MPPT Solar Controller

[sailorboy1]

Looks that my solar controller may have bit the dust. So looking for suggestions for a replacement MPPT controller for 60 amps. I will of course look online myself and research any good sounding suggestion.

[Discovery 15797]

I'm very satisfied with my Victron controllers w/Bluetooth.

[stillbuilding]

My Victron after 6 months went open circuit and destroyed all six of my 100 ah gels. Not happy.

Originally Posted by Discovery 15797

I'm very satisfied with my Victron controllers w/Bluetooth.

[misfits]

Midnight Kid. Easy to operate & has a viewable menu. Not sure it can handle 60 amps thou.

[Mike OReilly]

My only experience is with the Victron line (100/30). Has worked flawlessly since the day I installed it.



What one was yours, and how did it die?

[noelex 77]

If you want a single controller for this type of current, the Midnite range is probably the best.

I think from memory, that you had an Outback controller. If so, these are still excellent and it may be simpler just to replace like with like, especially if you have any of the accessories such as the Mate. The Outback controllers can be repaired. Often the capacitors go bad in these MPPT controllers and this is not a difficult fix.

The other option to consider is multiple smaller controllers. This provides some redundancy that is valuable since MPPT controllers are not very reliable (I did not need to mention that, did I ). However, this will need some rewiring, which can sometimes be very involved. If you do decide to install multiple controllers the Victron models are hard to beat if you want relatively small units.

[sailorboy1]

I have an Outback FlexMax 60. It is almost 8 years old and has been great till now. It isn’t passing any current and is definitely the controller. Im waiting to hear back from Outback.

I’m going to stay with one panel and want one that fits the spot i already am using. In the end I probably will get another FlexMax 60 as there were reasons I chose it back in past. But figured it was worth checking into for others.

[Rubicon King]

Midnight solar is very good and what I installed. very simple MPPT. I used the 250 Classic... VERY satisfied

[sailorboy1]

I looked at the Midnite controllers. I will assume they are excellent, but wether they are 50+% cost better than the Outback is questionable.

But note that did look it up for consideration.

[thomm225]

Originally Posted by stillbuilding

My Victron after 6 months went open circuit and destroyed all six of my 100 ah gels. Not happy.

An open circuit isn't going to destroy anything. Sorry. Not sure who told you that.

[skipgundlach]

Thanks to Wotname for referring this thread.

I have a BlueSky 60A controller with which I'm well pleased, despite having had a failure on the original after 13 or so years.

I had a refurb available to me from my original installation, so bought it and installed it, keeping the info-screen front panel (the refurb didn't have that extra-cost feature despite it being the same unit otherwise).

I sent off my original for analysis, and as expected, "she's dead, Jim" was the response. However, in the meantime, I'd discovered that their tech guy, Ryan Gurin, was not only very thorough, but available nearly any time, some of our correspondence having happened over weekends.

My unit (no longer available) is the SolarBoost 6024; it will handle 140V input and 60A output.

Based on my interaction there, I'd seriously consider another Blue Sky unit if this one goes TU...

[sailorboy1]

Thanks guys. I spoke with an Outback tech who didn't know what to do or how to fix the problem saying they would check within the group and get back to me. No one of course got back to me.

I found a good deal on Amazon for a new/opened FlexMax 60 so ordered it

[sailorboy1]

Here it is, the best opening ever provided for trolls.

Installed the new controller (exact replacement) and it had the same problem. This started a slow piece by piece review and inspection and isolation of every wire and connection in the system. On the second pass of connecting and disconnecting stuff i found it, a burned up MC4 connection on the GROUND common line at the panels (that worked on one isolation go through but didn't the next go).

Since there was voltage at the controller from the panel I never suspected a wire problem. My thinking was that if there was voltage there was a connection that would carry at least some current (the problem was that no current was flowing through the controller). The Outback tech also thought the same.

[Mike OReilly]

Ouch... what would have caused that?

[Jon Hacking]

Originally Posted by noelex 77

... The other option to consider is multiple smaller controllers. This provides some redundancy that is valuable since MPPT controllers are not very reliable. However, this will need some rewiring, which can sometimes be very involved. If you do decide to install multiple controllers the Victron models are hard to beat if you want relatively small units.

I'm with Noelex on this. We just upgraded our array from 8x120W (36-cell so 12v nominal, wired in 4 parallel strings of 24v) panels running through a single Blue Sky SB50, to 3x400W (72-cell, so 24v nominal) panels each feeding its own MPPT. The SB50 (from 2001!) is handling one of the panels, while the other 2 are going through their own SRNE ML2430 MPPTs, since that's what the dealer in Davao (Philippines) had available ($140 each, including remote displays).

This setup is sub-optimal in a few ways. The ML2430s require a special cable or Bluetooth adapter to program them, & none of the MPPTs are talking to each other, so to get net current produced by the whole array, I have to do some mental arithmetic. But it's cheap, simple, & it performs well while giving me a bit of redundancy (the SB50 can almost handle 2 panels).

If you're trying to control 60A, you've got multiple panels. Running them in parallel means that if one gets even a little shaded, it won't be able to reach the MPPV of the other strings, so it will simply drop out of production. But if each series string of panels is feeding its own MPPT, then such a drop in voltage can still contribute meaningful current to your batteries. And multiple small MPPTs is often cheaper than a single large one (certainly was in my case).

I started a thread about finding the "best" MPPT a while ago. It seemed that Victron had the most integrated approach, but you needed to buy multiple units & get them all talking Bluetooth together. While RF signaling minimizes wires, my (very limited) experience with bluetooth is that it's not reliable enough for prime-time yet.

But whatever you get, if you're charging lead-acid batteries (FLA, sealed, Gel, or AGM) then you REALLY need to get an MPPT that measures current into the batteries (usually via your amp-hour shunt). I'm appalled at how many charging systems don't have this ability, as it's critical to knowing the state of charge of the batteries, & when to switch down to Float. Many just use timing algorithms, which are hopeless on a cloudy day. Even worse, if you leave the dock with fully charged batteries (or you've been motoring all night) then time-based algorithms will try to over-charge your batteries for 2 hours! I killed a $3,000 bank of Sonnenscheim Gels in about an hour by accidentally over-charging them. Get a solution that knows the state of charge of the batteries by measuring the current into them.