Solar Fuses April 10, 2021, 11:38:32 am So I knew about the solar fuse in the DC panel which needs to be removed before cutting power to the house batteries but I wasn’t aware of a second fuse under the dash panel until recently. I noticed that, even after removing the DC panel fuse, the Blue Sky charge controller still displays amps coming in. After removing the the under dash fuse, it appears the amps are no longer displayed. What does all that mean?
Re: Solar Fuses Reply #1 – April 10, 2021, 12:37:21 pm Hi Greg; The solar fuse at the converter, connects the output of the SB3000i to the coach batteries. The fuse at the dash, installed by LD is in series with the panel(s) on the roof, is to disconnect the PV from the SB3000i. You should disconnect that fuse first. According to the solar controller manual, the battery voltage is used to reference the MPPT's output. The SB3000i was still there until you pulled the fuse at the dash, because it was daylight and the sun was powering the controller. Pulling both fuses is probably a good idea, but in the reverse order. If you are going to disconnect the house batteries, you don't really need to remove the solar fuse at the converter. RonB
Re: Solar Fuses Reply #2 – April 10, 2021, 12:46:25 pm This is the auxiliary charge circuit of the SB3000i to the chassis battery. See page 11 of the SB3000i manual. The fuse is for over current protection.Charles
Re: Solar Fuses Reply #3 – April 10, 2021, 12:54:42 pm OK, thanks. Looks like I've been pulling the wrong fuse! Ron, what do you mean when you say to pull the fuses in the reverse order?Pull the cab first, then the DC panel second? Then, reinstall the DC panel first and the cab fuse last?
Re: Solar Fuses Reply #4 – April 10, 2021, 01:09:41 pm Hi Greg; Per the manual for the SB3000i, pull the near dash fuse first to disconnect the solar panels, then pull the fuse at the converter to disconnect the solar controller completely. The last fuse, at the converter, is only necessary if you are going to work on the solar controller itself. Disconnecting the house batteries, removes power from the controller also. A bit redundant, Ron
Re: Solar Fuses Reply #6 – April 10, 2021, 06:51:56 pm Thanks Charles; Greg, you can leave that fuse near the dash alone. it doesn't go to the roof panels. For that matter why are you playing with that fuse at the converter? That is power from the SB3000i into the batteries. Leave that one alone too. If you really think you need to disconnect the house batteries, use the LD disconnect switch, and leave the rest alone. I never turn off my house batteries, or anything else. Only occasionally when I'm working on it. RonB
Re: Solar Fuses Reply #7 – April 12, 2021, 11:30:42 am Quote from: Charles & Donna - April 10, 2021, 12:46:25 pmThis is the auxiliary charge circuit of the SB3000i to the chassis battery. See page 11 of the SB3000i manual. The fuse is for over current protection.Thanks, Charles. I’ve been reading in the manuals and am trying to learn all the ins and outs of the solar system and how it interacts with the rest of the 12V system.Does anyone know if LD installed a breaker to isolate the solar panels, or is pulling the fuses the only way to do it?
Re: Solar Fuses Reply #8 – April 12, 2021, 10:43:51 pm Quote from: HiLola - April 12, 2021, 11:30:42 amThanks, Charles. I’ve been reading in the manuals and am trying to learn all the ins and outs of the solar system and how it interacts with the rest of the 12V system.Does anyone know if LD installed a breaker to isolate the solar panels, or is pulling the fuses the only way to do it?Actually you might just do what I did, and have a disconnect switch installed to turn off the solar panels, so that you just flip the switch (mine is bright yellow, located on the roof of the battery box). It's much simpler.Kristin 1 Likes