Power Max replacement board

The 4400's are 3 stage converters.

Phil, it seems the 5400s are the same charging profile as the 4400s, but like those you must have the TC module added. Add dollars for that too.

Besides giving it the "boost" stage (was only 14.2 ISTR) the TC has the socket for the long temp probe wire that has the battery terminal on it with the temp sensor at the ring terminal.

The big thing is the 5400s also come with PF correction starting at the 65a level, which is lower than some others start at (eg 75a for PowerMax)

You wanted that lower portion replacement which is also out.

BFL13 wrote:
Only thing is, they are very expensive

Probably not as expensive as the latest Xantrex stuff!

I didn't take the time yet to study the new Parallax models. Do you know if their new models have three stages instead of two, and include remote temperature probes with long extension cables for battery mounting so that they can feedback to their circuits for adjustment of all three stages?

I'm guessing that - for the Xantrex units' big bucks - one gets temperature adjustment of all of their stages?

FWIW, my particular RV batteries say right on their labels to take care of them with only two stages being needed ... hence my comments about two stages being all that's needed if the two stages are compensated via temperatures right at the battery.

Phil those Paramodes that Randy still has are the prototypes for the new ones that have finally come out. I don't know what happened but Parallax sort of died for a couple years but now are finally where they meant to be back when, and have their new set of converters out.

http://www.parallaxpower.com/ESM.htm

Only thing is, they are very expensive

BFL13 wrote:
Very few brands of converters have temperature compensation. Only one but it costs you lots (Parallax Paramode) Some inverter/chargers have temp comp for the charger and also some solar charge controllers have it.

I see nothing against the Parallax Paramode unit, and that's what I would replace my Parallax fixed voltage converter with if I ever needed to so as to not spend too much $$. I seems like we can concentrate too much on three stages being required. Notice the lower voltage stage for the Paramode unit ... it gets nicely way down in voltage for safe maintaining/floating (as does it's boost stage get nicely temperature compensated downwards) when it's temperature probe is mounted on the battery and temperatures of the battery creep up into the high range:

https://bestconverter.3dcartstores.com/assets/images/Parallax/4400/4455%20Voltage%20Curves.pdf

However, here's one of the best RV chargers available if you can afford a bit more for the optimum. It not only has temperature compensation, but also power factor correction to get the best fuel usage efficiency and shortest charging times out of a generator when drycamping:

http://www.xantrex.com/power-products/battery-chargers/truecharge-2-2.aspx

Here's a product review on the above Xantrex unit:

http://www.rvdoctor.com/2011/03/product-spotlight-xantrex-truecharge2.html

Used distilled water on your battery, always. NO tap water.

A $15 PWM Charge controller off of Ebay, like this, has temp compensation. It is also programmable for float voltage. 10 amps is good for probably up to 180 watts of solar panel.

programmable PWM charge controller for bulk and float voltage.

His charge controller is pre installed, flush mount. Kind of a bummer.

OK so it is a WFCO converter and 30a GP solar controller.

WFCO should drop voltage to 13.2 after a few days of storage. Verify after five days as many fail to drop. Normal 13.6 could be a bit high for float for extended storage in 100+ temperatures. No real harm but watch the water.

GoPower will apply 14.4(wet/AGM) or 14.1(gel) volts for one hour each day before floating at 13.7 volts. This is too much and too high IMO especially for Tucson summers. Again watch the water level.

http://gpelectric.com/files/gpelectric/Docs/Manuals/Go_Power_MAN_GP-PWM-30_0.pdf

My recommendation is to upgrade the solar controller to a programmable unit with temperature compensation. Post how many watts the panel is and any plans for expansion for a controller recommendation.

I live in the desert too and I only hook mine up at night when battery temps (not air temps) get over 108F.

Hi wa8yxm,

That depends on where you live. According to environment Canada I go from -40 C to +40 C. Temperature compensation is a must do--and I personally get the job done with a solar charge controller. However, if the converter needs replacement, temperature compensation would be high on the list of needs. Especially so, as I now full time, so the solar can't do its job over a couple of weeks of standing vacant.

wa8yxm wrote:
Temp compensation may not be as important as you think

Randy has two choices of replacement using PowerMax. One is to just replace the lower portion with the 55amper or you can replace the whole power centre but that one has a 60amper in it. In any case the WFCO may be ok in your use in your RV so IMO wait and try it before tossing it already.

Your solar may be ok for maintaining the batt(s) at home even at 100F. It is only "on" half the 24hrs of course, so it may be more "gentle" on the batts even if the Float voltage is a tad high for 100F. You could wait and see on that too.