update converter

[Justme44]

I have to decide if I am going to install a full house inverter/charger (2k) or just update the old Magnatek single stage charger. If I update the converter I will need some kind of AC so I can use my CPEP at night. My question is, can I (2000 3280) punch a hole in the floor of the front closet into the battery compartment and put a small inverter (250W)in there and run the AC into the front bedroom thru that hole in the closet?

[mjammersc]

If your only need is the CPAP machine, I would look at a small inverter (eg Morningstar SureSine 300W) install vice a large one as they are more efficient and you can do an install running the power where you need it vice going into the main power panel/AC distribution.

[jcurtis934]

If your front closet is really over the battery compartment, mine sure isn't. Look carefully at how much overhang you have. You can remove the plastic covering from the overhang area to expose any ac and dc wires running back to the battery compartment and to safely add an additional. Since you mention 250watt inverter, which will supply less than 2 amps of 120vac, is this more than what the machine needs? If you were running the infected all out against the top of its specification, it will be sucking about 20 amps of 12 vdc out of your battery. If you had a single 75 ah 12 vdc battery, you will reach the maximum discharge point for this battery in only 1.75 hours. Hope this helps guide you. John

[WaltBennett]

The main thing is to put your inverter as close to the batteries as possible - ours is in the basement next to the wall between it and the batteries. You want the shortest DC run and 6 gauge 0r larger wire. The AC run can go ten feet or better with no problem, but DC doesn't like that. I'd think you could put your small inverter at the top of the basement wall, drill a hole to pass cables into the battery compartment, and then figure out how to route an extension cord to your bedroom or put an outlet in it somewhere.

Another concern should be how much battery you'll need to run your machine and how it (they) will be charged. Small 'Kill-A-Watt' meters aren't that expensive, and will tell you what the real current draw is, both starting and running. I suspect you may need at least two very large 12v deep cycle, or maybe even four 6v golf cart batteries. If you're not going solar, you will have to upgrade your converter to a three-stage. Read Jack Mayer's info on inverter/converters and the part about 'why not my converter' and you'll see why.

[Goin 4 Broke]

If I am not mistaken, most CPAP machines actually run on DC. Mine has an external converter. I would assume that running a dedicated 12v supply is much simpler. Just a thought.

[Bama Camper]

quote:Originally posted by Goin 4 Broke

If I am not mistaken, most CPAP machines actually run on DC. Mine has an external converter. I would assume that running a dedicated 12v supply is much simpler. Just a thought.

They do run on DC, but check the specs first - some require a different voltage. The voltage is usually written on the AC power supply or on the back of the machine.

Also, if you don't really need the heated mist, don't run the heater in the CPAP machine. It uses a lot of power.

[twindman]

I have used a 1000W inverter for 10 years now. I ran a heavy wire - don't remember the gauge tho - from the battery compartment up thru the hole that was used for hydraulic lines, I think. It goes into the bottom of the bed. Then I screwed the inverter to the slide portion of the floor at the edge of the bed. The cable flexes as the slide goes in and out, but since it has slack in it, it doesn't seem to wear out.
Oh, and I never use the heated water thing - just straight air so the amps are down.

[Justme44]

Thanks a lot for the information .. Looks like I can go with my plan ... will check the size of my battery bank to start .. I am installing 2 interstate DC2 6v batteries at 205 AH ($110 each at Costco)and up grading my converter to a Progressive Dynamics D4655 55 Amp 4 stage charger ($198 at Best Converter). I have also ordered the TST 510 Tire Pressure Monitoring System With 4 Sensors ($242). Being that my tires are a load limit of E, I have ordered 2 BF Goodrich Commercial TA As2 tires ($167 each at Walmart) because I can't afford to replace all 4 of the tires and the other 2 tires have a DOT date of 2 years old and look good. I am so grateful I found this site as you are all so fantastic with your knowledge of the Montana.