Multi-Stage Battery Charger

I am considering replacing the standard Parallax charger with a multi-stage charger.  Per PC they are happy with this charger, but I wonder about this old technology.  Have been researching the Progressive Dynamics PD9260C.  I do plan on keeping the factory installed 6V batteries until they go downhill.  I had a multi-stage on my cruising sailboat and it worked quite well.  I should note that I am having 2 solar panels installed, so wonder if this charger upgrade is necessary.

This whole thing may be moot if it does not fit in the build schedule as our unit just came in the building today.  May be a later upgrade project for me to do, but still would appreciate feedback, thoughts, experience.

Many thanks, Mike

The Samlex PWM solar charger is a multistage charger so it is safe for the batteries.

The Parallax charger, which is active when plugged in or the generator is going, to the best of my knowledge is a dumb charger and can potentially overcharge or "boil" your batteries. It also does not have an equalization mode that is needed to periodically de-sulfate your batteries to extend their life.

You would need to check with PC if they would be willing to wire in the PD9260 converter/charger into the Parallex distribution panel  in place of the Parallax converter/charger.

I would definitely ask if they would swap it out.  And right away as electrical is one of the first things they work on. 

I wish I had thought of swapping mine out for a three stage model but too late for me.  Will likely be a project for later.

It should be noted that if you use your system carefully, monitor it properly and keep the batteries watered (if needed) you might never have a problem.  "Dumb" chargers like in the Parallax load center have been used for decades with little problem.  But those chargers can, under some circumstances, boil your battery if not used properly.

My rig will have two solar panels with a PWM charger and battery monitor but the old single stage converter.  Maybe it will be fine, I'll let you know

Has anyone heard what power rating of Parallax converter/charger PC is using? or model #?

Per PC the Parallax is the 5300 Series, Model 5355, 55 amp

I would definitely ask if they would swap it out.  And right away as electrical is one of the first things they work on. 

I wish I had thought of swapping mine out for a three stage model but too late for me.  Will likely be a project for later.

It should be noted that if you use your system carefully, monitor it properly and keep the batteries watered (if needed) you might never have a problem.  "Dumb" chargers like in the Parallax load center have been used for decades with little problem.  But those chargers can, under some circumstances, boil your battery if not used properly.

My rig will have two solar panels with a PWM charger and battery monitor but the old single stage converter.  Maybe it will be fine, I'll let you know

What is the actual build time?  I think I read or was quoted 12-16 weeks (going by memory), but wondering how much is wait time and how long the actual build is.

Per PC the Parallax is the 5300 Series, Model 5355, 55 amp

Based on what I just read on an Airstream forum, that's a single stage charger. 

Quote from: sailors35 on February 22, 2017, 05:26:48 pm

Per PC the Parallax is the 5300 Series, Model 5355, 55 amp

Based on what I just read on an Airstream forum, that's a single stage charger.  

Thank you for the model info!

Looking at their online info for the model, they tell you nothing concrete about the charging provided...no charging profile and no charging voltages. Personally, I can't trust a company and product when little of its operation is disclosed when its common practice for its industry partners to do so and when its important to understand for the proper charging and life of the batteries.

Using Best Converters as a comparison the Progressive Dynamics PD4560 is only $10 more than the Parallax 5355.

I had a  Parallax converter in a previously owned camping unit which I used extensively for four years.  I also had a Victron battery monitor that allowed monitoring of battery/converter voltage, current into and out of the battery, consumed amp hours, and state of charge.  The Parallax applied 13.7 volts to the battery on a continuous basis as long as the camper was connected to shore power.

My opinion is if a person intends to camp primarily in campgrounds with electrical hookups and limits the time the unit is connected to shore power during storage the Parallax unit is an acceptable converter.  If a person intends to stay at campgrounds without electrical hookups and/or wants to leave the camper connected to power for long term storage I think the Progressive Dynamics multi stage converter is a better choice.  I had Phoenix install the PD unit during the initial build and have been very pleased with it's performance.  I moved the Victron monitor from the previous camper to the PC so we could closely monitor converter and solar panel performance.  We camp frequently in campgrounds without electricity.

My opinion is if a person intends to camp primarily in campgrounds with electrical hookups and limits the time the unit is connected to shore power during storage the Parallax unit is an acceptable converter.  If a person intends to stay at campgrounds without electrical hookups and/or wants to leave the camper connected to power for long term storage I think the Progressive Dynamics multi stage converter is a better choice.  I had Phoenix install the PD unit during the initial build and have been very pleased with it's performance.  I moved the Victron monitor from the previous camper to the PC so we could closely monitor converter and solar panel performance.  We camp frequently in campgrounds without electricity.

looking at their online info for the model, they tell you nothing concrete about the charging provided...no charging profile and no charging voltages.

If you look under the FAQ ( http://www.parallaxpower.com/faqs ) they do list the charge voltage as well as some other info.  I do not think there would be a "charging profile" as that term is used for multi-stage chargers.  Single stage ones would be constant voltage.

One thing that is not clear is whether PC installs the "TempAssure" sensor that they say adjusts the charging voltage based on the battery temperature.  I guess from reading the manual on this that it would prevent battery boil over as the voltage is dropped if the battery gets too hot.

Parallax also explains in their FAQ why they do not use multi-stage chargers.  Whether you agree with their explanation or not, at least they have addressed it.  And the TempAssure module would seem to alleviate my concerns about boiling the battery if left plugged in too long.

Having read through their FAQ my first complaint is that they still don't provide specs, they provide verbage. They provide their reasoning about how a single stage charger is just as good as a multistage but i would weigh that against that except for Parallax all of the RV battery chargers and all of the solar chargers I have seen are all multistage. (I suspect there may be some cheap single stage solar chargers out there) If they want to substantiate their position against an industry norm they need to supply supporting data through testing which they do not.

Reading through their *verbage* I would conclude (perhaps erroneously)  that their charger never goes above 13.8V. If that's true and with the TempAssure the batteries should not boil over.

At 13.8V max their chargers would also charge much slower vs chargers using an Absorption/Boost mode where batteries are quickly charged to 80% by using a voltage of around 14.4. Also, again, there is no equalization/desulfation stage which is widely stated as needed by lead acid batteries for extended life.

On the positive side, at 13.8V max/ no equalization the chargers would work well for AGMs that don't like an equalization charge which I believe are all except Lifeline AGMs.

Reading through their *verbage* I would conclude (perhaps erroneously)  that their charger never goes above 13.8V. If that's true and with the TempAssure the batteries should not boil over.

At 13.8V max their chargers would also charge much slower vs chargers using an Absorption/Boost mode where batteries are quickly charged to 80% by using a voltage of around 14.4. Also, again, there is no equalization/desulfation stage which is widely stated as needed by lead acid batteries for extended life.

That is essentially what I get from their website as well. 

I am curious how a modern 3 stage solar charger added to the rig will interact with this converter?  Will it add enough features to overcome the lack in the Parallax unit?

Quote from: jatrax on February 22, 2017, 04:33:08 pm

I would definitely ask if they would swap it out.  And right away as electrical is one of the first things they work on. 

I wish I had thought of swapping mine out for a three stage model but too late for me.  Will likely be a project for later.

It should be noted that if you use your system carefully, monitor it properly and keep the batteries watered (if needed) you might never have a problem.  "Dumb" chargers like in the Parallax load center have been used for decades with little problem.  But those chargers can, under some circumstances, boil your battery if not used properly.

My rig will have two solar panels with a PWM charger and battery monitor but the old single stage converter.  Maybe it will be fine, I'll let you know

What is the actual build time?  I think I read or was quoted 12-16 weeks (going by memory), but wondering how much is wait time and how long the actual build is.

The actual build time is about 6 DAYS based on their video.

"I am curious how a modern 3 stage solar charger added to the rig will interact with this converter?  Will it add enough features to overcome the lack in the Parallax unit?"

It would take care of the equalization if so programmed.

If the Parallax charges slower, it wouldn't be a big deal when plugged in overnicght at a campground. When needing to use the generator (i.e. boondock charging) the solar could pick up some or all of the slack would be my guess.

What is the actual build time?  I think I read or was quoted 12-16 weeks (going by memory), but wondering how much is wait time and how long the actual build is.

We ordered on November 1st.  I was informed that construction had been started on December 13th.  It was already under construction at that time.  I am scheduled to pick up on March 1st and I think the rig has been essentially done for a couple weeks.  So roughly 8 weeks from start to finish.

Now my rig had some custom work which might have stretched things.  In addition they send them out for painting which I was told can take anywhere between two and four weeks depending on the paint shop schedule.  If you have jacks installed they send it out for that as well, not sure how long that takes.  Probably depends on how backed up the shop is.

Delay from order to start of build will vary depending on how many orders they have in the book.  For me it looks like roughly six weeks at what would be the slowest time of year for them.  I talked to Leisure Travel before buying a Phoenix and they were talking six to nine months from order to delivery.