Just starting to investigate this question Pwm-Mppt
Re: Just starting to investigate this question Pwm-Mppt
The bogart system is 2 seperate parts not all in one,the battery monitor essentially controls the controller...you have to plug in an exact manufacturer figure for absorption voltage because bingo it uses two ways to determine 100 percent charge..the first being as you say when the amount of amps the batteries are absorbing (you also have to input the size of your battery bank amp hours)falls below the set percentage I think it is .5..... It also looks at the amps that were taken out of the battery bank and how many were replaced...then for each battery manufacture they suggest a different tiny overcharge...so for example you used 20 amps...it counts the amps replaced (via the shunt)and replaces them with 20.5 or 21 amps or whatever you plug in as the manufactures recommended percentage...... I think I follow your narrative but...I don't have any loads greater than 3-4 amps...and dont run heavy loads,and don't truly know how my monitor and controller would react to the situation you describe...I appreciate your addition of algorithm explaination,but if I am correct they are are like sophisticated mathematical guesses as to where your battery is,if I understand correctly the battery monitor and shunt have more information and can make a better assessment as to which stage is appropriate....(my Beef with the Progressive dynamics charger is that it's absorption and bulk stage voltages don't jive with my battery...so whatever it guesses with whatever numbers,it is not by nature optimum...It may er on the side of caution and throw itself into float,but really.....) My original point and the reason I find your post Germaine is that,it is perhaps more important than worrying about the amps you may be losing by using pwm (and not needing)to make sure your system is setup to fully recharge your batteries on a regular basis by accurately adjusting the voltages,according to manufacturer,temperature and not egregiously overcharging them.It may be (just a hypothesis) we don't need a system that harvests 100% efficient,but rather a system that uses what it does harvest(let's say 75% with a flat pwm) correctly.Hope that makes sense.Rooney
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Willywalderbeast
- Posts: 232
- Joined: July 17th, 2016, 5:00 pm
Re: Just starting to investigate this question Pwm-Mppt
I must be over complicating this solar install haha. I've read this thread over n over and I can't pull the trigger on a MPPT controller. I have two Renogy 100w Eclipse panels that I will be mounting on the left side of the rv roof in parallel behind my newly installed king antenna. The positive to this I see is that The panels will be on the same side as the battery compartment. Essentially all I have is a short run straight down to the battery compartment where somewhere in between will be the controller.
I almost pulled the trigger on the victron MPPT 100/30 but then hesitated due to it not having the ability to run a wire to the battery compartment to adjust for the temp.
So without diving into the information that was already covered, if you were in my situation what controller would you purchase thanks!
I almost pulled the trigger on the victron MPPT 100/30 but then hesitated due to it not having the ability to run a wire to the battery compartment to adjust for the temp.
So without diving into the information that was already covered, if you were in my situation what controller would you purchase thanks!
Re: Just starting to investigate this question Pwm-Mppt
Well, a couple of questions:
Are you likely to be adding more panels any time soon?
Do you think you may want to add ground panels?
For the two Eclipse panels that you are mounting, and presuming the answers to the above questions are "No, not likely" (of course feel free to change your answer
), this is what I'd choose:
1) I'd run the panels as a series pair, so then I'd be going MPPT. (If you decide to do this, we can talk specific wire gauge vs. voltage drop, but the wires could be smaller since the voltage is higher.)
2) I'd choose either the Morningstar Sunsaver 15 MPPT, or the Blue Sky SB1524ix. We can get into detailed reasons if you like. I agree with you on the Victron. I love their stuff, but with lead-acid batteries I want temperature compensation on them, and you can't get that with the Victron controllers until you get into their very big units (way overkill for us). Boo! And yes, of course this is just one more "thing that won't be a thing" with lithiums, but most of us don't have those now (and they have other "things that are things").
Both of the controllers I mention above have remote temp comp. I like them both for different reasons (and they both have things I don't like, but on balance I'd still use one of the two vs. any others for your setup).
I've been running a Morningstar Sunsaver 15 MPPT for two years now with two 100 watt panels. Even though mine are ground panels (so I can site them advantageously, tilt them, etc.), I've only gotten the "you could have been taking in more than 15 amps except, sorry, the controller limited it" notification a couple of times (in July, on the prairie, in full sun). So for that reason I don't think a 15 amp controller is a limitation. After all, if you needed those extra few amps on those two perfect July days, how would you get by the rest of the year?
Actually, I'm going through this exact same decision process right now for a different project that has two of the same 100 watt panels. And I'm waffling between the same two controllers.
I do have a fondness for the "sturdy goodness" of the Morningstar, with its big heat sink fins, reasonably spaced terminal screws, and high voltage limit (even though I'm not using that now). No glitz, all function. And mine has worked perfectly for two years. Also, I helped a friend install one and it was making a barely detectable whistling noise. I contacted them (this was a year later), and they immediately shipped out a new one, with a tag in the box so we could send back the other one at no cost. No "Are you sure it's whistling?" or "We've never heard this complain before," or "We'll send you a new one once we receive the old one." Just bang and we had a new one. It's warrantied for five years.
What don't I like about it? Mainly that I have to use a Windows computer to program it. Also the remote meter (RM-1) isn't super fancy (it works well, but it doesn't show you multiple things at once, although it's intuitive to scroll through the various items).
On the other hand the Blue Sky has some slick features. The optional IPN Pro remote meter shows two fields at a time, can be used to program the controller, AND has a shunt and works as an amp counter battery meter (vs. a stand alone Victron BMV 700 or the like). It costs more than the Morningstar basic meter (and I already had a Victron BMV 700), but its slick (especially if you still need a battery monitor). Another cool thing is that if you were to add, say, another Blue Sky controller, the meter puts them both together to make them function as one. (The Morningstar would still work "fine" if you had two similar setups, with the same settings, and two Sunsavers; but it doesn't literally make them one controller, like the IPN Pro remote meter does.)
Also, the Blue Sky can use "end amps" to end the absorption time. This is sweet and avoids the figuring for how to set the parameters on the Morningstar (although you don't have to do it very often).
But of course there are some downsides too, as there seemingly can't be one controller with ALL the good features
. The max voltage is lowish (compared to Victron's 100 volts, or Morningstar's 75 volts). And they kind of use tricky terms (like a controller is a 40 amp controller but if you use X panels it's really only a 30 amp --- stuff like that). Not that that matters if you don't need the extra capacity*. And of their array of controllers, the 1524 is one of the higher voltage ones (the reason it's a thing is that with these controllers, if you go over the amp rating (on those two days in July ) they just slough off the extra; but if you go over the volt rating, they die).
Another minor negative (to me) is that it's an aluminum face plate for a heat sink vs. big ol' fins. But again, as long as it stays cool, that's what counts. The terminal screws are also a bit crowded, but that can be worked around. Especially if I didn't already have a battery monitor (or even if I had a Smart Gauge but wanted to add an amp counter), I'd be strongly considering the Blue Sky 1524ix plus the IPN Pro remote/shunt combo. It would also be a bit nicer if you added panels (as long as you stuck to something like pairs of 100 watts).
So, in summary, if it were me (and it kind of was/is since I have a similar setup), I'd run the pair in series, and then run either a Morningstar Sunsaver MPPT 15 with RM-1 remote meter, or a Blue Sky 1524ix with IPN Pro remote meter. A Smart Gauge is a nice addition for reading SOC, but an amp counter meter also has its place (so with the Morningstar I'd go with a Victron BMV, or with the Blue Sky the shunt/IPN Pro remote combo already do that).
If you are running a series pair, then you can still have a junction box on the roof, but you can also just run your single pair of 10AWG wires in through a roof gland (say a pair of right angled ScanStrut DS-H6 glands or a Go Power plate) and then put your switch/junction inside either the upper cabinet forward end or maybe in the overcab. I found that things would be kind of tight if I wanted to put a junction box on the roof (it would either make the panels have to be higher up than I wanted, have to be on the top hump, or in front of the panels - none of which appeal). Plus how convenient to have them "indoors."
I like a simple "on/off" M-series switch from Blue Sea, but there are other options.
If you want to give some input on whether any of this interests you, then if you like we could talk specific wire gauges and runs, etc. As always, these are my opinions (but there are many others of course).
BG
*So the 1524's recommended maximum PV open circuit voltage is 45.6, and the absolute max is 57 volts. So you might think, geez, that's plenty high. And it probably is, but it's slightly close and here is why: In the morning, JUST as the sun is coming up, you can hit higher voltages than you'd think. It's cold out, which makes the voltage higher, and the voltage isn't "working" yet so it's free to ramp up. So for example, let's say it's 15ºF at 6a.m. just as the sun is coming up, and you have your two Eclipse panels. The open circuit voltage rating (VOC) on those is 21.2 volts. Now let's say you are running them as a series pair. So now the VOC is 42.4 volts. Now let's go back to that 15ºF morning (or, brrr, let's not!). At that temperature in the morning, you'd hit 23.24 volts. So in series that would be 46.48. That's still fine on the 1524ix, but it would be a bit too close for comfort on, say, their 25 amp controller (50 volt dead max vs. 57 for the 1524).
Sorry for all the "math" above, but I just wanted to show how a "simple" pair of "12 volt" panels in series can actually get up there in voltage at times. It's just easy to have the 75 or 100 volt maximum of the Morningstar or Victron units. But, even -20ºF with the Eclipses would only be 45.72 volts on that record cold morning, so would still be fine with the 1524ix.
Are you likely to be adding more panels any time soon?
Do you think you may want to add ground panels?
For the two Eclipse panels that you are mounting, and presuming the answers to the above questions are "No, not likely" (of course feel free to change your answer
), this is what I'd choose:1) I'd run the panels as a series pair, so then I'd be going MPPT. (If you decide to do this, we can talk specific wire gauge vs. voltage drop, but the wires could be smaller since the voltage is higher.)
2) I'd choose either the Morningstar Sunsaver 15 MPPT, or the Blue Sky SB1524ix. We can get into detailed reasons if you like. I agree with you on the Victron. I love their stuff, but with lead-acid batteries I want temperature compensation on them, and you can't get that with the Victron controllers until you get into their very big units (way overkill for us). Boo! And yes, of course this is just one more "thing that won't be a thing" with lithiums, but most of us don't have those now (and they have other "things that are things").
Both of the controllers I mention above have remote temp comp. I like them both for different reasons (and they both have things I don't like, but on balance I'd still use one of the two vs. any others for your setup).
I've been running a Morningstar Sunsaver 15 MPPT for two years now with two 100 watt panels. Even though mine are ground panels (so I can site them advantageously, tilt them, etc.), I've only gotten the "you could have been taking in more than 15 amps except, sorry, the controller limited it" notification a couple of times (in July, on the prairie, in full sun). So for that reason I don't think a 15 amp controller is a limitation. After all, if you needed those extra few amps on those two perfect July days, how would you get by the rest of the year?
Actually, I'm going through this exact same decision process right now for a different project that has two of the same 100 watt panels. And I'm waffling between the same two controllers.
I do have a fondness for the "sturdy goodness" of the Morningstar, with its big heat sink fins, reasonably spaced terminal screws, and high voltage limit (even though I'm not using that now). No glitz, all function. And mine has worked perfectly for two years. Also, I helped a friend install one and it was making a barely detectable whistling noise. I contacted them (this was a year later), and they immediately shipped out a new one, with a tag in the box so we could send back the other one at no cost. No "Are you sure it's whistling?" or "We've never heard this complain before," or "We'll send you a new one once we receive the old one." Just bang and we had a new one. It's warrantied for five years.
What don't I like about it? Mainly that I have to use a Windows computer to program it. Also the remote meter (RM-1) isn't super fancy (it works well, but it doesn't show you multiple things at once, although it's intuitive to scroll through the various items).
On the other hand the Blue Sky has some slick features. The optional IPN Pro remote meter shows two fields at a time, can be used to program the controller, AND has a shunt and works as an amp counter battery meter (vs. a stand alone Victron BMV 700 or the like). It costs more than the Morningstar basic meter (and I already had a Victron BMV 700), but its slick (especially if you still need a battery monitor). Another cool thing is that if you were to add, say, another Blue Sky controller, the meter puts them both together to make them function as one. (The Morningstar would still work "fine" if you had two similar setups, with the same settings, and two Sunsavers; but it doesn't literally make them one controller, like the IPN Pro remote meter does.)
Also, the Blue Sky can use "end amps" to end the absorption time. This is sweet and avoids the figuring for how to set the parameters on the Morningstar (although you don't have to do it very often).
But of course there are some downsides too, as there seemingly can't be one controller with ALL the good features
. The max voltage is lowish (compared to Victron's 100 volts, or Morningstar's 75 volts). And they kind of use tricky terms (like a controller is a 40 amp controller but if you use X panels it's really only a 30 amp --- stuff like that). Not that that matters if you don't need the extra capacity*. And of their array of controllers, the 1524 is one of the higher voltage ones (the reason it's a thing is that with these controllers, if you go over the amp rating (on those two days in July ) they just slough off the extra; but if you go over the volt rating, they die).Another minor negative (to me) is that it's an aluminum face plate for a heat sink vs. big ol' fins. But again, as long as it stays cool, that's what counts. The terminal screws are also a bit crowded, but that can be worked around. Especially if I didn't already have a battery monitor (or even if I had a Smart Gauge but wanted to add an amp counter), I'd be strongly considering the Blue Sky 1524ix plus the IPN Pro remote/shunt combo. It would also be a bit nicer if you added panels (as long as you stuck to something like pairs of 100 watts).
So, in summary, if it were me (and it kind of was/is since I have a similar setup), I'd run the pair in series, and then run either a Morningstar Sunsaver MPPT 15 with RM-1 remote meter, or a Blue Sky 1524ix with IPN Pro remote meter. A Smart Gauge is a nice addition for reading SOC, but an amp counter meter also has its place (so with the Morningstar I'd go with a Victron BMV, or with the Blue Sky the shunt/IPN Pro remote combo already do that).
If you are running a series pair, then you can still have a junction box on the roof, but you can also just run your single pair of 10AWG wires in through a roof gland (say a pair of right angled ScanStrut DS-H6 glands or a Go Power plate) and then put your switch/junction inside either the upper cabinet forward end or maybe in the overcab. I found that things would be kind of tight if I wanted to put a junction box on the roof (it would either make the panels have to be higher up than I wanted, have to be on the top hump, or in front of the panels - none of which appeal). Plus how convenient to have them "indoors."
I like a simple "on/off" M-series switch from Blue Sea, but there are other options.
If you want to give some input on whether any of this interests you, then if you like we could talk specific wire gauges and runs, etc. As always, these are my opinions (but there are many others of course).
BG
*So the 1524's recommended maximum PV open circuit voltage is 45.6, and the absolute max is 57 volts. So you might think, geez, that's plenty high. And it probably is, but it's slightly close and here is why: In the morning, JUST as the sun is coming up, you can hit higher voltages than you'd think. It's cold out, which makes the voltage higher, and the voltage isn't "working" yet so it's free to ramp up. So for example, let's say it's 15ºF at 6a.m. just as the sun is coming up, and you have your two Eclipse panels. The open circuit voltage rating (VOC) on those is 21.2 volts. Now let's say you are running them as a series pair. So now the VOC is 42.4 volts. Now let's go back to that 15ºF morning (or, brrr, let's not!). At that temperature in the morning, you'd hit 23.24 volts. So in series that would be 46.48. That's still fine on the 1524ix, but it would be a bit too close for comfort on, say, their 25 amp controller (50 volt dead max vs. 57 for the 1524).
Sorry for all the "math" above, but I just wanted to show how a "simple" pair of "12 volt" panels in series can actually get up there in voltage at times. It's just easy to have the 75 or 100 volt maximum of the Morningstar or Victron units. But, even -20ºF with the Eclipses would only be 45.72 volts on that record cold morning, so would still be fine with the 1524ix.
1999 Concourse
Re: Just starting to investigate this question Pwm-Mppt
Ha, I am convinced that no one investigates an issue like Blue go,although the permutations and convolutions sometimes make my mind ache,I confess I sometimes think "is this over thought"....but not very many are as generous with their thoughts on a subject so 'I think' this forum is the perfect place for blue go..... Lots of nuts and bolts stuff and I love it.....The pwm/mppt question was not like the movie "the imaginarium of Dr Parnassus" where the good Dr and the devil fight for Souls.....
Here is what i take from the post....Blue sky 1524ix /pin pro remote meter/shunt/switch/temp cable sounds like an ideal setup.....if you go that route post a follow up of final costs and installation specifics so others can benefit. Rooney
Here is what i take from the post....Blue sky 1524ix /pin pro remote meter/shunt/switch/temp cable sounds like an ideal setup.....if you go that route post a follow up of final costs and installation specifics so others can benefit. Rooney
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Willywalderbeast
- Posts: 232
- Joined: July 17th, 2016, 5:00 pm
Re: Just starting to investigate this question Pwm-Mppt
Blue and Rooney, thank you for the input! Looked into those two systems and got to thinking if I need "the best" controller I can get.
Almost now leaning toward this https://www.renogy.com/rover-20-amp-mpp ... b_prd-desc
Cheap, checks all my need (especially the remote temp), simple... am I missing something?!?
Also to note, my stock system was keeping up with my needs and the wife and I like to move around a lot so the batteries also get to charge while driving so I'm assuming the two new panels and any new controller will more then fufil our needs.
Almost now leaning toward this https://www.renogy.com/rover-20-amp-mpp ... b_prd-desc
Cheap, checks all my need (especially the remote temp), simple... am I missing something?!?
Also to note, my stock system was keeping up with my needs and the wife and I like to move around a lot so the batteries also get to charge while driving so I'm assuming the two new panels and any new controller will more then fufil our needs.
Last edited by Willywalderbeast on May 5th, 2017, 7:18 am, edited 1 time in total.
Re: Just starting to investigate this question Pwm-Mppt
I am sad to say that electrical systems is my weakest area of knowledge when it comes to RV's.
Yes Blue has a lot of info about it (and it is appreciated) but it is mostly above my "pay grade"!
Yes Blue has a lot of info about it (and it is appreciated) but it is mostly above my "pay grade"!
Steve aka SMan
2004 Premier V10
2004 Premier V10
Re: Just starting to investigate this question Pwm-Mppt
That's a fair question: Do you need one of the "best" controllers? I have no idea as I have never tested a "best" and "economical" controller side-by-side under controlled conditions. I knew I'd be relying on mine to provide all of my daily electrical needs, and I had purchased expensive batteries, so the extra for a better controller didn't bother me at all (I spent around $300 for the Sunsaver and the remote meter). If I were shopping another controller, I'd be looking at the following:
1) Can I talk to people if there is a problem?
2) Is there a warranty? How will any defect/exchange be handled?
3) Can I custom program the charge settings? (I've never found a controller or charger yet wherein the standard settings match the charging specs of my batteries.)
3.5) What needs to be used to program it? Windows computer? Right from the display? Or?
4) Can I set the Equalization to be manual (i.e. no automatic equalization).
5) Is there remote temperature compensation and can the "factor" be changed? (For example, the two or three controllers I have set up had a factor higher than the batteries called for, but it was settable so I just changed it one time to the correct one.)
6) Is there a remote meter and does it look and function well to my eye? What data will it give me and how much is displayed all at once vs. having to scroll menus?
6.5) Does the remote display any history? How much?
7) How large a wire can the terminals take? Can I use ring terminals or are they the less desirable "push in and tighten screw" type? Are they so close together that I'm going to worry about positive and negative touching?
8) How does it dissipate heat? (Nice big fins? Fan? Do I have the clearance to mount it for good heat removal?)
9) Is the documentation good?
10) How does it handle excessive amps? Does it just slough them off with no worry? Or do I have to buy a controller that's overly large for 363 days of the year to accomodate those two days in July?
11) What is the max voltage over which it will die and is there any chance I'll come near that voltage on a record cold morning?
Of course what you can't really "look up" is how it's going to do at the actual charging. I've installed other "good" brand controllers in other people's rigs (Blue Sky, Victron), but have only used the Morningstar in my own situation which is pretty tightly known (what I mean is I know pretty much exactly how many amp hours I use every day, what conditions I'm in, what the history of the stats shows -- because it's me and I'm here every day). I've been surprised and impressed that 200 watts has pretty easily handled my loads. Is that because the controller is amazing? Because I kept voltage drop to a bare minimum? Because I'm often in reasonable sun? Would another setup have worked as well? And when my batteries eventually die, could they have lasted longer, or conversely, died sooner...? I can't really think of any way to answer those questions. What I do know for me as that because of how much I depend on solar for my daily energy needs, and because of how it relates to the overall cost of things, and because it was basically a one-time cost with no maintenance, insurance, or fuel required (if only I could say that about more things!), and just because of how my particular brain decides on things..... I had no problem forking over the $225 for the Morningstar controller. I'd buy it (or a similar one) again.
The other thing is that solar is really such a trickle anyway (in the grand scheme of things), that I wanted that trickle to be as strong as possible.
But as you bring up, a lot depends on use-case, on other priorities, and on how a particular person makes buying decisions. So while I can say what I did, and make a suggestion for what I would do if it were me..... that's not universal by a long shot.
1) Can I talk to people if there is a problem?
2) Is there a warranty? How will any defect/exchange be handled?
3) Can I custom program the charge settings? (I've never found a controller or charger yet wherein the standard settings match the charging specs of my batteries.)
3.5) What needs to be used to program it? Windows computer? Right from the display? Or?
4) Can I set the Equalization to be manual (i.e. no automatic equalization).
5) Is there remote temperature compensation and can the "factor" be changed? (For example, the two or three controllers I have set up had a factor higher than the batteries called for, but it was settable so I just changed it one time to the correct one.)
6) Is there a remote meter and does it look and function well to my eye? What data will it give me and how much is displayed all at once vs. having to scroll menus?
6.5) Does the remote display any history? How much?
7) How large a wire can the terminals take? Can I use ring terminals or are they the less desirable "push in and tighten screw" type? Are they so close together that I'm going to worry about positive and negative touching?
8) How does it dissipate heat? (Nice big fins? Fan? Do I have the clearance to mount it for good heat removal?)
9) Is the documentation good?
10) How does it handle excessive amps? Does it just slough them off with no worry? Or do I have to buy a controller that's overly large for 363 days of the year to accomodate those two days in July?
11) What is the max voltage over which it will die and is there any chance I'll come near that voltage on a record cold morning?
Of course what you can't really "look up" is how it's going to do at the actual charging. I've installed other "good" brand controllers in other people's rigs (Blue Sky, Victron), but have only used the Morningstar in my own situation which is pretty tightly known (what I mean is I know pretty much exactly how many amp hours I use every day, what conditions I'm in, what the history of the stats shows -- because it's me and I'm here every day). I've been surprised and impressed that 200 watts has pretty easily handled my loads. Is that because the controller is amazing? Because I kept voltage drop to a bare minimum? Because I'm often in reasonable sun? Would another setup have worked as well? And when my batteries eventually die, could they have lasted longer, or conversely, died sooner...? I can't really think of any way to answer those questions. What I do know for me as that because of how much I depend on solar for my daily energy needs, and because of how it relates to the overall cost of things, and because it was basically a one-time cost with no maintenance, insurance, or fuel required (if only I could say that about more things!), and just because of how my particular brain decides on things..... I had no problem forking over the $225 for the Morningstar controller. I'd buy it (or a similar one) again.
The other thing is that solar is really such a trickle anyway (in the grand scheme of things), that I wanted that trickle to be as strong as possible.
But as you bring up, a lot depends on use-case, on other priorities, and on how a particular person makes buying decisions. So while I can say what I did, and make a suggestion for what I would do if it were me..... that's not universal by a long shot.
1999 Concourse
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HoosierB
- **Forum Contributor**
- Posts: 473
- Joined: May 21st, 2015, 7:00 pm
- Location: South Bend, Indiana
Re: Just starting to investigate this question Pwm-Mppt
SMan wrote:I am sad to say that electrical systems is my weakest area of knowledge when it comes to RV's.
Yes Blue has a lot of info about it (and it is appreciated) but it is mostly above my "pay grade"!
Ditto. I have "left brain" oozing out of my ear.
"Wanda" – '01 Chinook Concourse XL V10
Re: Just starting to investigate this question Pwm-Mppt
What I liked about the blue sky setup above is integrated remote meter/shunt when a controller knows (with a sophisticated meter/shunt)it doesn't have to guess...I agree that it's a one time expense so it's fine if you wish to go large,and I do think that given that Blue runs a danfoss fridge it's incredible that 200 watts provides well....I also think that Customer Service is a big thing if there is any hitch it's good to have a wise word of advice....so I guess I totally agree....and once the setup is complete the setup should be a totally reliable system. Rooney
P.s. Thanks Blue and if you ever go permanent and want to sell your portable panels pm me,
P.s. Thanks Blue and if you ever go permanent and want to sell your portable panels pm me,