Inverter/Converter and Charging questions

[harleyman134]

I bought a 2005 MADP 4304 back in July, this is my first RV and it has been like "baptism by fire". We are going to the RV Supershow in Tampa later this week, so last week I went to the storage facility to take the MH for the Norcold recall, the chassis batteries were dead and I had to replace them. I've been concerned about my batteries every since I bought the motorhome and wound up replacing the house batteries as well. Since then I have been trying to figure out the best way to "maintain" my new batteries.

According to the brouchure for my MH I have a 2000 watt inverter and a 75 watt converter. I have a pretty good idea of how to use the inverter, but I though the inverter also charged the batteries. I just push the battery charge button on the magnum remote and it will show my batteries "charging". Now I'm wondering if the 75 watt converter is actuallly charging the batteries and when I'm in the magnum remote panel setting up the charging paramaters if I'm setting up the inverter or converter. I'm using 4 6volt golf cart batteries wired in series for two 12 volt banks, so based on what I've read I have 440 amp hours with this setup. My other confusion is what "amps" do I need to set up in the remote panel to properly charge these batteries, some web sites I've been to state to use amp hours divided by 10, and other web sites state to use amp hours divided by 5. So I need to set up the amp to either charge at around 44 or 88 amps. This is all rather confusing to me and I'm sure I haven't explained my questions very well, but if anyone could help I would appreciat it.

Sonny

[GaryKD]

I can not help you with the Magnum, I'm sure others will jump in. Are you attending the Super Show with the Newmar Kountry Klub? We have our own parking section and a tent to host mini-events. On Friday at 5 PM there will be an iRV2 Social. If you are not attending with the NKK group, feel free to come over to the tent and enjoy a social with your iRV2 buddies. We will be at the North West corner of the fair grounds. From the Newmar coach display go directly West and exit the show. Keep going West and you will see the tent.

[harleyman134]

Quote:

Originally Posted by GaryKD I can not help you with the Magnum, I'm sure others will jump in. Are you attending the Super Show with the Newmar Kountry Klub? We have our own parking section and a tent to host mini-events. On Friday at 5 PM there will be an iRV2 Social. If you are not attending with the NKK group, feel free to come over to the tent and enjoy a social with your iRV2 buddies. We will be at the North West corner of the fair grounds. From the Newmar coach display go directly West and exit the show. Keep going West and you will see the tent.

Gary,

Thanks for the invite, we are pretty much on our own, we will be getting to Tampa on Thursday and going to the show on Friday and Saturday. We are planning on going to the Newmar display and will try to get over to your tent. As far as my original post, it helps me to put stuff in writing and since posting my message I've pretty much figured out what I have and how most everything works. I still have a question regarding the charging amps to use. The owners manual for the Magnum inverter I have suggest I use the 88 amp rate and another article about the 12volt side of life suggest the 44 amp rate. If I can get this worked out I'll feel like I have a pretty good handle on the battery side of things. You know as soon as I think I have something under control I find out something else I need to learn.

Sonny

[GaryKD]

Hi harleyman134,
I know exactly how you can determine what to do. Bring your Magnum book to the Newmar tent. Newmar will have techs at this rally. I'm sure there will be a Newmar tech who can answer your question.

In addition to the iRV2 social on Friday, I host a NKK Sea Turtle Chapter rally on Thursday at 4 PM. Feel free to drop in and spend an hour with a chapter. It will be located in the same tent as the iRV2 social.

["007"]

Sonny, your 75 watt converter will be charging your batteries through the BIRD system in your coach.
With your shore power connected the house batteries will be charged first than when at full charge the chassis batteries will be charged but with the house batteries having preference if your using your 12v systems.
Your BIRD unit maybe in rear compartment drivers side hidden behind panel on rear of compartment.
If you replaced batteries make sure they are at full charge by using a battery charger and the Bird will maintain them at full charge.



MORE information about Bird and related DP info and location of Bird in DP note post #29.

[wa8yxm]

you have a 2,000 watt inverter and a 70 watt converter? Converters are almost never rated in watts,, Do you mean a 2,000 watt inverter, a 70 AMP converter and let me guess

A pair of six volt golf car batteries in series for a battery?

This would... But about right.

[davecampbell]

"The owners manual for the Magnum inverter I have suggest I use the 88 amp rate and another article about the 12volt side of life suggest the 44 amp rate. "

The ONLY reason to charge ANY battery at a 44 or 88 amp rate IS TO DESTROY THEM.

According to Exides engineering dept (not a mechanic) the MAX charge rate for a GC-135 (as an example) is about 25A, and frankly, thats a bit much.

"converters" are rated in watts. V x A. Simple physics. PS they arent converters, they are DC power supplies, both the inverter and power supply are converters. Anything that changes energy forms are converters.

Its a 12 VDC power supply, and yes, they are rated in watts.

Notice the black box has only one relay output, which means it is not able to, contrary to the Intellitec documention, to charge one battery bank THEN another, it charges one then crow-bars the second across it, which can destroy BOTH banks due to high currents. Miserable design.

[wa8yxm]

Dave. Excide batteries do not have the best rep among users.. However that said... your last paragraph makes no sense at all.

And Converters are normally rated in the AMPS OUT, at least every one I have seen and I have seen quite a few between looking at them in the store, shopping for them on line and designing my own for some uses.... Every one EVERY ONE, posted the amprage rating in very big letters.. (Yes, wattage was in fine print on the id label cause that is required but it was the AMPS OUT that they posted in big bold numbers)

Xantrex says to use the 30% capacity as the max for most batteries (Less for gel cells) Lifeline suggests 30% as the minimum and Trojan 10% max

That's percentage of the 20 hour amp hour capacity of the battereies

So for the common GC-2 size it means about 66-70 amps more or less

(220 to 235 depending on who made the battery times 30%)

Add in a few loads from the lights, and such, or add in the chassis battery on a motor home and 80-88 is within line.

[alan1]

I have attached the set-up manual for your remote. I would go through all of the set-ups as mine was not set correctly when I purchased it. The house batteries were boiled dry and when reviewing the set up the charge was set at 100%. My 2000 watt inverter charges at 100 amps. You set it up (the remote) as a percent of max charge rate or 100amps x 80% gives a 80 amp charge. Again I would go through all of the set-up on the remote. Your charge rate of 88 is correct according to the Magnum remote info.

[Norm4015]

If you have the factory installed inverter/charger you do not have a converter. In your model year the converter was probably standard, but when Newmar installed the optional inverter/charger they eliminated the converter.

["007"]

Thanks for that link Alan1 lot of information to absorb on that link plus changing setups if you were to change types of batteries.