Documentation doesn’t say, do i need to add a 150a or greater fuse before the pmu?
Hi,
That is not really a PMU-related question, but let me explain in more detail.
There is a misconception that fuses are used to save the device in case of overcurrent. That is not true.
If the fuse blows, the device is already dead, or the wiring harness has a short circuit.
Fuses prevent the car from catching on fire in case of some electrical failure. Making a short-circuit on the battery without a fuse will usually create a red-hot piece of metal somewhere that can easily ignite something.
Do you need the fuse? For the PMU to work correctly, no.
Do you want the fuse? If you want to minimize the risk of catching fire, yes.
The safest option is to have a fuse on every positive wire coming from the battery, and you want the fuse to be as close to the battery as possible.
Where to put fuses and their size depends on the specific system and design. Do you have a single positive wire for everything? Do you have multiple positive wires from the battery? What is the maximum current in each wire under normal operating conditions?