Rogue MPT-3024 in Remote Cabin

Panamapat · October 2009

I purchased a unit and installed it in our remote off-grid cabin in the mountains of Colorado. The unit has 4 panels combined rating of 290 watts wired in parallel for a 12 volt system charging 4-220 amp-hour 6 volt batteries (combined series/parallel wired for 440 amp-hour total at 12 volt).

The solar system powers a few 12 volt LED lights and 12 volt CFL's, a 120 volt 1000 watt inverter for 120 volt CFL lights and small wall warts for recharging battery tools and a larger 2000/4000 watt inverter for occasional higher 120 volt loads. We use the cabin on weekends and disconnect loads when we are gone, so the solar charge controller does most of its work while we are there and right after we leave to restore battery charge levels.

So far, I've been quite pleased with the charge controller. The data logs show that I'm able to routinely get a real 250-300 watts from the solar panels with a few peak readings over 300 watts (318 watts peak).

I've uploaded the excel spreadsheet were I've captured some of the data logs at the following link:
http://home.comcast.net/~panama.pat/Cabin/CabinSolarInfo.htm
The Data Log tab has the raw data while Watthours and PeakWatts tabs display in chart format.

The Rogue appears well made, and remains very cool when full sunlight on panels results in 20+ amp charge rates. With winter approaching, I'm hopeful the colder panels will perform even better.

The Rogue manual is well written and Marc (owner) has also been very responsive to customer inquiries.

I'll continue to post as I continue to learn and test the performance of the Rogue.

Pat

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

You may not be so happy with this system in a couple of years: it's a bit short on panels for 440 A/hrs of battery. The charge rate may be a bit on the low side, leading to early sulphation. If it were me, I'd double the PV's.

lorelec · October 2009

Re: Rogue MPT-3024 in Remote Cabin

I believe Pat has another 145 watts running through another controller to the same battery bank. According to the data, his batteries are reaching full nearly every day, so I think more PV would probably be a waste of money, especially considering that the system sees only occasional loading during the summer and virtually no loading during the winter.

Marc

icarus · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Sounds like a nearly identical setup as mine. With 300 watts of Pv, into ~450 ah (12vdc) of T-105's I see about 15 amps on a mid summer day, climbing to nearly 20 with edge of cloud fall days. Every once in a while I get over twenty in mid winter. It sounds like the Rouge controller is a bit better maximizing the Pv than the Bluesky 2512 that I run.

As for Marc's (CaribooCoot) comment, I amp perfectly happy with my set up. If I could double the number of Pv amps that would be great, but since we get fully charged by ~noon I have no reason to complain. I know a lot of folks make a big issue of not being able to eq with Pv. My answer is,, I'll eq with the genny and the Pv on a clear day. Truth be told, I don't eq very often, as the SG is always the same in every cell, and after 3 hours of eq it hasn't risen very much.

Tony

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Another 145 Watts would make a significant difference. I always like to shoot for that 10% charge rate just to be on the safe side.

Tony - You are a one-man testimonial to (among other things) the quality of Trojan batteries!

Me, I use so much power a practically 'meld down' my batteries daily. Got plans though. Better batteries to start with (hmm, maybe Trojan T105). More insolation too (cut down trees *sigh*). And yes, more panels. You wouldn't believe the way the sun shifts from Summer to Winter up here!

icarus · October 2009

Re: Rogue MPT-3024 in Remote Cabin

I'm not sure a testimony to Trojan, but more to the fact that I have always been "the power nazi"! Just ask my wife. Now that we are in the new place that was designed from the ground up to be efficient, I find myself using more and more power! I strive to keep output to ~50 ah/day. (that is measured in the morning) We probably use closer to 100 ah/day now, but are left with a deficit of ~50 most days. Given that, panels get in full sun by ~9 am in the winter, and stay that way until about 3 pm, giving me ~12-18 amps depending on the puffy clouds, so the charger begins to power down shortly after lunch, so we plug in the lap tops, the drill batteries, turn on the water pump if we haven't needed it. By 5pm the radio and the kitchen light(s) come on along with the ceiling fans.

Those that have never lived in the north have no idea how high the sun gets in the summer,, nor how low it gets in the winter. Winter time, the sun comes up about 8.30 and it is down by 4.

Tony

Panamapat · October 2009

Re: Rogue MPT-3024 in Remote Cabin

I do have an extra set of panels (145 watts) on a Mark/20 charge controller wired to the same battery bank. At some point, I thought I'd rewire those panels through the Rogue, but have not done so yet. The truth is the other panels are not putting out anywhere near 145 watts because 90 watts of it are the amorphous Harbor Freight kit panels and an Arco 55 watt panel. I get around 6-7 amps max.

We probably consume 40-50 amp hours each 24 hours when we are at the cabin and typically the batteries are recharged within a day of when we have departed.

Tony - I can relate to the lack of sun. The location of my panels is not ideal given extremely dense and mature lodgepole pine forest and the cabin being located in a valley that is fairly shielded from the sun much of the winter. At some point we want to trim trees to allow for more sun, but have not done so yet. Watt-hour production drops dramatically (see charts) from June to Sep where June highs were 1000 watt-hours, while September dropped to half that amount. When I as there a couple of weeks ago, the panels didn't get full sun until around 10 and its behind the trees by 2-3. Picture below is from our March trip. You can see the one 55 watt panel high on a pole that set vertically during winter to assure I get some sun to the battery bank.

Regarding sulfation concerns, I've been worried about about it as I've not been regularly equalizing the batteries. The Rogue has the equalize feature, but I have not used it as its usually busy recharging batteries when I'm there. (Marc - perhaps a feature that allow a programmable delayed start?) I also have a portable generator with a charger that has equalize function that I should use at least a few times a year.

Lots more to learn but so far so good.

Pat

niel · October 2009

Re: Rogue MPT-3024 in Remote Cabin

i wonder if you are replacing what you are using every day. you may want to get a meter like a tri metric to tally up the ah you get.

Panamapat · October 2009

Re: Rogue MPT-3024 in Remote Cabin

niel wrote: »

i wonder if you are replacing what you are using every day. you may want to get a meter like a tri metric to tally up the ah you get.

I've thought often about getting a trimeteric and some day I'm hopeful I will. They look really useful.

_OS_ · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Cariboocoot wrote: »

You may not be so happy with this system in a couple of years: it's a bit short on panels for 440 A/hrs of battery. The charge rate may be a bit on the low side, leading to early sulphation. If it were me, I'd double the PV's.

I have 600 Ah batteries and two 80W panels and have had no problems. In two years I have used the generator to charge the batteries only two times. But I only use the system a weekend or two each month.

OS

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

_OS_ wrote: »

I have 600 Ah batteries and two 80W panels and have had no problems. In two years I have used the generator to charge the batteries only two times. But I only use the system a weekend or two each month.

OS

I can't see that working long-term. 160 Watts? Your peak charge current being 13 Amps or so? That's way below recommended 5% minimum for 600 A/hrs.

There's two factors for properly recharging batteries. On is 'replacing' the Amp/hrs you use each day. That's fairly easy to achieve because it is only dependent on the panels putting out the same total Watt/hours that you consume (plus a bit for losses). Insufficient panels for this will show up right away, as you won't achieve 'full charge' each day.

The other is to achieve a charge rate of sufficient current to combat the sulphation problem. That is a problem that won't show up for years, because as the batteries slowly lose capacity due to the ever-growing coating on the plates they require less to bring them up to full Voltage.

I could be wrong. The fire went out last night and the temperature was -5 (27 F) outside. I'm freezing my fingers off!

Probably my infamous brain has quit working too.

Regarding insolation, I have the opposite problem of most people. The way my panels are oriented, they do worse in Summer than Spring/Fall. Winter is abysmal because the day is only 6 hours long anyway.

_OS_ · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Cariboocoot wrote: »

I can't see that working long-term. 160 Watts? Your peak charge current being 13 Amps or so? That's way below recommended 5% minimum for 600 A/hrs.

There's two factors for properly recharging batteries. On is 'replacing' the Amp/hrs you use each day. That's fairly easy to achieve because it is only dependent on the panels putting out the same total Watt/hours that you consume (plus a bit for losses). Insufficient panels for this will show up right away, as you won't achieve 'full charge' each day.

The other is to achieve a charge rate of sufficient current to combat the sulphation problem. That is a problem that won't show up for years, because as the batteries slowly lose capacity due to the ever-growing coating on the plates they require less to bring them up to full Voltage.

Thanks for the explanation. Is sulphation a problem with AGM batteries as well (I have the largest SunXtender batteries)? Anyway, I will start using my generator more often from now on.

Ole

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

_OS_ wrote: »

Thanks for the explanation. Is sulphation a problem with AGM batteries as well (I have the largest SunXtender batteries)? Anyway, I will start using my generator more often from now on.

Ole

Sulphation is a problem with all lead-acid types, as far as I know. AGM's are more 'picky' about charge Voltages, and it isn't recommended that they be Equalized (except in a few cases, and then it's 'soft' EQ). This is because they don't have a lot of acid in them; it's all sopped up in the Glass Mat. That's why they're also called 'starved electrolyte'. It's easy to over-charge them and 'boil them dry'. After which, since they're sealed, you can't replace the liquid. But they do have their advantages, which strangely are the same root as the disadvantages: they're sealed! No having to check fluid levels and top-up. Properly charged, they're less of a headache and less likely to freeze if under-charged.

BTW, never EQ a Gel battery: they can explode. Had it happen once (not EQing - charge Voltage was wrong).

niel · October 2009

Re: Rogue MPT-3024 in Remote Cabin

marc,
explode? yikes, that's not good.

correct me if you feel i'm wrong, but gel batteries are vrla types and the explosiveness should've been allowed to vent rather than explode so i believe the valves on it were either none existent or defective.:grr

os,
i thought i remembered one of the guys saying sunxtenders are claimed to not sulfate, but i would go on the assumption that any battery can. i agree that your charge rate may be a bit low as 13a/510ah=2.55%. i would think about a 3% rate with no loads on it would be about the minimum one would want that is allowed to reach a full charge. the lower %s cause longer times until a full charge is reached and add to that any loads before reaching a full charge can create a deficit charge and never reach full which causes sulfation to occur too.
on the plus side the agms are more efficient at charging, but i still don't recommend rates as low as yours.

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

niel wrote: »

marc,
explode? yikes, that's not good. correct me if you feel i'm wrong, but gel batteries are vrla types and the explosiveness should've been allowed to vent rather than explode so i believe the valves on it were either none existent or defective.:grr

That could be. It was a "back-up" battery for a large Blaupunkt multi-band radio. Built-in charging circuit. The case burst and there was gunk everywhere. Evidently something failed in the circuit: V+ at the battery terminals afterwards was nearly double the battery's Voltage. That's about all I remember from that incident, other than having to toss the radio due to damage. I liked that radio too.

westbranch · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Ole, I do not know if you have seen the string on Absolyte AGMs and the reference to 'CatVent's'... here http://forum.solar-electric.com/showthread.php?t=4624&highlight=AGM+catalyst

If not there is good reading there, plus links, on the nature of the internal processes of AGMs and how the chemistry works, or is supposed to work..

Eric

n3qik · October 2009

Re: Rogue MPT-3024 in Remote Cabin

niel wrote: »

marc,
explode? yikes, that's not good. correct me if you feel i'm wrong, but gel batteries are vrla types and the explosiveness should've been allowed to vent rather than explode so i believe the valves on it were either none existent or defective.:grr

Cariboocoot wrote: »

That could be. It was a "back-up" battery for a large Blaupunkt multi-band radio. Built-in charging circuit. The case burst and there was gunk everywhere. Evidently something failed in the circuit: V+ at the battery terminals afterwards was nearly double the battery's Voltage. That's about all I remember from that incident, other than having to toss the radio due to damage. I liked that radio too.

Yep, those gel batteries used in UPS backups are sealed. At work we have 35 users with a UPS. I get about 3 a year that swell/burst. Our field equipment have two 12v 17AH batteries, a tech replaced a set that swelled to twice their size and melted together.

BB. · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Ken,

Yikes--a 10% per year failure rate? Or it is less because the customers have more than 1 UPS per?

What is causing the failures? Electronics (charger bad, improperly designed)? Batteries (cell shorts)? Or just a tough application (small batteries, heavy loads)? Etc.?

-Bill

n3qik · October 2009

Re: Rogue MPT-3024 in Remote Cabin

The failures are due to age. I get about 3 years out of a battery. But the cost of a battery is cheap insurance against any data/hardware losses.

RandomJoe · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Back on the low charge rates, I'm at the low end - 540W in panels, 660AH or so in batteries (6 T105s wired for 12V). That's about 5%. I easily replace what I use each day, and the system makes it to absorption, then float. The batteries seem fine.

However, on occasion I need to use the AC charger (had a LOT of cloudy weather recently) and wow what a difference! It's a 55A Iota (that gets closer to 60A during bulk) with the smart charge board in it. The thing will go to absorb, and spend *considerably* longer there than the solar charge controller does - the current stays high, instead of tapering like it does on the CC. I left the thing running overnight one night, and it did finally get back to float, with a final current draw much like the solar system sees in the afternoon when floating, but had put in a Whole Lot More amp-hours than the solar system ever thought about!

I have decided getting the higher amperage charge current is a good thing - use it as my load when test-running the generator each month (although that's only an hour) and plug it into the wall whenever the storms move in just to be sure the bank is full in case the power goes out. (Although all the outages I've had since I put it in were on perfectly calm, storm-free days! :roll: )

Still waffling on doubling the panels. NAWS still has that nice price on the ones I used (although they've already slightly changed, so aren't identical darn it) but... Hm...

icarus · October 2009

Re: Rogue MPT-3024 in Remote Cabin

RJ,

The question would be, just because you put more AH into the batteries, does that mean you have that many more to draw out before you are at a similar DoD? (SoC)?

I'm not arguing with you, as I am asking a legitimate question. My CC goes to float after two hours of absorb (very rare) and the Tri-metric reveals that I have put as many ah in as we have taken out. Even in absorb the CC drops the current to ~5 amps for abosorb. If I run the genny for some reason, the Xantrex TC 20 will then charge at ~10 amps for several hours. In fact I have never seen it go to float. (BTS installed on both units and my batteries tend to be quite cool, even cold).

The question is should I consider changing the parameters of the CC, (or the Xantrex TC)? Leaving the CC longer in bulk, or longer in absorb?

Tony

RandomJoe · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Icarus, I'm not really sure! The battery monitor (Outback's FlexNet DC) will indicate 100% charged for quite a while before the Iota gets done and drops back to float. On the other hand, I've left the system solar-only for a few months straight earlier in the summer and certainly never had any indications I was running short with the batteries. The FN-DC indicates 100% each day with solar as well.

Best test, of course, would be to see what the SG is doing, but I've been lazy and not checked that when I should. Need to get more in the habit.

The FN-DC usually indicates even with solar charging that I put in more than I remove. When I run the Iota, it shows a LOT more in than was taken out!

Part of this *may* be the FM-80 has a time limit on absorption phase, after which it drops back ready or not. It appears to me the Iota does not do this.

Although I'm a little confused by just how the Iota works in the first place. While in bulk, the voltage gradually rises to 14.1-14.2V, and the current starts to taper off. Good so far. But a short while later - and I've not done it enough times to really figure this out, it's an hour or so - the voltage drops to 13.8. I *thought* this was its float setting, but no - as the current continues to fall, the voltage *climbs* again, to 14.0 and holds there a LONG time. Until this past week when I accidentally left it on all night, I normally shut it down in that state. This past week, when I got out there in the morning, it had gone ahead and dropped down to 13.2V and was holding the usual float settings and currents I'm used to on the FM-80.

It's all been quite the learning experience, and my system isn't even a year old (and still growing!) so I still have a long way to go! :cool:

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Now I'm wondering what criteria the Iota uses to determine absorb time. Anyone know?
(Iota manual: http://www.iotaengineering.com/pplib/IQ4manual.pdf Interesting reading on its charge functions.)

If the FM80 is like the MX60, then min and max absorb times can be programmed (from 1 to 4 hours with a 10 minute minimum difference). Normally, the MX determines absorb time by counting up from when the bulk charging starts to when absorb voltage is reached (up to the maximum). I'm not sure how good that number is. It seems to me that more Amp/hrs of battery would need longer absorb time, regardless of how fast they charge up to absorb voltage.

There's been discussion in another thread about Surrette's recommendation to set Float voltage to the same as Absorb, and reduce it if too much water consumption is noticed.

This may be related to that bugabear about replacing the amp/hrs vs. having enough charge current to combat sulphation.

The effects are more likely to show up in a large (+400 Amp/hrs?) bank than a small one.

I've noticed an improvement in my battery bank's performance from increasing the Float voltage above the recommended settings.

mikeo · October 2009

Re: Rogue MPT-3024 in Remote Cabin

I've noticed an improvement in my battery bank's performance from increasing the Float voltage above the recommended settings.

I don't know if this comment is relevant but the DECA person I talked to recommended 28.2 volts for my traction battery that is rated 940 amp hours at the 20 hour rate. That is quite a bit higher then I have read for most other 24 volt nominal batteries.

Cariboocoot · October 2009

Re: Rogue MPT-3024 in Remote Cabin

mikeo wrote: »

I don't know if this comment is relevant but the DECA person I talked to recommended 28.2 volts for my traction battery that is rated 940 amp hours at the 20 hour rate. That is quite a bit higher then I have read for most other 24 volt nominal batteries.

Likewise. The recommended rate for a 24V system is 25.6 - 26.4. I have mine set to float at 27.6, based on the quite arbitrary and unscientific rationale that automotive systems are meant to 'float', as it were, at 13.8 - * 2 = 27.6.

Right now I'm too chicken to push it any higher.

And I apologize to the OP for being mainly responsible for this thread running off into a totally different direction to the point where it no longer fits the category it was originally posted under.

Maybe we need a new thread to discuss real-world charging vs. recommended rates?

blackswan555 · October 2009

Re: Rogue MPT-3024 in Remote Cabin

RandomJoe wrote: »

Icarus, I'm not really sure! The battery monitor (Outback's FlexNet DC) will indicate 100% charged for quite a while before the Iota gets done and drops back to float. On the other hand, I've left the system solar-only for a few months straight earlier in the summer and certainly never had any indications I was running short with the batteries. The FN-DC indicates 100% each day with solar as well.

Best test, of course, would be to see what the SG is doing, but I've been lazy and not checked that when I should. Need to get more in the habit.

The FN-DC usually indicates even with solar charging that I put in more than I remove. When I run the Iota, it shows a LOT more in than was taken out!

Part of this *may* be the FM-80 has a time limit on absorption phase, after which it drops back ready or not. It appears to me the Iota does not do this.

Although I'm a little confused by just how the Iota works in the first place. While in bulk, the voltage gradually rises to 14.1-14.2V, and the current starts to taper off. Good so far. But a short while later - and I've not done it enough times to really figure this out, it's an hour or so - the voltage drops to 13.8. I *thought* this was its float setting, but no - as the current continues to fall, the voltage *climbs* again, to 14.0 and holds there a LONG time. Until this past week when I accidentally left it on all night, I normally shut it down in that state. This past week, when I got out there in the morning, it had gone ahead and dropped down to 13.2V and was holding the usual float settings and currents I'm used to on the FM-80.

It's all been quite the learning experience, and my system isn't even a year old (and still growing!) so I still have a long way to go! :cool:

Be a little careful with the FNDC and it`s indicated SOC, If it was not commissioned to the letter of the book, It will not be accurate, But it does not sound like it is working correctly anyway,

Commissioning it correctly :
It MUST be installed when batteries are fully charged
It must do at least one complete cycle before you let it drive,
I was recommended by Outback to not use SOC charging control until I had cross referenced the SG`s vs the SOC indicated, Adjusted th BCF setting to compensate, and was happy with it over a few weeks, (set SOC start and stop to 0% to disable that part of it)

The other parameters that "make it work"

Battery end of charge amps, The charge amps the bats pull when fully charged, 2.5% is a good place to start, but cross referencing it against your SG`s is the best, will be higher on old bats.
Bat voltage, Set it to 0.2v lower than your absorb on 12v + 24 v, 0.4v lower on 48v,
Time met,(2 mins for me) Time the above settings have to be reached and held for, when all met, FNDC decides Bat`s are full, Stops charge/go`s to float and also resets SOC reading to 100%

Have a good one
Tim

icarus · October 2009

Re: Rogue MPT-3024 in Remote Cabin

The SG in my batteries gets to ~1.265 even when either the CC or the TC 20 are in bulk. It may inch a tiny bit higher ~1.27 but never higher even when the CC goes into absorb and then to float.

It seems to me that adding additional ah to the battery beyond that point is just waste, (aside from the mixing function of "boiling" the electrolite).

I think the long and short of all of it is that battery use/charging is as much art as science, with a bit of black magic thrown it. I guess if one is happy with one's battery performance, then I guess that counts.

Tony

RandomJoe · October 2009

Re: Rogue MPT-3024 in Remote Cabin

blackswan555 wrote: »

Be a little careful with the FNDC and it`s indicated SOC, If it was not commissioned to the letter of the book, It will not be accurate, But it does not sound like it is working correctly anyway,

As far as I know, the FNDC isn't "running" anything anyway - I just use it as a fuel gauge for me to know where things are at. The CC doesn't seem to be affected in any way by what the FNDC indicates, and just operates off its own internal sensors and settings. But perhaps not - I never did get a very good feel for just what level of integration occurs between the two.

I did set it up per the instructions - batteries full charge, let it go a cycle (indeed, it's gone MANY cycles now - been running since May or so), so forth. As I said before, I've been lazy and haven't made any systematic comparisons against SG, but then I've not really had anything suggest I needed to. (Thus the "lazy"!

)

I even got to do the setup twice - my first one had old firmware with the "end of the month" bug where it reset the SOC.

I have wondered about the accuracy of the shunts in my situation. My loads are quite low, as a general rule I'm running 3-5A. That's just barely 1% of the shunt's range! (Would be nice to be able to use something other than a 500A shunt.) I suppose it's possible for shunts to have incredibly good accuracy numbers, what are typical tolerances? With the various sensing devices I use at work, 2-3% is "good" and 1% is a precision (and expensive) device. I start wondering if perhaps my loads aren't *quite* what the meter indicates. If I'm actually pulling another amp or two more, over the course of 24 hrs that is going to add up.

I agree with Icarus, this often gives the feel of art / magic as much as science!

Guess that's why I like playing with it too! :cool:

BB. · October 2009

Re: Rogue MPT-3024 in Remote Cabin

Deltec 100 amp, 100 millivolt current shunt
AC or DC - common item for use with many battery monitors and amp meters ~$24 + shipping

And there should be smaller ones available--if needed.

Check what "shunt range" is supported in the configuration interface...

-Bill

RandomJoe · October 2009

Re: Rogue MPT-3024 in Remote Cabin

The problem is (as far as I can tell) there's no way to get the FNDC to use anything other than a 500A shunt!

rguruprasath · March 2010

Re: Rogue MPT-3024 in Remote Cabin

I'm so new to the solar world and I have a 70 watt panel. Would like to understand about the "low charge rates" explained in this thread. Can someone explain it to further.

Rogue MPT-3024 in Remote Cabin

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