Jump to content

MPPT Solar Charge Controller


John and Ann

Recommended Posts

Hi All,

Wondering if anyone has the newer technology MPPT Charge Controller in their van. I've read they can be up to 30% more efficient in less than perfect sunlight than the previous PWM type which would be in most vans unless you've changed it. Perhaps the newer vans have them as standard, don't really know.

Would appreciate some feed back from anyone that has an MPPT controller:

  1. What was your motivation to have it installed or was it included in your build?
  2. What brand of controller do you have?
  3. Do you have a feel for the performance of an MPPT vs the older style PWM controller?
  4. What is the total wattage of your solar panels?

I'm asking because I'm thinking of changing out my current Xantrex C40, there's nothing wrong with it, just looking for more efficiency to avoid the generator blues.

Thanks in advance.smile.gif

John

Link to comment
Share on other sites

Hello John

This is a vexed question indeed. I went through the same process as you, trying to maximise power harvesting and minimise use (LED lights etc). My research on MPPT controllers was exhaustive an in the end, this paragraph, copied from an article I read, convinced me not to bother changing out my PWM controller:

"Just remember that most of the ratings are either optimistic, or are based on perfect conditions. Expect an average of 10-15% gain from an MPPT controller used with a 36 cell panel, as compared to a standard PWM controller. Under ideal conditions (cold ambient temperature, and a depleted battery) you may achieve as much as 30%"

My reasoning was that I don't spend a great deal of time at places where there is a "cold ambient temperature" and I never deplete my batteries greatly. For me, 10% - 15% gain was not worth the expense of changing. If my PWM controller dies completely (it is half-dead now, due to kamikaze frog damage), then I will replace it with an MPPT controller, but not before. Another thing to consider is this: On average, at what time of day do your batteries go onto float charge? If this occurs somewhere within an hour or two either side of midday, then having an MPPT controller will be of no help to you at all - your batteries are already peaked and will not accept more current, whatever you try. The exception is on cloudy days, where you will gain some benefit (as per the paragraph above.)

Hope this helps

Russ

Link to comment
Share on other sites

Hello John & Ann,

Our Kedron is only a month old and is fitted with a TriStar TS 45 solar controller, so I assume that is what Kedron is fitting these days. We have 3 x 130 W panels and 3 batteries. It's too early to make useful comment on the performance of this combination. <_<

Cheers,

Bill

Link to comment
Share on other sites

PS to my previous post

I should have added that the TS 45 controller is a PWM type controller - not the newer MPPT type.

Sorry,

Bill

Link to comment
Share on other sites

G'Day Russ,

Thanks for your reply, indeed it helps. I've sort of ended up in the same place on this question as you (minus the kamikaze frog). I believe that changing to LiFePO4 batteries has in itself added efficiency to the charge cycle.

Another thing to consider is this: On average, at what time of day do your batteries go onto float charge? If this occurs somewhere within an hour or two either side of midday, then having an MPPT controller will be of no help to you at all - your batteries are already peaked and will not accept more current, whatever you try. The exception is on cloudy days, where you will gain some benefit.

It's a bit early to get a grip on the time taken to go onto float as we are not actually in travelling mode, parked up at home getting ready. Early indications are that the system would likely go onto float somewhere about midday as you suggested.


G'Day Bill,

That's interesting, wonder why they keep changing. Did you have the option of either one or the other. I would be expecting that most quality builders that provide solar systems on their vans would opt for MPPT as the relative difference from new is minor compared to the outlay on the van.

PS to my previous post

I should have added that the TS 45 controller is a PWM type controller - not the newer MPPT type.

Cheers

John

Link to comment
Share on other sites

G'day John,

The original plan from Kedron showed that we were to have a Xantrax C35 solar controller but, on delivery we found that we had the TS 45 instead. Both are PWM devices. We haven't asked why the change was made and were unaware of MPPT technology.

While we tried to do our homework on what went into the van ther were lots of things that we knew little or nothing about. Last year when we were travelling with our camper trailer we latched on to as many Kedron owners as we could - to pick their brains. But what we got were answers to our questions plus some other assorted advice. In other words, we didn't know all of the questions that we could have asked. Wisdom of hindsight is what we are now gaining.

It has been an interesting ride getting this far and is bound to get more interesting as time goes on. :huh:

Cheers,

Bill

Link to comment
Share on other sites

Hi Bill,

The original plan from Kedron showed that we were to have a Xantrax C35 solar controller but, on delivery we found that we had the TS 45 instead. Both are PWM devices. We haven't asked why the change was made and were unaware of MPPT technology.

It seems sometimes things just happen (I'm assuming with the best of intentions), even if you visit them every day during the build as I did. I've got a Four Seasons Hatch which I specifically didn't want, after much discussion, I agreed to leave it there as it seemed way to difficult to undo.

While we tried to do our homework on what went into the van there were lots of things that we knew little or nothing about.

I trawled all manner of related forums, didn't ask too many questions as most of them had already been asked and answered were I looked. Being a sparky with construction industry experience not to mention being a bit of a technology tragic I knew what I wanted. We'd not lived in a van since the mid 70's so had to rely on opinions of others about layout and functionality, needless to say there are tings I would do differently, the hindsight thingy you are also experiencing. There are a few things that I think I definitely got right/wrong.

Got Right (factory firsts)

  1. Specifying LED lighting throughout, including strips under overhead cupboards (one fluoro did sneak into the front boot and I had to change the swivel and rangehood downlights to LED myself).
  2. Specifying Accumulators on the water pumps.
  3. Specifying Fusion Audio System with a wired remote in the external TV hatch.

Got Right (but, they tried to convince me I was wrong)

  1. Insisting on the Victron 12/2000/80 Inverter Charger despite getting a few phone calls trying to talk me out of it. In the end I had to indemnify them to get it across the line, they were that persistent. It's been a brilliant piece of gear and made the transition to LiFePO4 batteries a doddle.

Got Wrong:

  1. Didn't fit the Auto Satellite Dish, got talked out of it by popular misconception that they are more trouble than they are worth, re: trees and line of site to satellite. I now know I could work around this and would be a small price for the convenience.
  2. Didn't take enough close-up photo's during the build, particularly when it was all wired up and the external skin had not yet been fitted.
  3. No HDMI between satellite receiver and external TV hatch ( can't even retro-fit it, believe me I've tried)
  4. Didn't fit USB charging outlets (12vdc connected version), I could think of at least 5 locations for one of these.

All in all though it's a brilliant van and we thoroughly enjoy our yearly escape.... can't wait for late May when we'll be off again.

It has been an interesting ride getting this far and is bound to get more interesting as time goes on.

That you can be sure of, I'm cursed with being a habitual tinkerer with too much time on my hands, so there's always a project or two (dozen) on the go with the van, cruiser or our semi-rural property (the later comes a sad last on the prioritisation list.

Enjoy the road, travel safe.

John

Link to comment
Share on other sites

[*]No HDMI between satellite receiver and external TV hatch ( can't even retro-fit it, believe me I've triedJohn

John,

this was an issue for me as well, although to be fair, HDMI wasn't as pervasive when our van was built as it is these days. To overcome the issue I have installed a 5.8 Ghz wireless HDMI transmitter/receiver combo, which I got from Jaycar Electronics. I have since seen them on the 'net (Cablechick) a bit cheaper. Basically you fit the TX unit at the source (DVD player, sat-box etc) and the RX wherever you need it (in the outside hatch, for example.) The Rx unit plugs into your telly or monitor. Note: this unit does not have separate audio-out jack, so if you use a monitor as a tv, then you need to have a separate arrangement for your audio.

I love it. I can have the telly anywhere I want in or out of the van. I even use it to tune my satellite dish because I can set up my little 7" monitor, that I purchased for my video camera, right next to the dish and use the VAST tuning page to hone in the dish. It saved me the expense of buying one of those up-market tuners for the dish. The TX unit has a range of about 25 metres and seems to penetrate the skin of the van reasonably well. I have no problems locating the telly anywhere inside the annex and, up until now, have not had any "blind spot" when setting the satellite dish up away from the van.

I purchased a second Rx unit so that I could leave one set up where we usually locate the telly plus have a "roving" unit for other occasions. Note: Only one Rx unit can be used at a time. Additionally, they have a remote Infra-red unit. This means that the Rx unit picks up the remote control signal from your God-stick and sends it through to the Tx unit. The Tx unit has a jack in it, into which you plug a supplied Infra-red repeater. You locate the repeater in front of the source device and the remote control commands are repeated into it. Magic!

The first Tx/Rx combo come as a matched pair and simply work, straight out of the box. The second RX had to be "paired" to the Tx unit, a process that required me to press a button for a few seconds. I can't say enough about them, they are great.

Cheers

Russ

Link to comment
Share on other sites

Thanks John,

That is quite an interesting & informative epistle.

We visited the factory only once a week once build started - that's all that we could manage. Not having been in a trade or industry (I was a Maths/Physics teacher) I had to work largely on trust along with information gathered, as I said.

We were advised against four seasons hatches (Rod Kyd, from memory)and when we questioned Kedron about this we were told that they now refuse to fit them because of sealing problems - so we have two Fantastics.

Our lighting is almost all LED with a fluoro over the sink and whatever is in the range hood. The LEDs in the ceiling must be switched on at the fitting even though there are wall switches for some of them. This is not a Kedron feature - it comes with the type of fitting that they use. It's OK for me but Wendy is too short to reach them. A short length of dowel extends her reach, but she has to remember where she put it each time.

We had not thought of accumulators for the pumps - wish we had.

On board entertainment is not a big thing for us. We watch very little TV and rarely use the radio except for a bit of news and weather. We chose not to spend big on an Auto Satellite dish for that reason. We have not yet decided whether to buy the gear for VAST.

I will probably not get involved with anything that requires a knowledge of the wiring in the kerb side van wall. I have photos which I will keep but that is all.

We have no USB sockets - hadn't thought of that.

Our inverter is 1600 W. Hopefully that will be sufficient. Originally we did not include one at all but requested a 1800 W unit just before build started. We finished up with the 1600 W job without being told.

To date we haven't managed to have our first trip with the van, so we are not sure how it will all come together. Originally we planned to hit the road just after delivery but an assortment of minor issues put the hobbles on us. Not the least of the issues was where to park the van when we are home. My original plan isn't going to work in the longer term, so we are having a flat area dug, concreted and covered elsewhere. Expensive, yes, but for ease and peace of mind essential.

I have followed your posts on the LiFePO4s with interest and a fair degree of admiration.

Cheers,

Bill

Link to comment
Share on other sites

Hi Russ,

Good post, very handy indeed, food for thought (for many I suspect)

To overcome the issue I have installed a 5.8 Ghz wireless HDMI transmitter/receiver combo, which I got from Jaycar Electronic

Good tip, I'm onto it, I've got two TV's so I presume I can use a HDMI splitter before the transmitter if I want that option.

I even use it to tune my satellite dish because I can set up my little 7" monitor

Now that can be classed as thinking outside the box(square). I got the expensive gizmo as a Christmas gift from my boys and I love it, but your solution is a very viable alternative.

I'm sure your post will give many cause to look into their own options.

Thanks

John

Link to comment
Share on other sites

Hi Bill,

We were advised against four seasons hatches (Rod Kyd, from memory)and when we questioned Kedron about this we were told that they now refuse to fit them because of sealing problems - so we have two Fantastics.

Tell me about it, mine has leaked, right from the outset, hopefully it's sorted now. I've got two Fantastics as well, but raise you one in the bathroom. laugh.gif

Oh, I've just changed the centre Fantastic to be a van pressurisation fan complete with oiled/foam intake filter, be interesting to see how it performs. Promising so far, blows heaps of air out of the rangehood exhaust outlet (blows out the flame on a gas lighter), door vent and Four Seasons hatch. I modified this to accomplish the task:

post-1034-0-07657500-1333274740_thumb.jpg

The accumulators are a dead easy retro fit, just buy the accumulators (Jabsco is what I have one on each drinking and shower water) online and grab a few fittings from the local caravan supply store. Your pumps will love you for it, even more than you will enjoy the reduced noise of the cycling.

Could be that your inverter has an apparent power rating of 1800va and a real power rating of 1600w (my Victron unit seems big at 2000va but the real power rating is 1600w). "W" and "VA" are not the same thing, the difference is important and understood by sparky type people, for the most everyone else they are a source of confusion.

To date we haven't managed to have our first trip with the van, so we are not sure how it will all come together. Originally we planned to hit the road just after delivery but an assortment of minor issues put the hobbles on us. Not the least of the issues was where to park the van when we are home. My original plan isn't going to work in the longer term, so we are having a flat area dug, concreted and covered elsewhere. Expensive, yes, but for ease and peace of mind essential.

The best things come to those who are patient and wait, I'm sure your turn is just around the corner.

Regards

John

Link to comment
Share on other sites

You win John, :)

Our hatch in the bathroom is not a Fantastic. The label says Ventline. Our bathroom is not ensuite. The original plan was for a 21 ft external van with full ensuite but we were concerned about ATM so we chopped a foot off at the expense of the ensuite. We will do long trips but do not plan to live full time in it, so the combined shower/toilet should work OK - it is bigger than the standard Kedron set-up.

I'm really interested in your pressurising set-up and will consider doing something similar when dust entry eventually bugs us badly. The accumulator fit is something else that may happen down the track. At the moment I have to bleed the waterlines from the main pump which continues to hunt after all taps are off. I thought that the factory would have seen to that.

I remember vexing over VA & W when I was trying to understand how our home air con is rated. The technician's reply to my question reminded me of the cliche "Trust me, I'm a doctor." I may have trusted him if he had said "power factor" because I fully understand the concept of phase difference for V & I in inductive and capacitive AC circuits. I just needed the nudge when it came to VA.

Cheers,

Bill

Link to comment
Share on other sites

I have installed a 5.8 Ghz wireless HDMI transmitter/receiver combo, which I got from Jaycar Electronics.Russ

Hi Russ,

I've been and had a bit of a look around and there seems to be quite a few different models, mostly they run on 5vdc from a 240v plug pack. Which is it that you have? Do you have a 12vdc model or run them via a plug pack or 12vdc-5vdc switchmode converter? I'm asking because I try, as best I can, to have as much of this stuff as 12vdc.

Thanks in advance.

John

Link to comment
Share on other sites

Hello,

I have really enjoyed reading this thread except I don't understand all these electrical / electronic things :D Sadly, my maker forgot to add that part of the brains kit that understands this stuff. I am jealous of you all. I understand "on" and "off" on switches and "positive" and "negative".....that is it!

Regards

Colin

Link to comment
Share on other sites

Don't be jealous Colin,

Sometimes too much knowledge can be just that - too much. Life can be so much simpler if we cruise blissfully through it. :)

Cheers,

Bill

Link to comment
Share on other sites

Hi All,

I have to agree with Bill the more gear you have all the more things to go wrong.

I abide by the KISS rule.(Keep It Simple, Stupid)

Cheers John

Link to comment
Share on other sites

Hi Russ,

I've been and had a bit of a look around and there seems to be quite a few different models, mostly they run on 5vdc from a 240v plug pack. Which is it that you have? Do you have a 12vdc model or run them via a plug pack or 12vdc-5vdc switchmode converter? I'm asking because I try, as best I can, to have as much of this stuff as 12vdc.

Thanks in advance.

John

Hi John

For the time being I am running the gear from the inverter when camping, but will be either making or buying some DC - DC converters for them. The model I have is the Digitech AR1877 (which is the matched pair) and then I later purchased the AR1876 (which is a receiver only.) There is no limit to how many AR1876's you can have because you can only operate one at a time. I have one that is permanently fixed in place and the other is a "roving" unit. You can buy additional matched pairs and use them simultaneously because they have a range of frequencies at which they will operate.

Cheers

Russ

Link to comment
Share on other sites

G'Day All

Thanks for the info Russ.

Ann said that she agrees with you John [JHerron] icon_rolleyes.gificon_lol.gif Funny that. Though I'm sure she will ask me "Why is it we can't we watch the Satellite TV outside" .....bahahaha.

Oh so true Bill. smile.gif

Like Bill said, don't be jealous Colin. We've all got an area(s) of interest that are different, how boring would it be if we all had the same knowledge. I guess that's what makes this type of Forum so valuable, the knowledge pool and peoples willingness to share helps fill in the blanks.

Cheers

John

Link to comment
Share on other sites

Yes - diversity of interest & ability is good and that goes for life generally.

I have been a KOG member for only a short time, but thoroughly enjoy reading what others have to say. In many cases I have no intention of doing what someone else has done, but there are some real pearls there.

This series of posts started about MPPT controllers (which I had to Google to find Maximum Power Point Tracking) but branched in several directions as other points emerged It has been a very interesting few days watching the development.

Thanks to those who had something to say - great stuff!

Cheers,

Bill

Link to comment
Share on other sites

  1. Didn't take enough close-up photo's during the build, particularly when it was all wired up and the external skin had not yet been fitted.

Enjoy the road, travel safe.

John

Link to comment
Share on other sites

Hi Bill,

Tell me about it, mine has leaked, right from the outset, hopefully it's sorted now. I've got two Fantastics as well, but raise you one in the bathroom. laugh.gif

Oh, I've just changed the centre Fantastic to be a van pressurisation fan complete with oiled/foam intake filter, be interesting to see how it performs. Promising so far, blows heaps of air out of the rangehood exhaust outlet (blows out the flame on a gas lighter), door vent and Four Seasons hatch. I modified this to accomplish the task:

post-1034-0-07657500-1333274740_thumb.jpg

The accumulators are a dead easy retro fit, just buy the accumulators (Jabsco is what I have one on each drinking and shower water) online and grab a few fittings from the local caravan supply store. Your pumps will love you for it, even more than you will enjoy the reduced noise of the cycling.

Could be that your inverter has an apparent power rating of 1800va and a real power rating of 1600w (my Victron unit seems big at 2000va but the real power rating is 1600w). "W" and "VA" are not the same thing, the difference is important and understood by sparky type people, for the most everyone else they are a source of confusion.

The best things come to those who are patient and wait, I'm sure your turn is just around the corner.

Regards

John

Link to comment
Share on other sites

Hi Bill,

Tell me about it, mine has leaked, right from the outset, hopefully it's sorted now. I've got two Fantastics as well, but raise you one in the bathroom. laugh.gif

Oh, I've just changed the centre Fantastic to be a van pressurisation fan complete with oiled/foam intake filter, be interesting to see how it performs. Promising so far, blows heaps of air out of the rangehood exhaust outlet (blows out the flame on a gas lighter), door vent and Four Seasons hatch. I modified this to accomplish the task:

post-1034-0-07657500-1333274740_thumb.jpg

The accumulators are a dead easy retro fit, just buy the accumulators (Jabsco is what I have one on each drinking and shower water) online and grab a few fittings from the local caravan supply store. Your pumps will love you for it, even more than you will enjoy the reduced noise of the cycling.

Could be that your inverter has an apparent power rating of 1800va and a real power rating of 1600w (my Victron unit seems big at 2000va but the real power rating is 1600w). "W" and "VA" are not the same thing, the difference is important and understood by sparky type people, for the most everyone else they are a source of confusion.

The best things come to those who are patient and wait, I'm sure your turn is just around the corner.

Regards

John

Hi John,

Where did you buy the components to modify the Fanstatic to a van pressurisation fan and what was the cost?

Link to comment
Share on other sites

Hi John,

Where did you buy the components to modify the Fanstatic to a van pressurisation fan and what was the cost?

Hi Col,

I bought hatch covers last year from the US. At the time I posted in this thread http://www.kedronown...ch=1 $256.00 for 3 inluding freight. The rest I made myself with bits from Bunnings, Clark Rubber and what I had at home, I'll take it back off over the next day or two and post a photo of the filter I made that slides in behind the grille. Aside from the hatch covers the bits cost me about $40.00 or so.

Patent Pending...... bahahaha

Cheers

John

Link to comment
Share on other sites

Hi Col,

I bought hatch covers last year from the US. At the time I posted in this thread http://www.kedronown...ch=1 $256.00 for 3 inluding freight. The rest I made myself with bits from Bunnings, Clark Rubber and what I had at home, I'll take it back off over the next day or two and post a photo of the filter I made that slides in behind the grille. Aside from the hatch covers the bits cost me about $40.00 or so.

Patent Pending...... bahahaha

Cheers

John

Thanks John,

I'll keep an eye out for the details.

Cheers

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...