solar energy systems: DC cable loss

DC cable loss is a problem in solar energy systems working on 12 Volt or 24 Volt. Especially when the load takes a substantial current, the cable loss in a 12 V or 24 V system can get so high that the voltage drops below its minimum level. Example: A 120 load Watt in a 12 Volt system requires 10 Ampere... (Ohms law: U=IxR). When the cable is too thin and/or too long the voltage on the load can drop to 10 Volt or 8 Volt. Best way to supply a household with solar energy is to use inverters, the 110 V or 230 V AC at the output from the inverter suffers much less from cable resistance. So don't invest in "copper" but put your money in inverters. The cable from the battery to the inverter must be fused and thick and short (use the cable that is delivered with the inverter). If the battery-inverter cable is too thin or too long the inverter will quickly switch off (low voltage safeguard) due to the voltage drop in the cable. Your battery is still almost fully charged, but your inverter does not work because it detects a too low battery voltage. More info in my book "small scale solar energy systems (revised) ", on the Lulu website (author Ko Tilman).
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