FAQ - Battery Management Systems
Q - Is the National Luna split-charge system a parallel system or independent system ? A - The National Luna split-charge system is a parallel charging system. This means that the MAIN vehicle battery and the AUXILIARY battery are charged at the same time and are connected in parallel.
Q - What is the best auxiliary battery to use ? Deep-cycle or high-cycle ? A - There is no "best" battery to use. If you need a fast-charging battery, use a high-cycle battery. Remember that this type of battery must not be deep discharged and must be re-charged soon after any discharge. As the name implies, a deep-cycle battery can be discharged to 20% capacity but it will recharge slowly. It is important to choose a high-quality battery designed for automotive use.
Q - Can I install more than one auxiliary battery ? A - Yes. Additional auxiliary batteries can be paralleled with the first auxiliary battery. This will increase the size of the auxiliary battery bank capacity. It is not recommended to mix high-cycle and deep-cycle batteries in the auxiliary bank. It is essential to make sure that your vehicle's alternator is appropriately rated for this load.
Q - Where do I install an auxiliary battery in my vehicle ? A - Every vehicle is different and installation will depend on available space. Try to keep cables as short as possible in order to minimize voltage loss. If you need to install an auxiliary battery outside of the engine compartment, consider a Portable Power Pack or suitable battery box.
Q - How accurate are the National Luna battery monitors ? A - The National Luna battery monitors are accurate to 10 millivolts. The displays of the monitors are graduated into specific voltage thresholds, meaning that voltages between two thresholds are not shown. This is important since actual battery voltage may be higher than the displayed voltage on the monitor but less than the next voltage threshold.
Q - Can I use National Luna battery monitors with any split-charge system ? A - Yes. Since the National Luna battery monitors are designed to be coupled directly to the application battery, it does not matter what type of split-charge system is used, if any. There is one exception - the National Luna Dual Controller is designed specifically to match the National Luna Split-Charge systems.
Q - Can the National Luna Split-Charge system drain my batteries ? A - The National Luna Split-Charge system consumes less that 1A when the vehicle is running and less than 40mA in standby. It is therefore not possible for the Split-Charge system to drain batteries over a short period of time. If the vehicle is standing for long periods of time (a few weeks), the batteries should be disconnected to prevent discharge.
Q - Can the National Luna Split-charge system be installed in a trailer or caravan ? A -Yes. Since no ignition wiring is required, the system can be installed just about anywhere. Keep in mind that the longer the cable length, the more volt-loss can be expected. It is recommended to use good-quality welding cable for long cable lengths.