Solar controllers chat

[Bossrox]

Anything to do with charge controllers

A controller is the only item left for me to get to have a complete system & been frustrating trying to find an MPPT model that can handle 60+ amps of panels input for a tolerable price. So far I've found it would be cheaper to get 3 30 amp controllers & stack them. I'm just waiting for a company I'm looking at to send me info if their units can do that. If they can then I could save hundreds of $$$ as a reputable 80-100 amp MPPT controllers start out around $500 to over a grand but 3-30 amp units would be under $300.

I kinda was looking at an Outback but after seeing some of the scathing reviews on Amazon, I think I'll pass that by. After getting a reply about stacking controllers being a dicey gamble, it now looks like I'm going to give the brand Epever in an 80 amp model a try & they start out at around $300 & a bit more with external monitors & other accessories.

Well I finally got around to tinkering around with the Epever to see what I could do with it & found after a tedious effort to get their obnoxious software to connect to my lappy, I couldn't access any charge parameters to customize it to my liking & tech support for this brand is non existent so I'll be ditching this useless contraption & now looking at a Victron 150/100 which I hear so much praise about but "ouch" on the cost. It'll be near what I paid for my inverter.

Something I've found that appears to be very important when wiring up any controller is to hook up the batteries 1st, then the panels & Victron says to block any light from the panels or do it at night.

[Bossrox]

Voltage input to an MPPT controller?

In most cases I notice that you can put 100 to 200+ volts into a controller but here's my curiosity as a newbie.... Let's say you're doing a 24 volt battery setup, it would seem to me that a controller has a heavier load task reducing that much voltage down to 24v than it would if you string the panels to just above what's needed to properly charge the batteries. Does anyone have some technical knowledge if this has any merit?

Update: Now that I have a few controllers & read some more, all controllers say using higher voltage is better which also substantially increases the controllers watt handling capability which means many more panels can be used on a single controller than if you were hooking all your panels in parallel at low voltage.

So stinging sets of panels in series to as close to but safely under the controllers max PV input voltage, is what you should be shooting for.

[Bossrox]

Got my Epever Tracer 80 amp controller & not bad but.....

The unit looks to be pretty good. I got my unit with the outboard control monitor & battery temp sensor. I hooked up today but it'll be raining all day today with no sun. My 1st surprise is without any sun, the ambient light was enough to activate it & send a charge to the batteries. I was getting a panel voltage at times of it's full 80 volt output but a very low 3 amps from my 6 panels 55 amp potential.

I haven't yet played with all it's functions but noticed it has multiple charging cycles from float to normal & even an equalization cycle with a battery temp sensor to idle it back if they get to hot. The wire terminals are good sized & sturdy, a complaint I see about so many economy controllers. So far I'm impressed.

I'll add some more info as I get familiar with it & tried to find a definitive run thru video on youtube of what it can do but found nothing but basic hooking it up so when I totally understand the things that can be done with it, I believe I'll do a video & post it here so stay tuned for that.

Update: Well after a frustrating bout with trying to figure out how to get the software to modify the charge parameters with virtually no tech support to be had, I finally got it figured out & except for 1 parameter it didn't have I thought to be real important, was no ability to program a custom equalize schedule, only the equalize duration was adjustable, however I did discover that it is preprogrammed to equalize once a month, other than that, so far, this looks to be a fairly good unit for the price but a Victron is way more advanced, more to my liking, so I got 1 & this will get set aside as a backup if the Victron goes down.

Update 2: Something happened to the Epever, went to hook it back up & it was toast. So much for that hunk of junk.

The video below is problem I had with it & the solution.

[Bossrox]

A Victron 150/100 MPPT controller was ordered & on the way

Along with it I added the front panel monitor, the bluetooth battery temp/volt sensor & the usb to pc interface cable & got it for many hundreds less than it's typically priced at but still a wallet draining good chunk of change. Even with the good deal I got, it's more than twice the price of the Epever I'll keep for a back up. It will be intresting to see what this unit is capable of, I'm already impressed with the company's literature, the seemingly good response to customer service & the advanced software parameters.

For those not familiar with Victron, the 150 means it'll handle panel voltage up to that amount & the 100 is the max amps it'll put out to charge batteries. This unit will handle up to 5800 watts of panel power & I'm just short of 4000 so it should purr along just fine with that & gives me room to expand if I want to. More test results will follow after I've toy'd around with it some.

Update: Found this out about the Victrons panel wattage ability. It's not linear, at 24 volts it will only accept 2900 watts, at 48 volts it'll take the full 5800 watts & since I'm on a 24 volt system, I can't make use of the full 3800 watts of my panels so future plans are now to move to a 48 volt system as soon as I can.

Update: Well I made my move to a new place & got my solar system back up & running now on the Victron. I luv this Victron but I discovered with my 12 320 watt panels that I was under utilizing my panel output on the Epever with an 80 amp max charge rate. With the Victron I'm using every drop my panels can crank out of 100 amps.

Update 2 I found this intresting, the Victron will crank out 100 amps at both 24 & 48 volts but 100 amps @ 48 volts is twice the power of 24 @ 100.

Well, I want to beef up my panel output but am already maxed out what I can feed into the Victron @ 24 volts but if I upgraded my panel power & stayed @ 24, it would require adding another charger but if I go to 48 volts, the Victron will accept another 2 kw of panel power so instead of spending about $700 on another charger, for another $500 I could step up to a 48 volt inverter where I'd have double the wattage & double the charge output with the same charger.

I've been wanting to get a 8kw inverter anyways so that's not to far off on the horizon.

[Bossrox]

Making use of extra solar panels when your charge controller is already maxed out

Sometime in the near future I'll be switching to a 48 volt set up but for now with 24 volts, the Victron will only handle 2900 watts of solar power. When I switch to 48 volts it will then doubles to handle 5800 watts. I have the Victron maxed out right now but til I go to 48v I've acquired 12 more solar panels beforehand that I couldn't add to the system normally but could with a solar intensity switch.

I cover the solar intensity switch in my gadgets thread but with this switch, when solar intensity falls below a set threshold, this switch will engaged them, then when the solar gets back up to par the switch will kill them until needed again. This way I can make extra amps I'd normally not be able to get in early morning, late afternoon & partly cloudy days, making smart use of the extra panels til the 48v upgrade happens.

Update: I decided to get a 2nd 100 amp charger before changing to a 48v inverter. While those switches will add extra power to the system, I could still do better on how fast I can get the batteries charged with a 2nd charger & it'll soon be time to turn on the A/C's again for which 1 charger alone can barely keep up with the demand but 2 will easily deal with that with reserve to send to the batteries.

[Bossrox]

2nd Victron 150/100 added to the system

System upgrading is going fast this month with another charger & a new more powerful inverter going in this month.

I've have double the solar panel output my Victron could handle & rigged 2 temporary solar intensity relays to kick in those extra panels during low solar & that significantly improved my charging capability but my limit stays at 100 amps which with this coming summer, when both A/C's are running, my charger would max out just running them with little to charge the batteries

Now with 200 amps, there'll be plenty to go to the batteries & most assuredly will improve my utility vs. solar stats.

[Bossrox]

Victron chargers turn out to be garbage!

My 1st 2 victrons worked about a year & gave out. They replaced those 2 & those gave out too after about a year but this time they wouldn't replace them so I gave up on that company & started using Growatt chargers & after several years now, they're working just fine & half the price of victrons with the same warranty.