UPDATE --- Converter/charger issue?

You are in business! :)

Note that if you screw up the drill and twiddle the voltage pot while the left switch is in "stages" mode, it will mess up all the voltages in that mode. You can put it back the way it was as explained in the manual. (BTDT)

The adjustment is NOT to the final stage of the "stages" mode. First switch A to the right for single voltage mode, then twiddle the pot to whatever voltage. It will stay there until you change it.

For off-grid generator charging, that is all you need for a 50-90. Set 14.8v say. (14.8 at 25C is 15.2 at 5C so you want a table of temp comp voltages if you are keen)

You only want the "stages" mode when on shore power. In that mode, it does Bulk for half an hour then goes to Normal. Half an hour is not enough for a 50-90 at 14.8, which is why to use the single voltage mode for that.

Also for AGMs that require the 14.x all the way to full charge, you don't want it to drop the voltage until you say, so you use the single voltage mode for that, even on shore power.

BFL13 wrote:

ib516 wrote:
PM4 with the holes for adjustment and the LED.

I would not be sure until you open the package. The dealers/sellers often use a photo of one kind when selling another kind. Fingers crossed!

The PowerMax website link I posted earlier for the PM3-LK has the operating manual for using those two holes that would also apply to the PM4 with that feature. It does not say about the flashlight and small screwdriver you need though.

It arrived today. PM4-55. LED and two holes (A switch and B potentiometer) for adjusting the voltage at the final stage.

ib516 wrote:
PM4 with the holes for adjustment and the LED.

I would not be sure until you open the package. The dealers/sellers often use a photo of one kind when selling another kind. Fingers crossed!

The PowerMax website link I posted earlier for the PM3-LK has the operating manual for using those two holes that would also apply to the PM4 with that feature. It does not say about the flashlight and small screwdriver you need though.

PM4 with the holes for adjustment and the LED.

What exact model did you get? The LK in the name is the one with the adjustable voltage. There are still some older versions for sale with just PM3 or 4 in the name that are not so good. If it is not an LK, change that order or you will be unhappy.

LKs are no more expensive though.

It does seem there are newer "PM4" without the LK in the name but do have the two holes in the side, the internal fan, and a little green LED to show it is on.

If the one you get has the external fan and no holes in the side once you actually see it, it is not what you want.

I bought a Powermax 55 Amp 4 stage from Amazon to replace the Iota 45 Amp with IQ4 dongle. Believe it or not, the 55 Amp unit was $30 LESS than their 45 Amp one. I didn't wan to go with the 75 or 100 Amp (even though my two 6V golf cart batteries can likely take the current) because my RV wiring from the rear mounted converter/charger to the front mounted battery bank isn't very heavy gauge wire. I suspect it was spec'd by the engineers at Jayco to carry 45 Amps max on a single 12V battery so I might already be pushing it with a 55 Amp unit.

I use a Firman 3300w/3000w inverter generator for the dry camping we do. 90% of the time we have zero hook ups when camping in the Canadian Rockies.

I have a 100amp and 75 amp PowerMax. According to my Kill-A-Watt, the 100 amper pulls 1910VA when set to 14.8v and doing 103 amps.

Of course you actually use battery voltage at the time to measure your output watts, so peak input is just before DC amps start to taper down from 103 when the battery just reaches 14.x volts. (there is voltage drop at 103 amps, so battery voltage is not yet 14.8--more like 14.3 with my wiring zoo). You see the 14.8 at the end when amps are way down.

Gets sort of complicated what the max input would ever be. Anyway too much for a "2000w" inverter/gen, but ok for a "3000w" inverter gen. Don't know about in-between those size gens, such as a "2400w".

I can just run the 75 amper on my B&S P2200 at its 1700VA doing 75 amps, set to 14.8v. The gen is way maxed out but does not quit. Right on the edge.

I use #4 from the converter to battery. I think #6 would not quite do it and get full amps.

BFL thanks to your reviews I looked at the Powermax and they seem to be the least offensive converter, especially the 80 and 100 amp models if a big enough generator is used to push them. I may end up getting one and sticking a big *** handle on top and six gauge jumper cables. The Megawatts are OK but limited to 40 amps.

I like these a lot, but you have to learn how to use them and have the right "attitude" for doing things that way. See the manual for operating instructions. (It is not rocket science)

https://powermaxconverters.com/product/pm3-12v-series/

If you are not that way inclined, there are others, which do less for more money. :)

Clouseau level pep-out lighter, aptitude