To buy a generator or not...
Looks like we will be taking a week long camping trip up to Lake Syskyou near Mt Shasta, CA the second week of August. We looked at the weather forecast and the temps look to be ranging in the 90s to ...
Forum Discussion
Hi,
I've been able to run the roof air since 2011--just not for as long as I would like (without a generator).
Keep the existing batteries and spend the money from the savings on LiFePo4 for solar panels, a much larger capacity charge controller, and a large inverter/charger (Victron?).
You may find that with enough solar the existing batteries will get you through a day.
The problem with a dc to DC for the alternator is duty cycle. If the alternator is 130 amps (as mine is), it may be designed for a 1/3 duty cycle--in other words, only about 43 amps. That is why I chose a dc to DC that maxes out at 20 amps--because they are HUNGRY on the input side and draw 30 amps to output 20 at a higher voltage. That gives me some head room for other electrical needs. As it is--my solar panels send energy to the engine, when the sun shines.
If you want to try larger--there is a 40 amp from renology that has a jumper that can be removed to drop it back to 20 amp.
The solution is to replace the alternator with one that is continuous duty, and/or have an external diode. The continuous duty is better (and costs a lot).
My own plan is now to do a massive upgrade to the solar (1400 watts fixed flat) and see how the existing battery bank reacts. The RV has been in storage for 18 months now.
I've been able to run the roof air since 2011--just not for as long as I would like (without a generator).
Keep the existing batteries and spend the money from the savings on LiFePo4 for solar panels, a much larger capacity charge controller, and a large inverter/charger (Victron?).
You may find that with enough solar the existing batteries will get you through a day.
The problem with a dc to DC for the alternator is duty cycle. If the alternator is 130 amps (as mine is), it may be designed for a 1/3 duty cycle--in other words, only about 43 amps. That is why I chose a dc to DC that maxes out at 20 amps--because they are HUNGRY on the input side and draw 30 amps to output 20 at a higher voltage. That gives me some head room for other electrical needs. As it is--my solar panels send energy to the engine, when the sun shines.
If you want to try larger--there is a 40 amp from renology that has a jumper that can be removed to drop it back to 20 amp.
The solution is to replace the alternator with one that is continuous duty, and/or have an external diode. The continuous duty is better (and costs a lot).
My own plan is now to do a massive upgrade to the solar (1400 watts fixed flat) and see how the existing battery bank reacts. The RV has been in storage for 18 months now.
