HELP! Power Converter Upgrade Time

wbryanh · January 08, 2018, 11:02 AM

Hey Guys,
Time has come in my revitalization project to replace this Progressive Dynamics PD696 Power Converter. Any advice and/or suggestions on what to replace this oldie goldie with? Any help is much appreciated!

Thanks,
Bryan

khantroll · January 08, 2018, 12:11 PM

Generally speaking, the go-to for replacement converters are the Boondocker series from BestConverter.com http://www.bestconverter.com/Boondocker-Converters-_c_154.html

Also, if you haven't, please check out the following topics:

http://www.classicwinnebagos.com/forum/index.php/topic,5326.0.html

http://www.classicwinnebagos.com/forum/index.php/topic,5975.msg56511.html#msg56511

http://www.classicwinnebagos.com/forum/index.php/topic,9224.msg47465.html#msg47465

The last one presents a slightly cheaper alternative to the Boondocker converter

wbryanh · January 08, 2018, 12:47 PM

Thank you for the links, I will definitely give them a read. Electrical is not my expertise!

Let me go a little deeper by saying my Winnie is a conversion project. It will not be used as a living space. I am converting it into a Mobile Boutique for my wife. As of right now, I only need power for interior overhead lights and a few outlets (for small appliances). Eventually I will be add a new air conditioning unit overhead.

I would like to keep the shore power option as well as the generator.

khantroll · January 08, 2018, 01:05 PM

The converter performs two functions: it charges your house batteries when connected to shore or (in some or most cases) generator, and it supplies 12v power to your 12v systems when you plugged into shore or generator power.

With that in mind, you can probably get away with leaving the stock convertor, or an inexpensive one from ebay or a wrecking yard, because you'll be mostly using it as a 12v source.

wbryanh · January 08, 2018, 01:12 PM

Sounds good.

What size do you think would be adequate for my needs? Again, I am running overhead LED lights in the ceiling, probably (2) wall outlets and eventually adding a roof AC.

I see PowerMax makes several lesser models. Do you suggest any of them?

khantroll · January 08, 2018, 04:08 PM

Well, this is where we have to get some math involved. What sort of house battery will you be using, and how many? The will determine how much current the battery bank can accept, and thus the size of the converter.

Rickf1985 · January 08, 2018, 06:52 PM

The AC really doesn't fall into the equation since it will be 110 volt and what you are looking at is the 12 volt side of things.

wbryanh · January 08, 2018, 09:53 PM

Kahntroll,
My rig currently has two batteries in the battery compartment. I know one of them is a marine type battery. (I can explore further tomorrow, as I keep the Winnie in my office warehouse).

Thanks Rick, you are correct!

wbryanh · January 09, 2018, 08:19 AM

Khantroll/Rick,
This is what I have in the battery compartment.

Rickf1985 · January 09, 2018, 09:09 AM

That is not a good combination for a couple reasons. You should have matched batteries in size and age so that one does not pull down the other. Since you are not going to be using this for extended boondocking or long periods of running off of the batteries I would suggest you get a pair of deep cycle group 24 or 31 size batteries for in there. Look for true deep cycle batteries and not marine type which are combination deep cycle/starting batteries. A true deep cycle battery will not have any CCA rating, it will only have a reserve capacity rating. They are not designed to start a vehicle at a quick high amperage but they are designed to put out power at lower amperage's for a long time.

khantroll · January 09, 2018, 09:42 AM

Hi,

I did some digging, at the marine battery is rated at 75ah at the C20 rate, so it's charging rate is recommended to be about 7.5 amps in the bulk phase. I don't know what your starting battery is, but I'd say it's probably fair to say it's in the 10 amp charging range. If lights are all you intend on running on the DC side, you can probably use a 45 amp converter. If you want to use other DC appliances, such as the furnace or fridge, you'll need more (or else it will eat into the battery charging current available).

wbryanh · January 09, 2018, 10:18 AM

Rick,
Those are the batteries that were in the Winnie when i purchased it 6 months ago. So you suggest getting two new ones? Of the deep cycle type?

Khantroll,
Thanks for your help. Would I be better off to go with a 55 just to be safe?

wbryanh · January 09, 2018, 10:31 AM

Here is another question.... Could I just run the 12V LED lights straight off my battery? Being that they may be the only need for 12V power and they do not draw much at all?

khantroll · January 09, 2018, 11:05 AM

Well, short answer is "yes". But here's the thing: you have to recharge the battery somehow at some point. Running it off the engine will take a minimum of 1 hour. If you hook up the converter just to charge the battery, you might as well tap into the feed from it (the way it is wired right now), because the top of the charge to the battery will go out to the lights.

The only other alternative would be to use a separate battery charger.

But yes, you can leave the converter disconnected and run the DC off the battery.

Rickf1985 · January 09, 2018, 11:15 AM

To answer your question to me, yes, I would replace them since they do not look like very new batteries and they are definitely not a matched set. One will always be draining the other. If you start new now then it is something you will not have to think about again for 5-6 years. As far as the charger/converter, I am not sure how the older Winnies are hooked up but a lot of them have a separate tap for the converter to supply 12 volts to the coach while plugged in separate from the charging system. I am running a 45 amp in my 89 and I have no problems with the heater or anything else. You will not be able to run the fridge on DC on any charging system other than a running engine since it is a very high amp draw and is only designed to be run in that phase during travel. If all you are using is lights then you could just buy an automatic type battery charger that will go into float mode when the batteries are charged but those chargers are about as much as the charger/converter that would go in the coach so why not just put in what belongs there and be done with it. That way you get to where you are going and pull out the cord and plug it in and you are done.

wbryanh · January 09, 2018, 11:46 AM

Excellent responses guys! I appreciate both of your feedback and assistance! Without this forum there are several areas I would have been stuck during this remodel. Thanks!

wbryanh · January 09, 2018, 01:32 PM

Rick,
Any particular deep cycle battery brand you recommend? (2) 12V or (2) 6V?

Rickf1985 · January 09, 2018, 04:32 PM

That is kind of like asking which is the best motor oil.

Ask ten people and get 15 different answers. DEKA makes good batteries but the general consensus seems to be the Trojan brand is the go to brand. You also have the option of going with two 6 volt deep cycle batteries and hooking them in series. You will get 12 volts and more reserve capacity. It is sometimes easier to find true deep cycle batteries in 6 volt. There is a tech article on batteries and I think we have it here in our tech section. I will look after I close out this post and if it is there I will link back to it.
Couldn't find the one I was looking for but this will give some good info.

http://rvservices.koa.com/rvinformation/rvmaintenance/what-you-need-to-know-about-your-rv-batteries.asp

TerryH · January 09, 2018, 07:13 PM

This, in conjunction with Rick's link may help:

http://usbattery.com/info-center/configuration/

yellowrecve · January 14, 2018, 11:59 PM

I have a question. Are both batteries for the coach interior or is one a starting battery? Can not see in the picture, if the positive cables are tied together.

khantroll · January 15, 2018, 01:01 PM

Hi Yellow,

Judging by how they are set in the tray, it looks like the stock configuration. The black one would be a starting battery, while the blue one is functioning as his house battery. They are tied together with a solenoid so that the alternator can charge both, but the house system can't pull power from the starting battery and possibly strand you.

yellowrecve · January 15, 2018, 10:45 PM

Khantroll
I agree that is probably the way it is connected, but the talk was to replace those batteries with 2 DC batteries, which is wrong. I wanted wbryanh to be aware of the difference.

khantroll · January 16, 2018, 09:42 AM

It's not necessarily wrong . In my rig, I did away with the solenoid and I run 4 12v deep cycle batteries in parallel. I don't recommend most people do that, but it works for me. I've seen many people do the same thing with 4 6v batteries in a 2s2p setup, and I've even seen folks run 2 sets of 2 6v wired in series and keep the solenoid. Each of the above setups has pros and cons against the each other and against the default setup.