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Old 04-02-2008, 01:28 PM   #1
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Alternatives to Factory Converter & Inverter

Hi Everyone,

I'm putting together specifications to order a new 25' Safari SE, and would appreciate any thoughts on aftermarket alternatives to factory offerings for the converter/charger and inverter/charger.

My understanding is that the factory converter/charger is a two-stage Parallax 55A, and I would plan to replace it with an aftermarket three-stage Xantrex XADC 60A, to go along with two Lifeline Group 24 AGM batteries in place of the standard factory batteries.

According to Airstream customer service the factory inverter/charger option is a modified sinewave Trace 600W. However, I would prefer a cleaner pure sinewave inverter/charger in the 700W-1,000W range for computer and electronics use.

I have not been able to find a hardwired pure sinewave inverter/charger in the 700W-1,000W range, and anything larger seems overkill. Does anybody have any suggestions?

By the way, I plan to install a Tri-Metric 2020 battery monitor in place of the factory monitor lights, especially since aftermarket solar charging will be a future addition.

Thanks very much for any ideas!
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Old 04-02-2008, 02:40 PM   #2
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Quote:
Originally Posted by shovelbum
Hi Everyone,

I'm putting together specifications to order a new 25' Safari SE, and would appreciate any thoughts on aftermarket alternatives to factory offerings for the converter/charger and inverter/charger.

My understanding is that the factory converter/charger is a two-stage Parallax 55A, and I would plan to replace it with an aftermarket three-stage Xantrex XADC 60A, to go along with two Lifeline Group 24 AGM batteries in place of the standard factory batteries.
THe factory converter charger leaves a lot to be desired. I have an Intellitpower 9960. works great and a lot cleaner DC than the WFCO.
Quote:
Originally Posted by shovelbum
According to Airstream customer service the factory inverter/charger option is a modified sinewave Trace 600W. However, I would prefer a cleaner pure sinewave inverter/charger in the 700W-1,000W range for computer and electronics use.

I have not been able to find a hardwired pure sinewave inverter/charger in the 700W-1,000W range, and anything larger seems overkill. Does anybody have any suggestions?
I have a factory installed hard wired inverter. Inverters do not charge. They suck the life out of a battery.
You can try the solar industry. They have lots of hardwired inverters.
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Old 04-02-2008, 03:37 PM   #3
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SB,

If you are going to be 'connected' most of the time in a campground, you can use an 'inverter/charger' that will keep your batteries charged with a 3-stage charging system and will also allow you to use the 12VDC battery power to run your 120VAC outlets via the inverter section of the device.

Xantrex makes the 'Prosine' series of inverter/chargers, but they start at 2000watts. They also make a 1000 watt inverter-only model, but you could couple this with any of their converter/charger models to cover your needs.

They also have a 1000 watt 'modified' sine wave inverter charger, the Freedom 458 with a 50 amp integral charger. I have seen many of these, in the larger capacities, used in large motor homes and most of the owners use TVs and lap tops with no problems. You might want to look into this as well.
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Old 04-02-2008, 04:05 PM   #4
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hi 'bum

there is a long thread about 3 stage chargers, which no doubt u've seen...

http://www.airforums.com/forums/f206...yet-17326.html

not much in it yet on the new xanterx 3 stage unit yet, even though the o.p. is now vending it.

Quote:
Originally Posted by shovelbum
... I would prefer a cleaner pure sinewave inverter/charger in the 700W-1,000W range for computer and electronics use...
no details of HOW u plan to use the inverter but...

unless you have some gadget with higher power needs,

my understanding is, using a hardwired 600 or 1000 or 2000 watt unit is wasteful/inefficient, along with the limits of one location...

2 or 3 or 4 small inverters placed where needed and matching the gadget (20-30% extra) is a more energy thrifty approach.

pure sine wave is nice but hardly essential IF the gadget (laptop or tele) has it's own converter/filter in line, again based on novice knowledge...

and IF planning to use a 1000 watt appliance the 2 group 24 batteries will be sucked down quickly...

is solar part of your plan?

is a/s willing to do the install/upgrade at the factory (on the line) or in the service center, or is the dealer gonna do it b4 delivery?

cheers
2air'
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Old 04-02-2008, 04:48 PM   #5
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OK, now I'm getting confused.

I always thought that a converter charged the battery and supplied 12V power, and an inverter converted 12V to 115V. Michelle (who has a degree in EE) suggests the same.
Lewster, who is normally spot on and whose opinion I value, refers to an "inverter/charger".
What gives???
Somebody splain it to me please.
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Old 04-02-2008, 06:17 PM   #6
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Hi Lewster,

Thanks very much for replying to my post.

Quote:
Originally Posted by lewster
Xantrex makes the 'Prosine' series of inverter/chargers, but they start at 2000watts. They also make a 1000 watt inverter-only model, but you could couple this with any of their converter/charger models to cover your needs.
Learning as I go along......

If I have a converter/charger and an inverter without a built-in charger, will the batteries still charge when the generator runs? If I understand it, the batteries do charge through the converter/charger when hooked up to shore power.

Air, I always look forward to your thoughts.

Quote:
Originally Posted by 2airishuman
no details of HOW u plan to use the inverter but...

unless you have some gadget with higher power needs,

my understanding is, using a hardwired 600 or 1000 or 2000 watt unit is wasteful/inefficient, along with the limits of one location...

2 or 3 or 4 small inverters placed where needed and matching the gadget (20-30% extra) is a more energy thrifty approach.
Again, not certain what I don't know......

I was figuring that one, hardwired inverter would take care of all AC outlets at once so that multiple devices could be plugged into the various AC outlets.

I think the Airstream 600 watt inverter is about the right size, with some margin, since you're not going to have that many watts going at once.

Quote:
Originally Posted by 2airishuman
pure sine wave is nice but hardly essential IF the gadget (laptop or tele) has it's own converter/filter in line, again based on novice knowledge...
I don't know enough about my laptop or tele to know if they have their own converter/filter in line. I was planning on running the laptop off its own battery and charging the battery from an AC outlet....maybe there's a better way? I just figured "why not plan ahead" and go with the pure sinewave version in case it was needed in the future for some new gadget or ???

Quote:
Originally Posted by 2airishuman
and IF planning to use a 1000 watt appliance the 2 group 24 batteries will be sucked down quickly...
Yeah, I know I have to use the generators (or shore power) for the microwave and air.

Quote:
Originally Posted by 2airishuman
is solar part of your plan?
Solar is definitely part of the plan but I'm going to wait awhile and do that aftermarket...thanks for your posts on the subject.

Quote:
Originally Posted by 2airishuman
is a/s willing to do the install/upgrade at the factory (on the line) or in the service center, or is the dealer gonna do it b4 delivery?
I'm figuring the dealer (to be determined) would do the install/upgrade before delivery...although I've also thought since Inland and C&G have such good reputations as Airstream specialists that they might do a cleaner/better job. Any thoughts on that one...?

Thanks,
shovelbum
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Old 04-02-2008, 06:18 PM   #7
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Inverters change power from DC to AC. Rectifiers change power from AC to DC, but the convention in RVing is to use the term "converter". See here and here.
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Old 04-02-2008, 06:35 PM   #8
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This ain't Luuuuucy....but.....

Quote:
Originally Posted by Fyrzowt
OK, now I'm getting confused.

I always thought that a converter charged the battery and supplied 12V power, and an inverter converted 12V to 115V. Michelle (who has a degree in EE) suggests the same.
Lewster, who is normally spot on and whose opinion I value, refers to an "inverter/charger".
What gives???
Somebody splain it to me please.
Dave
Here is the straight dope:

Power converters that are used in RVs take the incoming 120VAC and 'convert' it into 12VDC to charge your batteries AND provide the 12VDC for the interior items of the coach. They do nothing when you are not connected to a 120VAC source.

Inverters take 12VDC from your batteries and change or 'invert' this DC voltage into sine wave AC power. The better ones will actually create a 'pure sine wave' that very closely resembles what you get from the outlets in your house (assuming that you have one ). The cheaper ones create a 'modified' sine wave that actually looks like a combination of little square waves that 'average' out to approximate a sine wave. The real cheapies produce a wave so far from a sine wave that they can actually damage some equipment.

OK, now here's where it gets sticky............ An inverter/charger like those used in just about every large motor home that I work on, actually does BOTH operations. While connected to shore power, or while using the coach's generator, this device will charge the house batteries properly (there are multiple settings on the control panels for battery type, temperature based charge rates via sensors, and excellent 3-stage charging).

If the power goes down while connected to shore power, or while traveling down the road, the inverter section will take the 12VDC from the house batteries (if turned on) and power selected outlets in the coach with 120VAC that it produces.

Let me know if you need any more 'splainin' .
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Old 04-02-2008, 07:08 PM   #9
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Get the factory Inverter option.

Quote:
Originally Posted by thecatsandi
THe factory converter charger leaves a lot to be desired. I have an Intellitpower 9960. works great and a lot cleaner DC than the WFCO.

I have a factory installed hard wired inverter. Inverters do not charge. They suck the life out of a battery.
You can try the solar industry. They have lots of hardwired inverters.
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I forgot something.....
Get the factory inverter option. This will include much needed wiring for your inverter install. Without it your outlet options will be limited.
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Old 04-02-2008, 07:09 PM   #10
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Wow I felt like I was back in school. That was some good info. and splaining just perfect for us not knowledgable in the electrical field... SAM
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Old 04-02-2008, 07:35 PM   #11
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Unless it's a total custom job, I wasn't aware that the factory did modifications on the line with components that they don't normally install or have installed.

Some of the mods I had the factory do were simply upgrades from what they had. For example, they offered the 13.5k A/C unit with standard thermostat. I upgraded to the 15k BTU A/C with comfort control system. The had them as an option on the 25' Classic so it was from parts they had in stock and was a tested and engineer approved install since they did it many time for other units.

Are you saying Airstream is willing to install a totally different 3 way than they even have in stock?
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Old 04-02-2008, 08:05 PM   #12
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hi 'bum...

there are mixed reviews and options regarding the factory inverter option...

only a couple of outlets will be available, not every one in the trailer.

in the process of changing dc to ac inverters CONSUME some energy.

'efficiency' is the term they use for this, i think.

most inverters are about 88-92% efficient, which means they consume 8-12% of their rating/capacity.

so the larger the inverter the more juice it uses, in very general terms.

so again my suggestion is sort out EXACTLY how much of this stuff inverter stuff you plan to do...

Inverter Selection

for example, i occasionally charge a lap top battery or watch tele and play a dvd, when OFF the grid.

the laptop needs 85 watts, and the tele about 90 watts. the dvd is built into the computer.

since i'm NEVER running a gadget on the inverter that needs more than 100 watts,

i use small inverters, one is 150 watt and the other is 175 watt.

of course those are PEAK numbers and continuous is about 125 and 150 respectively.

still that's more than any gadget i plug in.

using these SMALL inverters every 12v outlet it the trailer is available, and they are located all over.

i can also use these inverters in the tow vehicle and charge the laptop or other small gadgets up there, while driving.

i think silvergate ordered the factory inverter so send him a pm about how much he likes it or uses it...

lately i think he's taken the approach outlined above, using a smaller inverter to conserve while boondocking...

the small inverter he's using is identical to one i use and it has 2 years of duty without issues.

http://www.airforums.com/forums/541220-post64.html

NOW if you plan to power bigger things (in the 500-1000 watt range) get a larger inverter and hard wired.

IF your tele and computer have those 'box' things in the power line, that's the converter/filter i'm suggesting makes PURE sine wave un necessary.

Solar Ray: DC / AC Inverters

Mastervolt - FAQ

just some things to consider. it sure is FUN to order and tweak them for personal needs...

cheers
2air'
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Old 04-02-2008, 08:09 PM   #13
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Lew, you 'splained it grate.

All kidding aside, that makes sense and thank you for the info. I'm always learning something here.
Dave
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Old 04-02-2008, 10:47 PM   #14
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Two weeks ago I installed the Xantrex XADC-60 in my 2005 28' Safari. I also installed two Trojan T-145 batteries in a modified battery box. I wrote up my procedure along with photos and you can find it at:

Parallax to Xantrex Upgrade

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Old 04-02-2008, 11:58 PM   #15
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Hi Ernie,
Quote:
Originally Posted by ernie_h
Two weeks ago I installed the Xantrex XADC-60 in my 2005 28' Safari. I also installed two Trojan T-145 batteries in a modified battery box. I wrote up my procedure along with photos and you can find it at:

Parallax to Xantrex Upgrade
Ernie
You're my hero! I was resigned to the 24s with the standard battery box....great to see that the box can be easily modified for golf cart batteries. This makes a big difference since I plan to boondock a lot. I don't have the skill to do the installation myself, but whoever does the project will have you in their Hall of Fame.
Great Article...Thanks!
shovelbum
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Hi 2air,
Like your idea about small, portable inverters...although I have a 170W AC HDTV that I'd like to mount in the bedroom...and thanks for those great inverter links.
Quote:
Originally Posted by 2airishuman
it sure is FUN to order and tweak them for personal needs...
It was fun until my head starting hurting with all of the alternatives. I picked up a copy of Harold Barre's Managing 12 Volts this evening at Camping World...maybe it'll help.

I was born in Caldwell near the Oklahoma border...Go Jayhawks!
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Old 04-03-2008, 03:23 PM   #16
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For 12 volt information, here is an interesting and informative link.
Page 2 should link at the bottom of page one IIRC.
Dave

The 12volt Side of Life (Part 1)
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Old 04-04-2008, 08:22 PM   #17
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Shovelbum, several people have explained very well the difference between the converter which also charges the battery and the inverter/charger style (not all inverters are chargers) that also charge the battery so I won't rehash that discussion however I believe there is a misconception on the factory Parallax 55A converter found in most of the current Airstreams. I spoke with the Parallax engineer when I was planning our solar power install and he made it very clear to me that the Parallax 7355 converter is only a single stage charger, nor do they believe the extra cost of a dual or three stage charger is warranted. They do have a two stage model available, Parallax 7355T, but I believe that Airstream only installs the single stage model. Check to see if the nameplate label on the converter has the T suffix. On the 7300 series the nameplate label is pasted to the inside surface of the access door.
The Parallax engineer told me that they recommend that we users push the battery disconnect switch when we have the trailers plugged into shore power for any length of time, days, weeks, months, since the charger holds the voltage at a constant 13.8 volts ( Table of Contents ). Keeping the battery connected for long periods of time under this voltage will raise its internal temperature causing water to gas off and may damage the plates. Keeping it plugged in for a couple of day or long weekend should not be a problem if the liquid level is maintained.

We have tried to follow that recommendation rather than spending $200+ to up grade the converter. We don't even have to worry about maintaining the batteries because our solar system, and I believe Airstream's, connects directly to the DC bus wired to the batteries so it maintains the charge in the batteries even if they are disconnected from the converter.

I do like the 600 watt WFCO inverter that the factory installs as an option although it was not available in 2005. One of the other posters pointed out that only a few 120 volt outlets are connected to it but I don't see that as a problem since we have several 12 volts appliances. Also, the current battery capacity can't handle the load from larger inverters without exhausting the batteries; course we may install a couple more Gel or AGMs inside but not this year.

Quote:
Originally Posted by shovelbum
Hi Everyone,

I'm putting together specifications to order a new 25' Safari SE, and would appreciate any thoughts on aftermarket alternatives to factory offerings for the converter/charger and inverter/charger.

My understanding is that the factory converter/charger is a two-stage Parallax 55A, and I would plan to replace it with an aftermarket three-stage Xantrex XADC 60A, to go along with two Lifeline Group 24 AGM batteries in place of the standard factory batteries.

According to Airstream customer service the factory inverter/charger option is a modified sinewave Trace 600W. However, I would prefer a cleaner pure sinewave inverter/charger in the 700W-1,000W range for computer and electronics use.

I have not been able to find a hardwired pure sinewave inverter/charger in the 700W-1,000W range, and anything larger seems overkill. Does anybody have any suggestions?

By the way, I plan to install a Tri-Metric 2020 battery monitor in place of the factory monitor lights, especially since aftermarket solar charging will be a future addition.

Thanks very much for any ideas!
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Old 04-04-2008, 11:14 PM   #18
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It's a shame, IMHO, that Airstream...

...doesn't spec 3-stage for all their rigs. The additional costs involved at the OEM level are very little in the overall scheme of things in an RV in this price range!

Being in the battery business and an RV'er forever, I believe modern 3-stage converter/chargers are the only way to go! Many of the new RV's I've seen lately have stickers on the panel declaring 'Three Stage Charger' upgrades as Standard.

They are relatively 'idiot proof', meaning you don't have to worry about damage to your batteries if you are hooked to shore power for extended periods...Also, these chargers perform better when the battery bank is discharged...
1. bulk charge - for quicker recharging
2. finishing charge - tapers charge rate to bring battery bank up to full complete charge.
3. float charge - maintains bank at full charge without overcharging and water loss, or damage to AGM type batteries.

I got a 3-stage conversion unit from Best Converters and now enjoy well regulated battery charging without any worrys!

When I installed a 1500 watt Inverter, I used a three postiton switch on the AC input side of the circuit...SHORE-OFF-INVERTER. This is done on some boats. I can now select SHORE for normal AC external plug in service...or...INVERTER as the AC supply, and in this manner AC is supplied to all normal outlets on the rig...

I also added ON-OFF switches for the Converter/Charger and Refer AC supply so I can turn them OFF when using the INVERTER as the AC supply (don't want the conbverter running or the refer to switch over to AC during inverter use).

I have three 140 amp hour, 12 volt batteries, and can run the microwave with this inverter...but it won't perform as well as when hooked to SHORE power or a Generator...we just use it for quick stuff when we don't want to fire up the generator...we also use it for Sat TV, etc late at night, and the inverter just loafs along, not heating up at all.
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