here is probably the most important circuit in the entire Safety Box the pre-charge circuit, it tickles the capacitor inside the inverter with gentle current before shooting all of it down it's throat, this keeps the capacitor from blowing up
it consists of a relay and a resistor and utilizes the same fuse as the positive contactor in the positive circuit mentioned above
the white bar of soap looking block is a 15 ohm resistor
The precharge circuit does not utilize the fuse, it is part of it. The actual fuse in the circuit is actually one of the orange wires, the resistor, or the relay, which seems reckless...
The precharge resistor, orange wires, and relay is, however, protected by inference by that circuit board you plan to discard because it simply opens the relay when a fault is detected in the circuit, which includes those capacitors the "safety box" is determined not to blow up....allegedly. Shows how ignorance and strict reliance on Google can set your car or truck ablaze by tossing out a critical circuit element.
The Panasonic relay AEC51012 is, from what I can tell, a 400V 5A relay, which means the precharge resistor must be at least 80 ohms. It's allegedly 15 ohms, which means a peak inrush current of 26 amps into the inverter and through the relay...
Correction. The Arrow site as indexed is incorrect:
The relay is 10A, which make the min resistor size 40ohms.
Found the datasheet. Contacts are rated for 30 seconds at 30A. Again, the board planned on being thrown out will time the charge/discharge cycles of the precharge to ensure the relay specs are not exceeded, since the 15 ohm relay will peak out at 26A. This is an abuse scenario, not expected operation that may need oversight by the controller.
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