Power Center/Converter 101

This is sort of RV electric 101 which I highly recommend for electrical newbies:

12v side of life.

2oldman wrote:
This is sort of RV electric 101 which I highly recommend for electrical newbies:

12v side of life.

I've read it a couple of times in the past. I believe it was actually bookmarked on my last laptop.

But these are more specific questions than he answers.

If you boondock a lot, you want a way to charge your battery(s) with that gen as quickly as possible. The WFCO won't stay in "bulk" charging mode very long if at all, which means you'll be running the gen all day trying to charge. The PD is a good converter, but why go with a 35? There are portable options as well. The key is to get the voltage up to about 14.8 when charging in bulk. Do some reading here on battery charging. It is a very regular topic on the tech forum!

Hi Mitch,

Don't mix your 12 volt with your 120 volt.

Your rv is 30 SHORE power. That has little to do with the converter which is 55 amps @ 12 volts DC.

The reason the current converter doesn't 'do the job well' is because modern converters are three stage. Initially they may provide high amperage to get energy back into the battery bank fast. The WFCO is a lazy bugger and never 'gets' to boost charging, so it is not preferred for generator charging.

Changing to a smaller amperage converter doesn't make a lot of sense, especially if you want to charge rapidly. If you have a 55 amp WFCO then look at a 55 amp replacement (PD or Boondocker or IOTA).

You can't go much bigger than 55 amp unless new thicker wire is installed--but probably 60 amps would work and be safe.

Since you have a SMALL generator the converter will need to have a good power factor. I know the PD 60 amp is 0.7 (not good). So it is probably not going to run on the current generator.

The Iota DLS-55/IQ4 55 amp draws 750 watts--so it probably will run on the existing generator. I don't know the power factor on the IOTA

Once you are at 85% state of charge the converter will drop down to a lower rate of charge. The maximum amps per 100 amp-hours of storage is about 12.5. At 90% state of charge that becomes even less. So folks don't attempt to recharge fully when using a generator.

If you boondock lots then it makes a lot of sense to consider a solar system. That and shore power are the only sane ways to get to 100% state of charge.

If I stay away from using my inverter, I have all the power I need to boondock. I run out of black water storage before I run out of anything else.

mitch5252 wrote:
I prefer to boondock - A LOT. I have a 2015 Fun Finder 189FDS (it's 30A). I have a Honda eu1000i generator.

Current trailer has a WFCO 8955PEC Power Center (I have no idea what the PEC means because I'm looking for the physical dimensions and can't find the PEC version.)

From what I have read in the past, this WFCO is not a very "good" converter; I do not know what "good" means - is "not efficient" a correct description? It does its job, I guess, but maybe something else would put the generator to better/more efficient use while boondocking?

Questions:

1) What, if any, would be the benefit(s) of changing the WFCO for a Progressive Dynamics converter?

2) Could my little trailer use a 35A PD converter, instead of the current 55A? I don't understand why it's a 55A converter in a 30A trailer. I'm guessing it's because CruiserRV buys them in bulk.

3) Would a 35A converter charge the battery "better/more efficiently" using the generator than does the 55A WFCO?

4) Do you think a PD would fit in current opening without major overhaul?

5) IF I made the change to a smaller amp converter, would the wires be appropriate?

I don't know if I've used all the proper terminology in this post, but maybe try to keep your replies simple, yet informative, for this electric/electronic new person...pretend you are talking to an inquisitive child. ;)

(Why, because of you all here, I learned earlier today how to disconnect the .5A hour heating thing in the seals on my new Dometic fridge! Think of all the people you guys help with patiently sharing your experience and knowledge).

There - was that a proper sucking-up? :)

I would get the upgrade kit.

What "not very good" means is that it works fine while it works..but the mean time between failures is kind of low.. Or in other words.. They die young.

So get the upgrade kit and decide if you want to install it now.. Or wait.

NOTE: the upgrade kit replaces ONLY the converter module, not the entire unit.

The 30a is the 120v amps. The 55 amp is the DC amps output of the converter which is on one of the 120v 15a circuits (which have those circuit breaker rocker switches)

The 55a WFCO will struggle at 14.4v (if it ever does that) on a 1000w gen. A 1000w gen can do about a 45a charger at most.

The WFCO bad rep is from staying at 13.6v when it should be at 14.4 to get the batteries to "gassing voltage"

As a boondocker you want the fastest recharge you can get from your gen doing a 50-90, so a replacement should be a 45a PD with Charge Wizard to ensure you get 14.4v and that the 1000w gen can run it.

Or you can leave the WFCO where it is for when on shore power and save a bunch of work. Get a different charger for fast charging off grid using the 1000w gen. A 40a VEC1093DBD if you can find one anymore, or just get the 45a PD deck mount converter with Charge Wizard and use it like a portable charger by adding your own wires to the DC output terminals with clamps on them---such as cutting a set of jumper cables in half and using a half to be your charger wires.

On question 2 you are confusing AC and DC. The camper has a 30 amp AC service, meaning you plug into a 30A outlet when you have hookups and you then have 30 amps of AC power for the air conditioning, microwave, 120v outlets, etc. The converter takes AC and converts it to DC. A 55 amp converter only draws a max of maybe 6-7 amps of 120 volt AC power.

1) The trouble with WFCO is that it rarely or never switches to boost mode. You need boost mode to charge a battery in reasonable time when using a generator. The Progressive Dynamics converter will generally go to boost mode when expected. If not there is a pendent to allow manual control. Another option is IOTA converter that starts in boost every time power is initially applied. Boost mode is about 14.4 volts and lasts about 4 hours. Normal mode is 13.6 and is very slow.


2) Yes 30 to 40 amps will work great with your RV ( and most every RV for that matter) Actually you are limited to about 40 amps rated with the Honda 1000 to prevent overload. If your 55a works now it is because it is stuck in normal mode slow charging. So with Honda 1000 the smaller converter is preferred. Even if you get an additional battery the smaller converter will do fine.


3) Yes due to the higher voltage the small PD or IOTA will charge faster (better) than the WFCO.


4) Can't say for fitment but I believe the PD9130 & PD9140 are shaped such that they will not fit in the WFCO slot. Need a PD4635 or deck mount the 9130/40 and run the wires in the back to connect. IOTA 30a should fit in the slot.


5) The wire will be just fine when going to a smaller converter.

BTW the oversize 55a is put in because it is maybe $10 extra and looks good on the brochure against the competition.

love your spirit to get in and improve this stuff.

smkettner wrote:
1) The trouble with WFCO is that it rarely or never switches to boost mode. You need boost mode to charge a battery in reasonable time when using a generator. The Progressive Dynamics converter will generally go to boost mode when expected. If not there is a pendent to allow manual control. Another option is IOTA converter that starts in boost every time power is initially applied. Boost mode is about 14.4 volts and lasts about 4 hours. Normal mode is 13.6 and is very slow.


2) Yes 30 to 40 amps will work great with your RV ( and most every RV for that matter) Actually you are limited to about 40 amps rated with the Honda 1000 to prevent overload. If your 55a works now it is because it is stuck in normal mode slow charging. So with Honda 1000 the smaller converter is preferred. Even if you get an additional battery the smaller converter will do fine.


3) Yes due to the higher voltage the small PD or IOTA will charge faster (better) than the WFCO.


4) Can't say for fitment but I believe the PD9130 & PD9140 are shaped such that they will not fit in the WFCO slot. Need a PD4635 or deck mount the 9130/40 and run the wires in the back to connect. IOTA 30a should fit in the slot.


5) The wire will be just fine when going to a smaller converter.

BTW the oversize 55a is put in because it is maybe $10 extra and looks good on the brochure against the competition.

love your spirit to get in and improve this stuff.

What smkettner said. I own a Honda Eu1000i, and I've owned a PD 9245 45 amp charge controller, with the pendant. It's limited to 14.4V. For dry camping, despite being labeled only 30 amps, the Iota DML 30 with the 14.7V cable installed is a better unit for quickly getting your batteries charged up, without overloading your Eu1000i.

If you prefer something more manual hands on, do a search for Megawatt or Meanwell in the tech section. It's also less expensive.

Your issued 12v battery (ies), you will find in the near future, are not really up to the job of providing power for dry camping needs without sulfating badly in short order. You may wish to replace with 6V GC-2 batteries wired in series for 12V when your original battery calls it quits.

One key is the small generator. Can't ask it to do more than its maximum. With smaller chargers versus time it is important that the charger not even blink as it passes a normal 14.4 absorbsion setpoint and heads up to the theroretical optimum 14.8 volt setpoint. But if it takes a long time getting to say 14.6 the total energy replaced may equal a near fully charged battery. If the generator was a 2000 watt and the charger was 75-amps the time quandary minimizes. Imagine 14.0 volts present for two full days. See what I mean?

A charger that snickers at say 14.4 volts for a limited time would be an objective worth looking for.