jrnymn7 wrote:
BFL13 wrote:
IMO the batteries are fine. You got them as good as they can get, and those SGs and resting voltages after differences are not especially significant. When the batteries really do go downhill someday it will be obvious.
It is very unclear what that particular 75 amper behaves like. I don't remember you saying it ever did 75 amps even for the famous 15 minutes before or after the mod.
I see Randy has his adjustable voltage version 75 amper up now. The owner's manual should be interesting. Maybe Randy can say what happens to the regular 4B 75's stages when you do the mod like why that 15 min is still there, etc. No problem with the PM3 so why is there with the PM4 mod?
As for the pm4b, indeed, it has never gone above 46 amps output, pre or post mod, so I was becoming more and more convinced it was a 45 amp unit labeled as a 75 amper. I figured one way to figure this out was to check its input current, (Erinn had told me it should be about 9 amps), and I was getting impatient waiting for my new clamp-on AMP meter to arrive, so I powered up the pm off the near full bank, through the inverter, and hit the not so charged bank for about 20 seconds with the pm set to warp speed (full voltage). The pm came on in what I like to call "Boobs Mode" (neither boost nor abs) and volts began to rise to the lower 'abs' setting, which is the usual for the pm on discharged batts ... Hey, maybe that's what the B in pm4b should stand for??? ;) ... The Trimetric showed the amp draw quickly rise to the -90 amp range; so about 9 amps at 120v, like erinn said. Just for amusement, I switched things up and hit the near full bank the same way, and of course the voltage shot way up, real quick, and set off the low voltage alarm on the inverter; and the amp draw quickly rose to about -90 amps as before.
So just as I was becoming convinced I was dealing with a 45 amper, it appears it is a 75 amper. So now I have to consider the possibility there is an internal problem with the pm, and something is keeping it from putting out its rated amperage.....
IMO Errin was mixed up on that 120v draw, as you noted before on the actual specs it should be 12a.
http://powermaxconverters.com/pm412volt.htmlI get about 90a draw by an inverter running a 1000w kettle or toaster.
If the unit is drawing about 1000w if fits the watts spec. But those watts spec figures are suspect IMO. Eg the 1440 for the 100amper is way different from the previous spec of 1600 something , which made more sense. Also divide the watts by the 108 voltage and you don't get the amps listed either.
Another clue as to converter amps size is the set of reverse polarity fuses on it. EG a typical 55amper would have two 30a DC fuses. My 100amper PM3 has four 40a fuses. So I think a 75amper would have something in between.
Another possible clue is the size of the thermistor. The bigger converters have more of a thermistor. It is that black disc on two legs just in from where the 120v cord goes onto the circuit board near the 120a glass fuse. What is written on that thermistor?
