PMBC on the batteries at 15.5v. Amps will start at about 4 amps on a pair of 6s and taper during the time you do the equalization. Equalization ends when the SG stops rising per hydrometer. Shut off PMBC and reconnect battery bank to rig.
Out of the several options mentioned IMO pick the BPCM size you like from Randy. 15.5 is what your batts want for equalization so you don't need the 16.5 of the PM version. Randy offers a three-year warranty instead of two years. You get excellent tech support if needed. You know exactly what specifications your unit will have. It costs more than the boatandrv older version but the PM newer version would be the same or more than Randy's.
I would get the 75 instead of the 60. Repeat--the pair of 6s or pair of 27s can take 75 amps Bulk no sweat and no harm, and if your gen can run the 60, it should be able to run the 75 with its PFC. 15 more amps for $10. And if you ever went to four 6s you would really want that extra 15a.
You won't get any more amps by running the WFCO and BPCM together with the WFCO at 13.6v. If you got the WFCO to run at 14.4, then they would add their amps for most of the Bulk stage.
It is also "manual" in that the unit stays on until it is unplugged/switched off unlike "automatic" chargers that shut themselves off when they think the battery is charged up (usually at about 97% SOC, so not really "full") So it can act as your converter if you like because it stays on.
So the procedure with low batts is to set say, 14.8v, and the battery voltage climbs to 14.8v (Bulk stage) while amps are constant at the rated amps (55 or 60, 75, 100, 120 whatever you bought)
Then it does Absorption stage at 14.8v while amps taper for as long as you like. While camping on generator that might be to 90% SOC. (That is when your amps are down to about 5 amps per 110AH of battery bank if you have an ammeter, so at 10 amps on a pair of 6s or 27s)
Now comes the manual part--you have to shut off the PMBC. If you leave it on till the batteries are near full at 97% then now you can
A. dial down the voltage to 13.6 and leave the unit on as your converter, or
B. turn the unit off and let your actual converter do the 13.6 on shore power.
If you ever want to Equalize at 15.5v, operate the rig on its own converter at 13.6v, disconnect the battery bank from the rig's 12v systems (take wire off battery or use the "battery disconnect switch" if any) , and now use the PMBC on the batteries at 15.5v. Amps will start at about 4 amps on a pair of 6s and taper during the time you do the equalization. Equalization ends when the SG stops rising per hydrometer. Shut off PMBC and reconnect battery bank to rig.
Out of the several options mentioned IMO pick the BPCM size you like from Randy. 15.5 is what your batts want for equalization so you don't need the 16.5 of the PM version. Randy offers a three-year warranty instead of two years. You get excellent tech support if needed. You know exactly what specifications your unit will have. It costs more than the boatandrv older version but the PM newer version would be the same or more than Randy's.
I would get the 75 instead of the 60. Repeat--the pair of 6s or pair of 27s can take 75 amps Bulk no sweat and no harm, and if your gen can run the 60, it should be able to run the 75 with its PFC. 15 more amps for $10. And if you ever went to four 6s you would really want that extra 15a.
You won't get any more amps by running the WFCO and BPCM together with the WFCO at 13.6v. If you got the WFCO to run at 14.4, then they would add their amps for most of the Bulk stage.
