Sorry in advance for the lengthy text. Trying to anticipate questions in advance so there is not a lot of back and forth. So here’s my dilemma. I have a small camper and currently have a 1000 watt modified sine wave inverter (Dewalt). It has run my medium size residential type fridge and 46 inch smart TV just fine for well over a year when I’m not on shore power. I sometimes live in it for extended periods, a month or 2 here and there.
Recently added 500 watts of solar to my battery bank of 700 amp hrs of Duracell group 31 deep cycle batteries so I rarely plug in to shore power anymore. I have room for a little bit more solar and a couple more batteries if I need them.
Problem is, my little 1000 watt inverter (modified sine wave) won’t run my microwave, induction cooktop, or the Keurig coffee machine. I have to be on shore power to run those.
Simple solution is to have Bezos deliver me a 12 volt 3000-3500 watt pure sine wave inverter and be done, right? About $350-400 for one with a remote switch and digital readout.
OK, now for the dilemma. I hear the mantra often “double the volts, half the amps”. (You know who you are ). Obviously, I have enough batteries in the house bank to series 3 sets of 2 for 24 volts. (and still have one left over, I could add another so I would have an even number). A dear friend has offered me a Magna Sine 24 volt pure sine wave 4000 watt inverter/charger for free. Presumably just needs a circuit board which I hear are easily replaceable. This thing goes for about 1700 bucks new and presumably is built to last a lifetime of continuous use.
Problem is, everything on my vehicle is set up for 12 volts, including the starting battery bank (2 12 volt group 31 starting batteries). So, is it worth it to use a step down transformer for all of my 12 volt needs just to get the efficiency of a 24 volt system? The solar system will be fine with charging a 24 volt system by the way. Also, wire runs are pretty short so not much loss there.
Another thing is, I have a Blue Sea ACR (automatic charging relay) which links the 2 battery banks when either one of them hits 13.6 volts to charge the other one. This is handy when driving as the alternator puts out a great deal of current. Also handy when parked as the overflow solar power keeps the starting bank topped off she is sitting for a while. Seems like I would lose this neat advantage if I switched the house bank to 24 volts. Obviously, losing the ability to electronically connect the 2 banks via a cab mounted switch would be disappointing should the need arise for mucho amperes, like a boost or maybe a winch down the line.
Was thinking this beast (The Magna) might be big enough someday to power an air conditioner if the ACs and solar become a little more efficient. But that’s a subject for a whole other thread.
I know there are some cool folks here that are way better at this stuff than me so I thought I would throw this out to the forum for some feedback. I really appreciate any advice and ideas. Should I go the simple route and stick with a 12 volt inverter or make the modifications to up the input voltage to 24? Would it really be that much more efficient?
Thanks in advance!
ROCKY
Excuse the messy wiring. Still cleaning it up after adding the solar array.
Recently added 500 watts of solar to my battery bank of 700 amp hrs of Duracell group 31 deep cycle batteries so I rarely plug in to shore power anymore. I have room for a little bit more solar and a couple more batteries if I need them.
Problem is, my little 1000 watt inverter (modified sine wave) won’t run my microwave, induction cooktop, or the Keurig coffee machine. I have to be on shore power to run those.
Simple solution is to have Bezos deliver me a 12 volt 3000-3500 watt pure sine wave inverter and be done, right? About $350-400 for one with a remote switch and digital readout.
OK, now for the dilemma. I hear the mantra often “double the volts, half the amps”. (You know who you are ). Obviously, I have enough batteries in the house bank to series 3 sets of 2 for 24 volts. (and still have one left over, I could add another so I would have an even number). A dear friend has offered me a Magna Sine 24 volt pure sine wave 4000 watt inverter/charger for free. Presumably just needs a circuit board which I hear are easily replaceable. This thing goes for about 1700 bucks new and presumably is built to last a lifetime of continuous use.
Problem is, everything on my vehicle is set up for 12 volts, including the starting battery bank (2 12 volt group 31 starting batteries). So, is it worth it to use a step down transformer for all of my 12 volt needs just to get the efficiency of a 24 volt system? The solar system will be fine with charging a 24 volt system by the way. Also, wire runs are pretty short so not much loss there.
Another thing is, I have a Blue Sea ACR (automatic charging relay) which links the 2 battery banks when either one of them hits 13.6 volts to charge the other one. This is handy when driving as the alternator puts out a great deal of current. Also handy when parked as the overflow solar power keeps the starting bank topped off she is sitting for a while. Seems like I would lose this neat advantage if I switched the house bank to 24 volts. Obviously, losing the ability to electronically connect the 2 banks via a cab mounted switch would be disappointing should the need arise for mucho amperes, like a boost or maybe a winch down the line.
Was thinking this beast (The Magna) might be big enough someday to power an air conditioner if the ACs and solar become a little more efficient. But that’s a subject for a whole other thread.
I know there are some cool folks here that are way better at this stuff than me so I thought I would throw this out to the forum for some feedback. I really appreciate any advice and ideas. Should I go the simple route and stick with a 12 volt inverter or make the modifications to up the input voltage to 24? Would it really be that much more efficient?
Thanks in advance!
ROCKY
Excuse the messy wiring. Still cleaning it up after adding the solar array.
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