48V RV power system on its road

2021-05-16

Most RVs or mobile energy pack utilitze 12Vdc system to power the 12Vdc appliances. Any new decisions of increasing the energy capacity will be always related with "increasing voltage" or "increase amperage". 

Adding another new 12V batteries in parallel to get more amperage with a constant voltage is a general option for most RV owners or RV manufacturers. It is workable and easy to do, but this system does need a larger guage of wires to ensure the system safety. More amps through the wire the lower energy delivery efficiency will get. Just like the traffic flow--more vehicles go through the road the lower speed it will reach,  therefore more heat going through it. More heat means higher potential for a blown fuse, tripped breaker or even fire hazard. 

48 volt systems strike a balance between increasing capacity without increasing the danger.

1. 48VDC < 60V DC, therefore 48VDC system is still a low voltage system as far as it goes, which has implications for how we run wiring.
2. 48V is relatively common among house back-up energy system or off-grid systems, which means there are wide options and selections of inverters and battery chargers. For example it is not easy to find a 12V 4000W inverter charger but it will be easily for you to get a 48V 4000W inverter charger. 
3. 48V system is an ideal option for inverter boost motored loads in RVs. As it only requires 1/4 amperage of 12V system. 48V systems has this benefit of increasing power to components without raising the current (amperage).

4. As the benefit of Point.3 as above, without increasing the current there is also no need to upgrade the cable guage. Thus 48V system asks the smaller guage of cable for DC wiring.

5. 48V increase the efficiency of power delivery: RV PV array ---- MPPT solar charger ---- 48V battery bank ---- 48V inverter(inverter/charger) ---- Appliances in RV. A higher voltage comes the power delivery efficiency will get higher. Therefore there comes less power loss and heating.

What you need to prepare for 48Vdc RV system?

1. 48V battery bank, which can be get by wiring 4pcs 12V AGM battery, or purchase a 48VDC Lithium battery pack directly. Please note most 12VDC lithium battery cannot be wired in series!

2. 48VDC inverter(or inverter charger). 

3. MPPT solar charger for 48VDC battery bank.

(4.) 48VDC hybrid solar inverter(inverter charger + MPPT solar charger combination)