How to choose the correct RV fuse
Before we start guessing which fuse for RV that we should use. It is important to know the Voltage, Current, and Power. These three items will always show up in your RV electrical circuits. Only when making clear of how they work you can never meet the potential problem.
Understand Battery Wiring
Firstly double confirm the voltage of your battery system in your camper. Generally there come 12V and 24V voltage. If you buy a pre-owned vehicle and have no idea of the house battery voltage, please follow this diagram to check the wiring and you can easily tell then answer.
What is the appliance power?
The appliance will draw the power from the house battery. Check the specification label of the loads. You will find XXX WATTS, which is the parameter of the power. You will easily find it on the backside of the load like this 120VAC/12VDC freezer fridge.
Start calculating!
Now let’s measure the current draw of the circuit. Generally, 12V DC load accepts a voltage range at 10.5~16.0V(×2 for 24VDC) for good working. Here is the formula for calculating correct Amp;
Max. DC load power(Watt) / 10.5VDC * 125% = Reasonable current for fuse(Amp)
- Some DC load will also work even battery is lower than 10.5VDC. For protecting battery ensure battery voltage is always higher than 11.0V.
- 125% is a good factor for allowing the DC load to start work with its surge power, as the 12V compressors. But please understand 125% is not a definite correct parameter. Please consider increase or decrease this factor.
For Example, the 12VDC freezer fridge;
Wire the 12VDC, its rated power is 175 watts, but it also has a surge power when internal compressor working(inductive load).
175 watt / 10.5VDC *125% = 29.8Amp
Therefore choose the 30Amp fuse.
Optimize the electrical circuit
You may already have the single fuse and fuse holder to protect each specific circuit. But if you have multi-circuit DC loads and the mass wiring without management will cost a lot of time to find out the fault circuit by the voltage meter. Let’s get optimize it!
Popsail provides the 12-circuit fuse hold set. It can be used as the DC distribution panel to protect your DC loads working, like LED lights, RV vent fan, 12V(or 24V) freezer, 12V(or 24V) water pump, etc.
comprehensive interface with the fault LED indicator. As soon as the fuse is burnt or the DC cable wiring gets loose or break, LED on the specific circuits will ON and you can easily find “who is the bad boy”.
Never forget to use the correct gauge cable
After installation of the fuse holder box, please select the high-quality power cable as the following chart;
