Community Forums

papazulu · 03-18-2013, 10:19 AM

We are considering making the investment to upgrade to 4,000 watt inverters and are wondering if anyone else has done so, and if so, are you happy with the results and would you do it again.

The coach is all electric and we currently have the Prosine inverters which I recently learned are unavailable for replacement and unable to be repaired as other brands are. The Prosines are operating normally now, this is just a pre-emptive decision that I am considering so the inverter replacement will be on my terms at my location - rather than in the middle of a trip.

Our extended warranty company, ACC Warranty, is willing to pay me $500 each for the used take-outs but I may be able to get more for them on Ebay so that will help offset some the of the expenses.

So - if any of you have considered this, or completed this type of project, I would be happy to hear about it.

Thanx!!

michelb · 03-18-2013, 11:49 AM

I'm guessing you're looking at probably a good $2k out of pocket to do the swap so I'd be tempted to keep the Prosine until they fail. Some do fail (we have a dead one) but they don't all fail or at least, they don't all fail right away, so it could be years until you need to replace them.

As far as selling the used ones on eBay, I don't think if you'll get that much more to make worth the hassle. You might get $600 or $700 each on eBay but I don't think you'll get much more and there are fees that will chew up some of your profit (between eBay and PayPal, you're probably going to lose close to 10%).

You do get some money back selling working ones now on eBay vs dead ones later but it's certainly not enough to make up for the swap (broken ones are probably worth $200-300 on eBay, I think used ones might be worth $600-$700)

BFlinn181 · 03-18-2013, 01:11 PM

I'm curious, what would you run that requires 4k capacity? Seems to me you'll have far more potential than actual battery power. Draining the batteries at that rate will shorten their lives, I'd rather use the generator. If you have enough inverter to run the microwave, (about the biggest draw you'd use for a short time without generator) what else do you need?

papazulu · 03-18-2013, 01:19 PM

Hi,

Probably more like $6 with the batteries....

Thanks!

papazulu · 03-18-2013, 01:40 PM

Hi Bob,

Thanks for the questions. We currently have two 2kw's using 4 8D house batteries and 600 watts of solar panel. I am thinking of going to the two 4kw's and adding 4 more 8D lifelines for a total of eight 8D lifelines for a little over 2000 amp hours of capacity.

This will allow us to run roof 2 of the A/C's going down the road without running the generator - that is my primary goal. Also, we will be able to run the 1 A/C unit off of the inverters with no shore or generator for about 4-5 hours before the auto-gen start would come on. That's about all the longer I sleep anyway these days.

I have talked with several people who have lost one of their Prosine's at the most inconvenient time possible. They are not available any longer and are unable to be serviced so you must replace both inverters and remotes at that time - wherever they decide to fail.

I think it prudent to do this on my terms when I can plan to be out of the coach for a few days and have the replacements there waiting.

Thanks!!

BFlinn181 · 03-18-2013, 02:03 PM

I think if you do the math, trying to keep two 12 -15 amp A/Cs running on batteries as you go down the road will not work out mathematically, even with the engine alternator and 600 watts of solar inputting at the same time.

papazulu · 03-18-2013, 02:21 PM

Hi,

Thanks. We do have a 300 Amp Alternator pushing it...

jdr159 · 03-18-2013, 03:33 PM

Where/how are you planning on adding 4 more batteries? A lot of weight and room, and a bunch more cabling and connections to deal with.

TQ60 · 03-18-2013, 03:42 PM

Benefit there tried to do that...failed...

Some coaches as well as a few big rigs have inverter powered ac units.

Country Coach has a few.

We tried this last summer to see if it would work.

We had access to 160 amp hour AGM batteries that we could add, the altermator is 160 amp so DC power not an issue.

We picked up a 2000 watt inverter that had 4000 watt surge, the start current was more than it could handle, the inverter was connected directly to a pair of new 1500 CCA 8D batteries.

Much homework later, unless the AC is designed for the inverter with special start kits, or you have a very large inverter 5 K minimim you are going to have problems, even if it works it could cause damage to the compressor.

Two options.
One, just run the genny down the road, the fuel consumed is modest.

Assume traveling 60 MPH and genny using one gallon per hour ( both action running) and assume you get 10 MPG.

(using above for easy math )

In one hour you use 6 gal fuel without genny.

60 miles / 10 MPG is 6 gallons

Add one more gallon for the genny and the mileage is 60 / 7, or about 8.5 MPG.

Option 2 would be to install system designed for inverter operation, huge investment plus nothing is free.

You could charge batteries with utility power, but driving will have the alternator charging batteries thus pulling power from your engine.

Will it be close to the 1.5 MPG of the generator?

Who knows, but you will wear out many generators before you are even close to return on investment.

Besides, you need to exercise the genny anyway, if done while driving it is free, you would be doing it anyway...

Cat320 · 03-18-2013, 04:44 PM

papazulu...okay, so what is the origin of your screen name? As an old Army helicopter pilot I've been into my share of "papazulus'' some friendly, some not so friendly...but the guys on the ground were always glad to see us. I know, I was on the ground my first tour.

papazulu · 03-18-2013, 09:32 PM

Cat320: Ha, good call! Yep, you are always glad to see Snoopy on the way!

papazulu · 03-18-2013, 09:52 PM

TQ60: Thanks for the info.

We get 5.0 mpg towing and 5.75 mpg not towing - normal highway driving. 3.5 mpg to 4.5 mpg in mountain grades but that is first up the hill. Gen burns 1.25 gal an hr. So, with the gen running we are real close to $1.00 a mile... I am interested in the noise reduction while running down the road as well as saving $75+ per day in gen. diesel consumption.

I have talked more with my representative at ACC warranty and they are now willing to add the upgraded electrical system to my service policy coverage with them in exchange for my take-out Prosines. They indicated that the increased components cost would outweight the almost certain Prosine replacement claims to come for them.

Back to the power consumption issue; I am not sure I fully understand why two 4000 watt inverters powered by 8 8d's and a 300 amp alternator will not run 2 roof airs however. I had an 8kw onan in another coach and that would run two airs and everything else in the coach at the same time.

I am not an electrician or an engineer and was hoping to maybe hear from one or both.

Thanks again.

BFlinn181 · 03-18-2013, 10:29 PM

This page contains a calculator you can plug in values and see what your inverter and batteries can handle:
Inverter FAQ - DonRowe.com - Frequently Asked Questions about Power Inverters

Here's more info: http://answers.yahoo.com/question/in...8042806AAUWRm2

FlyingDiver · 03-18-2013, 10:43 PM

You don't say what generator you have, but 1.25g/hr sounds very high. Average draw for the roof ACs will be 30-40 amps total, I would think. That's less than 1/2 load for a 8kW unit, and the Onan chart I just looked at says it'll be somewhere in the range of 0.45-0.6 g/hr for 1/2 load (depends on gen model).

On the other hand, TANSTAAFL. If you're running this off your engine alternator, your engine will be working harder and your fuel consumption will be going up. Maybe not quite as much as the generator would take, but I would expect you'll burn at least another .25g/hr. So how much are you actually saving, for a LOT of up-front expense and ongoing maintenance. You'll have to replace a lot more batteries in a few years than you would now.