Greetings. I have a 120amp breaker/cutout between 9 200 watt panels to the MPPT. This is installed just before the MPPT, protecting the ‘PV’ input side. In the system diagrams, I show that there is another breaker/cutout installed between the ‘BATTERY’ side of the MPPT, which then feeds into the LYNX 1000 distribution/shunt.
Should I even worry about installing a second breaker/cutout between the MPPT & the LYNX, as the LYNX has the MAXFUSE bridge, where I’m able to install a 120amp max fuse? Thank you…
120A sounds rather high for the PV input side to the MPPT. If you have several strings (sounds like 3s x 3p) - then the strings should be individually fused at approximately 16A.
The MPPT has an internal fuse on the battery side, and you can also protect the wiring / MPPT with a fuse in the LYNX - max rating should be about 90A (1.25X I). So the nearest rating to this is 100A. A breaker is not needed, except for easy disconnection - not normally required.
Thank you. I appreciate the insight. I paid for a system, which was void of any real instructions. I have 3 sets of 3 200w Panels in ‘series’, then grouped ‘parallel’ on the +/-Buss in the roof combiner box. I’m getting my breaker size by the Short Circuit Current (ISC): Each 200W solar panel has a short circuit current of approximately 10.2A. For 9 panels, the total short circuit current would be 9 x 10.2A = 91.8A, then adding 22.5amps & rounding up to 120amp breaker/cutout.
The attachment shows two breaker/cutouts in a baby box, one 50amp between the panels & the mppt going into the PV side, one 100amp between the mppt & the lynx 1000. In place of the 100amp breaker/cutout, I have a 60amp, as this is just what was sent. The 120amp was to be installed in place of the 50amp, which is still in place. I figured the 50 had to be a mistake?? So as it sets with my array, thats a 50amp between Panels, & MPPT PV(in), & a 60amp between MPPT battery out to the LYNX. Massive Victron woes… Much appreciated…
In series the voltage is x number in series, amps stays the same as 1 panel.
In parallel the voltage remains the same as 1 panel and amps is x number in parallel.
Thank you again