solar power questions cause i just dont know.

[97e350]

hey i am new to the rv world. i just got a 97 e350 tioga.it has one hooked up already, small single panel on top of ac unit. no clue what kind havent been on roof yet, in no hurry to break my neck. i have two dc24-140 mega-start batterys that are rated 500 cca and 625ca. plus whatever is under hood. the plugs only work when generator is on or power hook up. i have a small dc/ac that i hooked up stright to batterys. if i run 500watts an hour how many hours can these batterys give me? or do you only count amps?. i want to switch everthing over so i dont waste gas or propain. want to be able to cook stuff and watch tv, and use comphters.

[97e350]

very good info. thanks. ya i try to ask if i dont know, thats why am here.
will keep everything in mind while i plan it out.

[SteveAE]

Sorry, but a small panel on top of the air conditioner really won't do much at all (other than add some money to the manufactures pocket).

Take some time reading the solar posts here (and other places), ask lots of questions, and when you are ready, install system that will help you with your power needs.

In the meantime, figure out how much power you really need and look for ways to conserve (i.e.; change to LED lights). The fun part of this, is you get to use your rig while you are learning.

Steve

[RoyB]

Your planned 2500 WATT INVERTER connected to your battery setup will draw over 200AMPS of DC AMPS from your batteries to produce 120VAC @ 2500WATTS. You will need to have probably a 400AMP inline fuse between the Battery Connections and the Inverter to protect your wiring and connections.

This is alot of CURRENT to be pulling from a battery. Check your battery specs and you will find that a 85-100AH typical deep cycle battery will only produce 12VDC with this amount of current for 15 minutes or so. To be safe and not destroy your deep cycle batteries you can only expect to run them down to 50% charge state or around 12.0VDC.

Alot of of folks think they can replace their 120AC requirements when running off the power grid with a simple high wattage INVERTER. This is really not the case and a 2KW Honda type generator is the best bet. You can do this but you will need probably six or more batteries wired in parallel to even get 2-6 hours of use running a full 2500watts load.

I get by real good with my 600WATT PSW INVERTER setup running around 300WATTS of load for our home entertainment electronic items for three hours each night between 8PM and 11PM and adding in my normal parasitic load of 1AMP for the remaining 7 hours from my 255AH battery bank. This drops down my three 85AH battery to 12.0VDC by the next morning where I must re-charge my batteries using my 2KW Honda generator providing power to my trailer to run its on-board smart mode CONVERTER. I can re-charge my battery bank back up to around 90% charge state in three hours time doing this... Here on the East side of the US we have lots of generator run time restrictions in place which requires us to beef up our battery banks and run our 120VAC things off of an INVERTER when camping off the power grid. Generators are never allowed after 8PM at most public places.

It takes good planning to use INVERTERs and be able to re-charge your batteries each morning so you won't destroy the batteries. 15-20 minutes is not a long time to enjoy your loaded 2500WATT Inverter with just a couple of batteries in your battery bank.

Just passing along to get you thinking about what you want to do...
I'm sure others on here will pass along the same info...

It would also be very helpful to others on here when discussing these things if the proper name for your items is being used. You seem to be mixing the terms CONVERTER and INVERTER.

Please NOTE this typical configuration diagram of a 30AMP Trailer Electrical System that may help identify the major electrical items being used.


Roy Ken

[97e350]

the refrigerator runs on propane also not sure how much it uses yet. and the co leak detectors wires were cut. so i put one in from homedepot that uses a battery. i just dont know where am going to put a 2500 watt dc/ac converter if i only get 2 feet of 0/1 gauge to use. or can i use more then 2? i can work on cars and trucks but this kind of stuff, no clue.

[97e350]

thank you guys. any ideas what batters i should upgrade to? the box can fit batterys for 10 1/2 deep, 11 1/4 w, 16 1/4 L. the box is a litter bigger then that but need room for the wires. Thanks again for the help.

[Golden_HVAC]

500 watts is about 50 amps per hour if run from a 12 volt battery through a inverter to a 500 watt appliance.

However if you are using a 500 watt inverter, it is the maximum output, not what the actual load is. Much like your car is not going 85 just because the speedometer says that. If you are watching a 75 watt TV set, then the load is about 75 watts, expect the inverter to take in 7.5 amps at 12 volts and put out 75 watts.

Your 80 amp hour group 24 battery will not last very long. The factory installed a pair of golf cart batteries in my 1997 Fleetwood, and I wonder why you have such small batteries now. The golf cart battery set-up will provide 220 amp hours between them. The pair of 24 AH will only store about 160 AH under the best of conditions, but let the battery age a year, it will only be about 120 AH total between them.

THe solar panel is about 15 watts, might be 10 watts, anyway it is about useless. Less than 7 amp hours collected in a day in the full sun.

The propane and CO leak detectors will use about 10 amp hours daily, with the refrigerator about 35 AH. To make 35 AH daily, then a 120 watt solar panel needs to be installed, along with a controller. To make up for furnace usage, TV, and lights, another 100 - 120 watt panel will refill the batteries in one day.

There is another solar post tonight that I put in how I made solar panel mounts, and gave a link to a solar website with panels in the $1.20 per rated watt price range.

Good luck!

Fred.

[Ronald_D_buckne]

Ok it's not difficult, but it can be kind of disappointing. Simply count up your amps. Group 24 bataries typically have about a 95 standing amp capacity. 2 batteries=190 amps. Now your 500 watt ac load is bit confusing to me, If you a true 12 volt dc compressor drawing 500 watts that's about 5 amps per hour or just under 40 hours of operation. Now if the compressor is 110 volt and is being run through an inverter than that hour rate has been pretty much cut in half (about 17 hours tops). The question to be asked is how big are the solar panels? That's what will determine how fast the re-charge is