Originally Posted by fkempf216
I own a 2015 Itasca Sunova 35G and want to replace the two house batteries with three deep cell batteries of the same size and amperage and relocate the engine battery to another compartment in a battery box. I also want to upgrade the inverter from a 1000 watt to a 2000 watt unit. I will be upgrading the battery wire size and 120 Volt AC wiring and breaker to 20 Amp from the existing panel to the new inverter and installing a sub panel next to the new inverter to install 15 amp breakers to handle the existing power needs. The space I have now for my 1000 watt inverter will accommodate a Xantrex Freedom X2000 unit without a built-in battery charger. (The size of a Xantrex inverter with a battery charger is too large to fit where the existing inverter is.) The present battery charger is located under the rear bed. My question is do I also need to increase the battery charger to a higher output amperage as well as the wires from the charger to the batteries? What size battery charger do I need for the additional house battery?
-- What size batteries do you have now? If they are not at least 100AH each even going to 3 batteries (300AH total) will be marginal to operate a microwave through the 2000 watt inverter.
-- What size charger do you have and is it a 3 stage charger?
-- With a 2000 watt inverter to operate a microwave/toaster/coffee maker/hair dryer it would be best to have 400AH of battery or more.
-- Do your best to measure the distance from the charger (converter?) under the bed to the battery location and then use a voltage drop calculator to determine the wire size. Here is a like to a voltage drop calculator: Voltage Drop Calculator - for single and 3 phase ac systems and dc systems
You want to have a voltage drop of no more than 3% however 1% or less is better.
-- For the charging current, plan on 25% of your battery capacity. 300AH then you want a charger of at least 75 amps.
-- How do you plan on charging your batteries? If you take your batteries down to 50% to 60% full it takes many hours (6-8 hours) of generator run time to get back to 100%. The last 15% to full charge is at low current, from roughly 15 amps down to 3-4amps as it approaches 100%.
-- If you only dry camp/boondock for 2-4 nights and then back on shore power for at least overnight then not getting your lead acid batteries back to 100% is not a problem. However if you do long duration dry camping (2-3 weeks) then not getting your batteries to 100% tends to sulfate the plates in your battery which reduces your capacity.
-- 400-600 watts of solar will really help.