The heater for protection during testing is because Damien recommends using a very low rated breaker or fuse during testing, one that is fairly likely to trip.Dennis wrote: ↑Sat Oct 28, 2023 2:34 pm Hi Johu. I have other inquiries.
1. In this great video ( ) at time 59:12 to 1:16:23 Damien explained the principle of a cooker resistance in PARALLEL with the HV fuse to prevent damage by “back emf” or “spring tearing” analogy in the inverter transistor when performing tests. And, he mentioned that the main contactor is controlled by the inverter using pin 3 and pin 6 for precharge relay coil to prevent damage in driving mode. Isn't it supposed that to have the protection explained with the cooker resistance, during driving, the precharge resistor must be in parallel with the contactor and the HV fuse that are in series? Openinverter diagrams illustrate the precharge resistor in parallel only with the main contactor.
In actual operation, the OI diagram, with the precharge only routing around the main contactor is correct. In a real world application, you want a blown fuse to cut power to absolutely everything. Yes, this means a blown fuse can destroy your inverter, but it's better than continuing to pump electricity into you, or something else that has caused a short.
In a car, the fuse's job is to isolate the battery from everything in case of a short. In testing, the breaker/fuse's job is to prevent pulling too much power from the testing power source.