Parallax series 7300 converter question

[KATOOM]

I was wondering if anyone knew off the top of their head if the Parallax series 7300 convertor is a three stage unit? I have a family member with this converter and isnt sure if the trailer can remain plugged it during storage without harming the batteries. Thanks.

[KJINTF]

For the OP
If you want a Good PD 60amp converter with Charge Wizard for $120 check out this guy

http://www.rvnetwork.com/index.php?showtopic=116955

Act fast it will be gone soon

[BFL13]

I had one of those Paramodes a few years ago. The temperature compensation is based on 60F being normal and it compensates up and down from that for both its voltages.

To get the 14.2 voltage you need the optional TempAssure attachment or else it is just a single stage at 13.6 without temp comp.

I got 60 amps constant during Bulk from that 55a converter using short #4 wiring to battery.

It does have an adjustable voltage pot inside that you can twiddle, but it affects both voltages. So when I made Vabs 14.8 instead of 14.2, it also raised the 13.6 to near 14, so I could no longer use it as a float charger, just as a fast charger. ( I still had the trailer's 7355 converter to do the float and shore power job.)

The Paramode quit working for unknown reason. It was doubtful I could get warranty service after I had monkeyed with that internal voltage pot, so I tossed it and got a PowerMax (which I also monkeyed with 🙂 )

Parallax went from those initial 4400s to a 5400 line, some of which also have power factor correction (for the higher amps sizes). They are quite expensive compared with "ordinary" converters though.

[Salvo]

Those curves are just telling us the converter has an output resistance of 0.25V/55A = 4.5 mohm (the output drops about 0.25V going from no load to full load).

There's probably an inductor at the converter output that's outside the regulation loop.

In order to get the complete picture, you need to add cable resistance between converter and battery. That's usually 3 times or more higher.

So, if your cable has 15 mhom and converter 5 mohm resistance, total is 20 mohm.

If you're pulling 55A (constant current mode), voltage at battery charges to:

14.4V - 20mohm * 55A = 13.3V

Battery voltage will rise from 13.3V to 14.4V while the converter is tapering current.

[pnichols]

full_mosey wrote:
Get the automatic temperature compensating(voltage regulating per battery temperature) Parallax-Paramode-with-TempAssure and spend your time on the R in RV!

The Parllax Paramode 4455 may be a great charger for only certain batteries. Study carefully it's characteristic (somewhat poorly labeled) output curves at the link below and you'll see that it's really only a two-stage charger - with a temperature compensated boost mode and one other temperature compensated lower voltage mode. It would be perfect for my particular AGM batteries, but not so good for many others where their manufacturers recommend that a three-stage (or four stage) charger be used to maintain them.

Here's the 4455 output curves:

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

[BFL13]

full_mosey wrote:

tpi wrote:


Curious to what is the damaging effects on AGM batteries for operating at higher than recommended float voltage in higher temperatures?

Get the automatic temperature compensating(voltage regulating per battery temperature) Parallax-Paramode-with-TempAssure and spend your time on the R in RV!

HTH;
John

I thought the R was for "Repair" or between those times, "Renovate" 🙂

[MEXICOWANDERER]

When I get back to temps 32+ degrees C with my Regressive Dynamics perverter, the output is going to get shunted through a pair of TO-5 Shottky rectifiers. Maintain around 13.3 Vdc. An old 70-amp rectifier type isolator will drop voltage around .7 volts.

[full_mosey]

tpi wrote:


Curious to what is the damaging effects on AGM batteries for operating at higher than recommended float voltage in higher temperatures?

Get the automatic temperature compensating(voltage regulating per battery temperature) Parallax-Paramode-with-TempAssure and spend your time on the R in RV!

HTH;
John

[09FLSTC]

tpi wrote:
I am replacing a Parallax 7345 with a Progressive Dynamics 4645 (float 13.2V). The Parallax floated the batteries at 13.8 volts. My concern is Lifeline recommends 13.0-13.3 volts in warm to hot temperatures and I was frequently having to shut off converter or disconnect batteries-or at least I believed I had to... Example of my camping is week in Zion in summer plugged in Watchman campground.

Curious to what is the damaging effects on AGM batteries for operating at higher than recommended float voltage in higher temperatures?

None.

[tpi]

I am replacing a Parallax 7345 with a Progressive Dynamics 4645 (float 13.2V). The Parallax floated the batteries at 13.8 volts. My concern is Lifeline recommends 13.0-13.3 volts in warm to hot temperatures and I was frequently having to shut off converter or disconnect batteries-or at least I believed I had to... Example of my camping is week in Zion in summer plugged in Watchman campground.

Curious to what is the damaging effects on AGM batteries for operating at higher than recommended float voltage in higher temperatures?

[09FLSTC]

Salvo wrote:
14.4V is the threshold where gassing begins.
http://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery#Exploding_batteries

How often do those who have a PD need to add water? Perhaps once or twice a year? When on, the PD holds 14.4V for 2 hours. That's a long duration for a cell to lose few ounces of water.

RJsfishin wrote:
Quote:
Anyways, at 14.4V the battery degasses very little. It would take a long time for a battery that's initially full to drop electrolyte well below the plates.
-----------------------------------------------------------------------------
If you really believe such a thing, it would be much better if you kept it to yourself.

Its actually 4 hours. Same with Iota

[MEXICOWANDERER]

Free lithium may reduce incidents of manic depression. I hope I survive until lead is phased out of storage batteries. I had nightmares at the Shell Oil Co refinery when it was explained that one single drop of tetra-ethyl lead on the skin meant certain death. Mercury isn't that deadly

[KJINTF]

Wonder how many folks have actually seen Antimony?

Under the magnets. to the right of the VERY old IPod - getting it out of the ground leaves loads of toxic materials - wondering if LiFePo4 will be any better for the environment

[MEXICOWANDERER]

Ye gads...

No one is considering the differences that could account for the different experiences.

For the last TWENTY YEARS RV batteries have been manufactured with varying amounts of antimony. Commonly 5% to 1%. The reaction to voltages applied is like night and day.

Whew!

[time2roll]

Nothing wrong with upgrading the converter if that is what the OP prefers.



I would just get the 35 amp unless you need a fast charge running a generator.

[JiminDenver]

Well obviously when it's really hot, a few times more often than a few times a year.