I recently added another Renogy RSP200D solar panel for total of four in series in front of my 100/50 Smart Solar Charger. I haven’t run into any overvoltage issues with a high of 95V in the last few weeks, however I have seen the controller clip when hitting 49.7 to 50.3 amps. I thought it might just regulate it, but it seems to shut down for a minute. Not a huge issue as it only seems to last 60-90 seconds or so. Am I damaging the unit? Using my Fluke IR Thermometer I’m seeing about 136 F on the rear cooling fins. Definitely warm, but not outrageous hot either. My plan to reduce clipping, increase efficiency and lower the controller temperature is to get a Victron Energy MultiPlus-II 24/5000/120-95 120V - 24V Inverter and re-wire my 8 100Ah batteries for two groups of 4 in parallel, then in series for 400Ah @ 24V. Obviously I’ll have reprogram the charge controller for 24V output. Does this make sense? Eventually I’ll add some dedicated 24V batteries and add another inverter for two 120V legs so I can run my air compressor and welder (30A draw)… The other option would be to rewire the batteries for 48V @ 200Ah and just get the 48V version of the Multiplus but I’d have to buy a 48V compatible controller. Which would you do and what makes the most sense from an efficiency and expandability view? Edit: I pulled the data sheet and according to notes 1a,b) and 2) damage will occur if over amping the input from the solar panels, but no mention of overvolt? Interesting… Not that I would try it. I’m maxed out as it is..
1a) If more PV power is connected, the controller will limit input power.
1b) The PV voltage must exceed Vbat + 5 V for the controller to start.
Thereafter the minimum PV voltage is Vbat + 1 V.
2) A PV array with a higher short circuit current may damage the controller.
I see your other thread where you mentioned the risks already with the Voc. Clipping is normal and shouldn’t shutdown the controller. I would be looking at cables, fuses and connections.
Running the MPPT that close to its max Voc stays a bit risky imo.
Clipping is normal for over current, its not normal to shat the scc down everytime.
I ran 4 x 500W panels on a 100/50 into a 24v system, it clipped the amps the whole day but I got 50 Amps out constantly (almost)
the most important factor is the VOC, do not exceed EVER!
The scc will “pull” the max amps from the panel upto the max amps of the scc, it cannot “pull” more amps from the panels into the scc, that is the moment clipping happens
I have a SmartSolar 100/50 that also exhibits the same behavior. MPPT would shutdown or throttle for a short while when 50 amps output was hit, even when PV input voltage was much lower than max 100V and input current lower than 50 amps. MPPT was not hot.
I was able to stop the shutdown/throttling behavior by setting the max charge current to 46 amps. The MPPT could then charge at 46 amps continously even though there was sufficient PV to have full 50 amps output charge current.
If I can reply to all.
1: After digging further into the MPPT logs I saw a high of 95.7V when the battery bank was fully charged. I’m really right on the edge and the temps in the morning were around 0 to 2c.
2: I totally agree with what @jcharlebois posted above. I pulled my charge current to 48 amps and I saw no dips to Zero.
3: However, I still ordered a 5000VA/24V Multiplus ii. Not because I have money to throw away, but because I could eventually expand to run my air compressor and welder with enough solar panels to recover.
4: I plan on replacing my 100/50 with a couple of 150/70’s in syncronis, solar is addicting.
5: My Giandel 2200W pure sine has been amazing.. We’re talking on it right now, lol. I can run my table saw for a few minutes, my drill press for a few minutes, not too shabby
