RV install

lipets
lipets Solar Expert Posts: 61 ✭✭
I have a motorhome that had a propane fridge that had problems, I just installed a small 10 cu ft residential fridge.

In fact many rv's are doing this due to fire hazards with the propane units.

I also have a microwave but don't use it much, cook and heat water with propane.

Then just the lighting with led's and a TV along with two laptops.

There is one AC panel which also has the 2 AC's, Hotwater heater which I don't intend to use unless plugged into shore power with a 50 amp input which goes thru a switch that is tied into a 7500 watt generator.

I have 2 6v batteries for engine starting and 4 6v for the house batteries.

Over the last two weeks I've been researching an install intending to get about 400-450W panels.

Generally most RV use a 1500 - 2000w inverter charger.

Shopping for the inverter is daunting, some are $900 others $1600

I would like input what brands I should focus on or best bang for the buck

I see the zantrex sw 2000, magnum highest price and several others.

Here are a few with some costs online

Cotek ST2000-112 2000W Pure Sine Inverter Transfer Switch $700
or
Samlex America SA2000K112 2000W Pure Sine Wave Inverter $690
---
Tripp Lite PV2000FC $384 PV1800GFCI
Go Power! GP-SW2000-12 $823
Magnum MS2012 2000W $1500
OutBack Power FX2012MT $1587

Then the controller, the Bogart is releasing a new one soon SC 2030 which looks interesting.

I understand the wire sizing and install in general.

But if I can get some input on these two components I can see what else I need.

tks

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: RV install

    In general, RV systems usually want to be pretty small and efficient... I.e., a 300 Watt TSW (True Sine Wave inverter) range--At least for most of your "critical/sensitive" loads.

    If you have larger loads on occasion, some folks will have a second/bigger MSW (cheaper) or TSW (more expensive) inverter to power on when needed.

    As soon as you add a "refrigerator"--Your AC inverter is probably in the 1,200 to 1,500 watt range (refrigerators have about a 5x running current for starting... 120 Watts running means ~600 VA starting, plus a few other loads).

    And your daily power needs go from under 1 kW per day to over (guessing) 2.5-3.3 kWH per day (again pure guessing).

    Do you have a kill-a-watt type meter you can plug in to your major loads for a few days (each) and get your average daily power usage?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • lipets
    lipets Solar Expert Posts: 61 ✭✭
    Re: RV install

    Bill in order to that (meaning two inverters) I would have to split the ac panel and trace all the outlets, all of which are buried in the walls.

    So I think I want to just use one PSW inverter and just run one wire to the ac panel.

    The fridge isn't here yet to measure anyway with a kill a watt.

    Almost all RV's use 1500-2000W units and they all appear to work.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: RV install

    depending on the distance from batteries to where you can mount your inverter , assuming 12V, you may find that the proper ga wire for a 2000W inverter may be prohibitive as it will need to be quite large.
    If you can, check out what size is recommended and be sure it will handle the surge load.
    If possible investigate a 24V system as the wire needed will be a fair bit smaller. I used #2 on my 1500W 24V inverter over 2 feet just to be sure, used to run a fridge and other kitchen appliances.
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • lipets
    lipets Solar Expert Posts: 61 ✭✭
    Re: RV install

    there are two compartments next to each other one with the batteries the other has a converter which will be replaced with the new inverter.
    So the run of wire will be very short.
  • lipets
    lipets Solar Expert Posts: 61 ✭✭
    Re: RV install

    Someone asked what the Fridge draws, I found another post with the same unit.

    Startup on this is about 5A. Running is less than 1A. According to the kill-o-watt it consumes just under 1Kw [actually 1 kWatt*Hour -BB] in 24hrs

    Can anyone give me their opinion on two things, a 1500-2000W psw inverter/charger with a passthru for AC, I listed a few in my first post.

    Secondly a controller.

    Just looking for the best bang for the buck

    tks
  • zoneblue
    zoneblue Solar Expert Posts: 1,220 ✭✭✭✭
    Re: RV install

    It used to be that solar was costly and fridges not so much so. Then the rule was effcient fridge, less solar. Now that tide is turning the efficent fridges cost more than the solar to power them. BUT... on an RV, there is a major space constraint for PV usually, in addition to shading, flat hot surfaces etc. So my view is that it still leaves you firmly in the get-the-most-efficient-fridge-you-can-find territory.

    Unless you are plugged in all the time, in which none of this is an issue.

    Id also be pricing 24v fridges, theres some quite nice ones targeted at the marine market. eg http://vantagervltd.vpweb.co.nz/apps/webstore/products/show/4334856
    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,
    http://zoneblue.org/cms/page.php?view=off-grid-solar


  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: RV install

    No reason to remove the converter when you install an inverter, they serve different purposes, and in most RVs the converter also acts as your AC utility panel. Forget trying to power the A/Cs, microwave, or an electric heater from the inverter. Size yours much smaller to power things like your laptops.

    I've been active in the RV community for a very long time, currently active on several RV boards and an admin on one, and I've never heard of people removing them due to fire worries. There is the rare person who replaces one with a dorm fridge because the original fridge dies, like you, but not due to a fire worry.

    All fridges use a ton of energy which is why ammonia absorption fridges exist. A dorm fridge just uses a ton of electricity. A RV fridge also uses a ton of electricity in DC or AC mode - but propane is a dense energy source and efficiently provides what the ammonia cycle needs - heat. You can go a month on one 20 pound LPG tank.
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is