With 3 panels in series, the Isc is below the max input current of either controller.
For my 75/15 MPPT Controller for the solar on the side port (200 Amp Suitcase), Is a 15amp Circuit Breaker on both sides (Bat/PV) adequate here?
Short Circuit Current of my 200 watt suitcase is 11.72A
The Max Continuous load for the Victron 75/15 is 15 amps, the short circuit current is 15 amps.
PV side breaker 15 or 16A.
output side breaker: you want some headroom, as 15A through a 15 A breaker or fuse for 4 hours will cause significant heating. Standard formula is 1.25Ic<Ib<1.5Ic. Where Ib is breaker rating, and Ic is circuit current, in this case 15A, so you want a 20A breaker.
Note: Isc for a PV module is a different concept than short circuit or max load current elsewhere i.e. on a battery powered circuit.
PV modules are inherently current limited - so the max current they can supply into a short circuit is limited. MPPT controllers also specify the MAX input circuit current - so the module Isc must be less than that.
Battery circuits are only limited by the battery voltage and circuit resistance, so if the output (Battery side) of an MPPT controller was accidentally shorted, the current is huge, potentially 100’s of amps.
Thanks Mike for the advice
To reiterate
Victron MPPT 100/50 for the 600 watts wired in series of roof panels.
15Amp Circuit Breaker/Fuse on the PV side of Controller
60Amp Circuit Breaker/Fuse on the Bat Side of Controller
75/15 for the 200 watt Renogy portable suitcase. (FYI, The portable suit case is 2 x 100 wired in Parallel). The onboard Renogy Controller was removed for direct connection tion to the SAE Solar on the side port which connects to the Victron 75/15 MPPT PV Terminals.
15Amp Circuit Breaker/Fuse on the PV Side of Controller
20Amp Circuit Breaker/Fuse on the Bat Side of Controller
Thanks
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