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| Fuse | current rating | |
| battery fuse | XEV25-175 | 175 |
| Charger fuse | XEV10-50 | 50 |
| Motor fuse 1 | XEV20-80 | 80 |
| Motor fuse 2 | XEV20-80 | 80 |
| Solar fuse | XEV10-20 | 20 |
| Pre-charger fuse | XEV10-5 | 5 |
| DC DC fuse | XEV10-5 | 5 |
For the lower-current fuses (Solar, Pre-charger, DC-DC), we will be using the axial bolt-on type.
Alternate Sources for fuses (since COVID happened and Eaton was not going to sponsor for a while)
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Note On Interrupting Rating:
Fuses on our HV system should be able to project against a short circuit condition on the cables they are connected to. So what's the short circuit current?
The max current available from our batteries will be at their highest voltage, since a short circuit is just a resistive load. Maximum condition calculations will assume that the external short is 0mOhm, and the only thing limiting the current is the battery's internal resistance. This is a reasonable estimation as it will ensure an adequate safety factor for our fuses. Since our modules are in series, we only need to do the calculation for 1 module.
Voltage: 4.2V
Internal Impedance (using AC since a short circuit is a transient event, and AC IR is lower than DC IR typically): 25mOhm (ish - rough value of what was observed)
Short circuit current per cell (Iscc) = 4.2/0.025 = 168A
Short circuit current per module = 168A * 25 cells = 4200A = 4.2kA.
So all of our fuses must be rated to break a minimum of around 4.2kA.