Converter replacement

[pulpwood007]

I need to replace the WFCO converter that came with my trailer. Past experience with this brand has shown me poor longevity and charging cycles that can fry a good battery.

I seldom dry camp but would like to be able to charge my group 27 deep cycle battery from my Honda EU2000i generator.

In looking at several brands of converters (Progressive Dynamics, Boondocker), the PowerMax looks like the most cost efficient. I would like to run the generator to charge the battery and operate a few lights in the trailer at the same time. My calculation shows about 16 amps AC available from the generator. I can't decide if I can safely go with the 55 or 60 watt converter and not overload the EU2000??

I do want a converter I can lock into the "boost mode" to more quickly re-charge the battery. I am not interested in solar as I do so little dry camping.

Advice appreciated.

[BFL13]

I didn't check amazon etc but this is a good deal and shipping

https://www.boatandrvaccessories.com/products/powermax-pm3-55lk-55-amp-12-volt-power-supply-with-led...

As mentioned, your battery will only accept the amps it can at that SOC and at that voltage, so yes get the 55 or even the 60 in case you get a second battery someday.

You need a flashlight and a small screwdriver to do the adjusments, and a voltmeter to watch while you twiddle the pot. You can use cut off ends of jumper cables (#8 or fatter gauge) in the terminals to make it a portable charger.

Looks like they forgot about the PF when telling you the watts---see my post above for the real draw on the gen with a 55 amper (it was with a PowerMax)

They get the 120v input right in their table at 11 amps.
11 x 120v = 1320

EDIT-- note 975 x 100/70 = 1393 which is closer to the 1380 I get.

https://powermaxconverters.com/wp-content/uploads/2019/02/PM3-Spec-Sheet.pdf

[time2roll]

Yes if you want to adjust the PM manually you are good to go. Sometimes hard to know the technical level of these requests.

[pulpwood007]

time2roll wrote:
The only trouble with PowerMax is the short absorption time. With 55+ amps the converter will hit the 14.6 volts fairly quick and then you get maybe 15 to 30 minutes at that voltage and you are only about 80% charged when the voltage drops to 13.6.

For a single battery deck mount I recommend the BD 1235CL at just 35 amps. This will get you closer to 90+% charged before the voltage drops. Or go with the PD9245 or PD9260 that will hold the boost voltage a full 4 hours.

I don't think so. PowerMax specs show a switch that can change from three stage auto to manual, locking output at 14.6. One only needs to remember to switch back to auto after fast charging of battery. I do like the remote pendant on the PD. Just wouldn't use it much for the price difference.

PM on auto:14.6 vdc for 0.5 hrs, 13.6 for 12 hrs, then to 13.2.

[time2roll]

The only trouble with PowerMax is the short absorption time. With 55+ amps the converter will hit the 14.6 volts fairly quick and then you get maybe 15 to 30 minutes at that voltage and you are only about 80% charged when the voltage drops to 13.6.

For a single battery deck mount I recommend the BD 1235CL at just 35 amps. This will get you closer to 90+% charged before the voltage drops. Or go with the PD9245 or PD9260 that will hold the boost voltage a full 4 hours.

[pulpwood007]

morley wrote:

klutchdust wrote:
Best Converter without a doubt. Plug and play, excellent customer service . Call them, tell them what you need. fixed my issues with my batteries boiling in my Class C.

Totally agree Best Converter is the way to go, very simple lower portion replacement of your WFCO. Did it myself and it works well. Randy at Best is the “Best” very helpful and will answer all of your questions if you have any. No more boiled batteries for me now also.

I've done business with Randy before. Agree, good guy. I can just save a few bucks on the same converter branded as PowerMax.

[morley]

klutchdust wrote:
Best Converter without a doubt. Plug and play, excellent customer service . Call them, tell them what you need. fixed my issues with my batteries boiling in my Class C.

Totally agree Best Converter is the way to go, very simple lower portion replacement of your WFCO. Did it myself and it works well. Randy at Best is the “Best” very helpful and will answer all of your questions if you have any. No more boiled batteries for me now also.

[pulpwood007]

BFL13 wrote:
A single 27 will accept about 45 amps at 50% SOC and taper almost right away for its Absorption Stage. If you hit it with 60 amps all that happens is the amps will immediately drop to whatever the 27 will accept and taper from there.

That's with a flooded battery--don't do that with AGM or Si02--stick with their 27% charging limits--ie 27 amps on a 100AH batt or you can use your 55 amper on a pair of 100s. LFP can take it though.

ISTR a Honda 2000 spec is 13.3 amps at 120v for running output of 1600w (VA really)

I prefer the PowerMax line (same as Boondocker, a rebadged PowerMax) but the PD with Charge Wizard might be easier to operate if you are not ready to do manual voltage adjustments to suit your battery specs. (or you can chose the standard three-stage automatic mode if on shore power) If you are on shore power it doesn't matter about which converters--they all do about the same Float voltage.

Most converters at 75 amps and below are not power-factor corrected and their PFs are about 0.7, so you have to add that to what the generator will have to supply.

EG, as measured with a Trimetric and a Kill-A-Watt here is how it works for a 55 amp converter with battery accepting 56.8 amps and rising through 13.7 volts. (3000w Honda generator)

124.7 v, 11.06 a, 980w, 0.7PF, 1380VA (Kill-A-Watt )

So the Honda 1600 VA would supply that 1380VA. Same deal with a 75 amp converter needs the gen supplying 1700 VA, so the Honda 2000 would be a little overloaded. The Honda 2200 is rated for 1800VA though, so that would be ok with a 75 amper.

My B&S P2200 just barely runs my 75 amp converter which pulls 1700VA and the gen is rated at 1700VA.

You have a choice if the WFCO does run of leaving it in place and get a deck mount converter to work with the gen, or else replace the WFCO "lower portion" with a better converter.

Thanks, good info. This will be a deck mounted (stand alone) converter, not one housed in the power distribution box.

It sounds like the 45 amp converter would be fine for my group 27 lead acid battery, and run well on the EU2000. The only catch is that the 55 amp model is the same price on Amazon.

So. I guess the question is if the single 27 accepts max 45 amps at 50% charge level, will the converter charge output drop accordingly, and hence draw less current on the AC input side? I would think definitely yes since the DC output load has decreased, and I could probably calculate that using the power factor.

Obviously I'd like to go with the 55 amp model which I know the EU2000 would supply, but also have a little power left over to run lights and maybe TV in the trailer. Looks like I need to get the AmpClamp out and do a little measuring.

As far a manual adjustments, I have no problem with that. 99.9% of the time the 3 stage auto mode will be fine. I just want to have the option of locking in boost mode for rapid battery recharge when needed. I do like the remote pendant the PD offers, but again going into the PowerMax as seldom as I would be needing boost would be no issue.

Edit: Just spoke with PowerMax and found the 55 amp converter will draw 975 watts (under full load) from the generator. Looks like I'm golden!

[pinesman]

Keep in mind that while your might not generator will not get above idle with the WFCO, putting in one of these better converters will cause your generator to speed up a little for a while, or at least that is my case with my Boondocker 55, 4 batteries and 2000w generator.

[BFL13]

A single 27 will accept about 45 amps at 50% SOC and taper almost right away for its Absorption Stage. If you hit it with 60 amps all that happens is the amps will immediately drop to whatever the 27 will accept and taper from there.

That's with a flooded battery--don't do that with AGM or Si02--stick with their 27% charging limits--ie 27 amps on a 100AH batt or you can use your 55 amper on a pair of 100s. LFP can take it though.

ISTR a Honda 2000 spec is 13.3 amps at 120v for running output of 1600w (VA really)

I prefer the PowerMax line (same as Boondocker, a rebadged PowerMax) but the PD with Charge Wizard might be easier to operate if you are not ready to do manual voltage adjustments to suit your battery specs. (or you can chose the standard three-stage automatic mode if on shore power) If you are on shore power it doesn't matter about which converters--they all do about the same Float voltage.

Most converters at 75 amps and below are not power-factor corrected and their PFs are about 0.7, so you have to add that to what the generator will have to supply.

EG, as measured with a Trimetric and a Kill-A-Watt here is how it works for a 55 amp converter with battery accepting 56.8 amps and rising through 13.7 volts. (3000w Honda generator)

124.7 v, 11.06 a, 980w, 0.7PF, 1380VA (Kill-A-Watt )

So the Honda 1600 VA would supply that 1380VA. Same deal with a 75 amp converter needs the gen supplying 1700 VA, so the Honda 2000 would be a little overloaded. The Honda 2200 is rated for 1800VA though, so that would be ok with a 75 amper.

My B&S P2200 just barely runs my 75 amp converter which pulls 1700VA and the gen is rated at 1700VA.

You have a choice if the WFCO does run of leaving it in place and get a deck mount converter to work with the gen, or else replace the WFCO "lower portion" with a better converter.

[CA_Traveler]

Specs don't necessarily reflect normal operation. Could be for fuses, heavy load startup, low AC voltage, temperature, power factor, etc.

60A*14.8V*1.2 (20% loss) = 1065W/120V = 9A or about half the gen rating.

Plus how often/long will it actually be charging at that rate?

[klutchdust]

Best Converter without a doubt. Plug and play, excellent customer service . Call them, tell them what you need. fixed my issues with my batteries boiling in my Class C.

[time2roll]

Converters often have a Power Factor of 70% meaning they need an additional 30% of apparent or available power but they don't actually consume more power.

Xantrex white paper on power factor

[2oldman]

pulpwood007 wrote:
My calculation shows about 16 amps AC available from the generator. .

The spec plate on the eu2000 should say 13.2.

[Gdetrailer]

2oldman wrote:

pulpwood007 wrote:
My calculation shows about 16 amps AC available from the generator. I can't decide if I can safely go with the 55 or 60 watt converter and not overload the EU2000??.

Perhaps a little electrical education is in order.

I think you mean 55 or 60 amp converter. And that's at 13+ volts, so it's not equivalent to 16amps at 120v. 60a x 13v = 780 watts so your 2000+ watt generator will be fine.

A few lights is virtually no load at all.

Your "assuming" the power supply is 100% "efficient" and has perfect "1" in the pf department.

No power supply is 100% efficient, typically efficiency will range upper 70% to mid 90%, and the rest is heat..

Read HERE for more information on switching power supply efficiency..

Read HERE for information on Power Factor.

Switching power supplies are not 100% efficient and most have a pretty low PF.. Both details means on some converters which do not have "active PF correction" can consume a lot more than 780W for 60A at 13V output..

A PD9160 or PD9260 (both are 60A converters) can consume as much as 1000W at 120V under full load due to having a low PF along with the typical efficiency loss.