Cat-Sam
New Member
I have a 2 x 120w install on my RV, 4mm cables and wired to a Victron MPPT 100 / 50. I wanted to upgrade the system and learning that my limitation seemed to be the factory installed 6g (4mm) cables i realised that if adding any additional panels that i would need to do so in series (like the existing 2 already installed. Added 2 more panels of 100w each today, all connected up and checked, seemed OK. Took the RV out of the barn to check that i was harvesting some watts and checked on the Victron app and immediately got an over voltage warning (it was running at 118v), drove the RV back in so they system ran for max 3mins. After that i disconnected everything just to make sure, then next step check on here with someone that has more PV knowledge than me (not hard..).
The 120w panels are rated at 20.5v and the 100w panels are rated at 20.4v so I’m a bit lost as to why they output over the max 110v of the MPPT ? It was cold today, around 5 degrees C.
I‘m assuming i fried the MPPT but will anything else likely be damaged ? Then i assume i need to upgrade the MPPT to a larger unit, any advice ? A straight swap out would be the Victron 150/35 i assume.
Many thanks and happy sun harvesting
The 120w panels are rated at 20.5v and the 100w panels are rated at 20.4v so I’m a bit lost as to why they output over the max 110v of the MPPT ? It was cold today, around 5 degrees C.
I‘m assuming i fried the MPPT but will anything else likely be damaged ? Then i assume i need to upgrade the MPPT to a larger unit, any advice ? A straight swap out would be the Victron 150/35 i assume.
Many thanks and happy sun harvesting
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