Solar The Solar Panel Thread

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
I was put onto this site last week by someone on here in regard to another subject and came across this section which I thought would be of interest to the you both @Boots in Action and @mikerezny ............... the author I've found to be pretty good as Ive read some of his books and to a non techo find them easy to understand while being a good source of info that has been field tested not just bench.

https://www.gorv.com.au/10-rv-solar-myths/


Thanks @Drover for the link. I have seen that before and as you said, it is simple and easy to understand for those not so technical. I like the one about myth # 5 on charging and compressor fridges (and beer chilling/drinking!!) but in a lot of cases this can be overcome with more solar and batteries and closer observation of charging and use of capacity - and of course less cold drinking!! The other one about the advantages of MPPT controllers is only half the story and the simple explanation. Good MPPT controllers now have less than 5% loss in operation (not 10 to 15%!!) and it does not take into account the greater current production in dimmer conditions at all times of the day, where PWM units would give you 100% of bugger all, whilst the MPPT is able to convert any voltage in panels to amps, be they only small. It also does not account for lesser losses in cabling if connections are in series among other things. But still good to explain and dispel many myths that float around. However, there is ONLY one thing that is certain, and that is the result of your own field testing properly recorded. Beats theory every time!!
 

Drover

Well-Known Member
Nov 7, 2013
12,723
19,450
113
QLD
You forgot to mention that with so much rubbish gear available nowadays, big dollars doesn't mean much.
 

millers

Active Member
Mar 25, 2011
282
246
43
Adelaide
Hi all,
I am hoping that while the Tech Heads are in attendance that I could float a proposal for a setup by you. I have a 16.49 with battery provision but have not installed a battery. A friend of mine has discarded a battery so I am going to use that as a trial for setting up the system with solar and a DC-DC charger (either the CTEC 250S Dual or Projecta IDC25) I will use the IDC25 as an example. Currently our power needs are minimal and we do not free camp, but I would like to set it up for free camping. All lights are solar and we have a water pump.

So the setup / changes will be as follows:
a. 6 B&S used throughout for all runs associated with connecting tug, van battery and fridge;
b. Use of anderson connectors for power runs;
c. Ignition isolation on the tug to all power connectors to the van;
d. When not connected to 240V:
i. 12V DC from tug into the DC input of IDC25;
ii. ability to connect solar into the solar input of the IDC25;
iii. van battery charged by IDC25 and van load from battery;
e. When connected to 240V:
i. 12V DC from SETEC into DC input of IDC25 (tug DC isolated);
ii. ability to connect solar into the solar input of the IDC25;
iii. van battery charged by IDC25;
iv. van load from SETEC.

I need to check all of the SETEC connections (as per the discussion above) to make sure that I use the right ones but was thinking of using a single DC connection through seperate fuses for load and into the IDC25.

My rationale is as follows:

DC-DC means that van charger can utilise tug power and adjust accordingly;
Solar option can be utilised when camping;
SETEC when powered allows van battery to be isolated and charged correcly.

Any comments appreciated

Cheers
Stephen
 

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Hi all,
I am hoping that while the Tech Heads are in attendance that I could float a proposal for a setup by you. I have a 16.49 with battery provision but have not installed a battery. A friend of mine has discarded a battery so I am going to use that as a trial for setting up the system with solar and a DC-DC charger (either the CTEC 250S Dual or Projecta IDC25) I will use the IDC25 as an example. Currently our power needs are minimal and we do not free camp, but I would like to set it up for free camping. All lights are solar and we have a water pump.

So the setup / changes will be as follows:
a. 6 B&S used throughout for all runs associated with connecting tug, van battery and fridge;
b. Use of anderson connectors for power runs;
c. Ignition isolation on the tug to all power connectors to the van;
d. When not connected to 240V:
i. 12V DC from tug into the DC input of IDC25;
ii. ability to connect solar into the solar input of the IDC25;
iii. van battery charged by IDC25 and van load from battery;
e. When connected to 240V:
i. 12V DC from SETEC into DC input of IDC25 (tug DC isolated);
ii. ability to connect solar into the solar input of the IDC25;
iii. van battery charged by IDC25;
iv. van load from SETEC.

I need to check all of the SETEC connections (as per the discussion above) to make sure that I use the right ones but was thinking of using a single DC connection through seperate fuses for load and into the IDC25.

My rationale is as follows:

DC-DC means that van charger can utilise tug power and adjust accordingly;
Solar option can be utilised when camping;
SETEC when powered allows van battery to be isolated and charged correcly.

Any comments appreciated

Cheers
Stephen

Thanks for the info @millers and the opportunity to be of assistance. Firstly what are the details of the battery you are going to use - Gel or AGM - and its capacity and age/condition because this will have a bearing on what you have to do. Secondly I am not familiar with the IDC25, but have a reasonable idea about the CTEK 250S which @Duncanblake36 has used in his system . There has been lots of details about the ability of the van SETEC providing power and its "limited" ability to fully charge an AGM battery and to a lesser extent a GEL battery owing the limited charge voltage of the SETEC being only 14.0 volts. As detailed on other posts Gel require 14.2 to 14.4 volts at 25C while AGM may require 14.4 to 14.7 volts to achieve FULL capacity. This may not be problem if you are mainly on the grid but could become an issue later if wanting to get the best out of your van battery. See also @Axl post about failing batteries. Also note the latest post by @Duncanblake36 regarding the conflict in charging arrangements when van is connected to the 240 volt system and the Setec is trying to charge the battery at the same time that the solar panels are feeding power to the controller in the CETEK 250S. As a result, all his power including charging and voltage control for the solar panels and battery charging the van battery is through the 250S. Suggest you have a look at @Duncanblake36 's set up before making any further decisions. I look forward to your answers so correct advice can be given for you to decide.
 
  • Like
Reactions: Travman

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Hi all,
I am hoping that while the Tech Heads are in attendance that I could float a proposal for a setup by you. I have a 16.49 with battery provision but have not installed a battery. A friend of mine has discarded a battery so I am going to use that as a trial for setting up the system with solar and a DC-DC charger (either the CTEC 250S Dual or Projecta IDC25) I will use the IDC25 as an example. Currently our power needs are minimal and we do not free camp, but I would like to set it up for free camping. All lights are solar and we have a water pump.

So the setup / changes will be as follows:
a. 6 B&S used throughout for all runs associated with connecting tug, van battery and fridge;
b. Use of anderson connectors for power runs;
c. Ignition isolation on the tug to all power connectors to the van;
d. When not connected to 240V:
i. 12V DC from tug into the DC input of IDC25;
ii. ability to connect solar into the solar input of the IDC25;
iii. van battery charged by IDC25 and van load from battery;
e. When connected to 240V:
i. 12V DC from SETEC into DC input of IDC25 (tug DC isolated);
ii. ability to connect solar into the solar input of the IDC25;
iii. van battery charged by IDC25;
iv. van load from SETEC.

I need to check all of the SETEC connections (as per the discussion above) to make sure that I use the right ones but was thinking of using a single DC connection through seperate fuses for load and into the IDC25.

My rationale is as follows:

DC-DC means that van charger can utilise tug power and adjust accordingly;
Solar option can be utilised when camping;
SETEC when powered allows van battery to be isolated and charged correcly.

Any comments appreciated

Cheers
Stephen
Hi @millers again, had a further look at you ideas and items A and B - good. Item C , you could use a VSR in the line to the van battery and it would be better than a relay wired through the ignition system. Item D i to iv when (not connected to 240 volt power) look good and quite feasible too. E i is debatable. I would take the DC voltage from the van battery rather than the SETEC, but @Duncanblake36 would be able to help you there. Items E ii to iv are good and doable. There will be other "tech heads" that will probably come up with ideas but I think that the best answers will come from a member who has already done it and achieved outstanding success - @Duncanblake36 . Good luck.
 

Drover

Well-Known Member
Nov 7, 2013
12,723
19,450
113
QLD
Anyone got the portable solar panels- any recommendations

I've been using a set of 120w panels from Aldi for a number of years now, they get a lot of use and seem to perform very well, I did replace the regulator as like a lot of portables they only have a cheapy.


Hey @millers are you going to fix panels to your roof ???
 

millers

Active Member
Mar 25, 2011
282
246
43
Adelaide
Hi @Boots in Action and thanks for the reply.

Extra question: How many anderson plugs (was going to use the 50A):

a. One for both fridge (15A) and battery charging (40A max)
b. Two fridge and battery charging seperate;

The initial battery is an AGM 110 Ah which after 24 hours of no load/charge is holding 12.74 V. I say initial as it was given to me due to "surplus to requirement" by another caravaner. The IDC 25 is a 25 amp 3 stage battery charger, with manual select for battery type (GEL/AGM/WET/Calcium). Inputs to the IDC 25 are "Alternator" with VSR (12.8V) and Low Voltage Mode (11.9V) and solar (23V max). Priority is solar.

The described set up would not rely on the SETEC to directly charge the battery, instead it would be the "alternator" input to the IDC25 and letting the IDC25 control battary charging voltage. This means that there is never a conflict between the IDC and the SETEC when charging. Current thinking is to use a DPDT relay which is swirched by the 12V DC from the SETEC to change the "alternator" input to the IDC 25.

The current tug installation has a relay and I like the idea that it isolates on the ignition, put it down to personel preference. Also noting that the IDC 25 has low voltage cut out on the input.

The rational for switching the van DC load from battery (when running on the car) to SETEC (when connected to 240V) is so that when the van is "home" the IDC 25 sees only the battery and is not influenced by any DC load to determine charge state. This should provide the best maintenance for the battery with no effort (just plug the van into its 240V power point in the shed).

I will need to look at the SETEC connections to determine which of them are appropriate to use, my initial assumption was that it had one output and then split into fuses, but this maynot the case. So will investigate this on the weekend prior to buying all of the bits.

Hi @Drover with the solar the initial thinking was to but anderson connectors both front and back and utilise portable pannels. Put at present I do not have any pannels. As the wiring for the portables is basicly seperare from the roof (except coming to a common input point). So the roof solar will be a seperate project. Will need to see how much off grid we do and circumstance. In general though will try and run with portables first.

Cheers Stephen
 

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Anyone got the portable solar panels- any recommendations

Hi @Travman , what are your 12 volts demands as this will decide what sort of panels and their size output. Do you want folding type or just one large panel. Lots of choices on Ebay at the right price but be careful in your choice as some are not as good as others in output or solar control type. Also, if purchase more than one, you will have to consider connecting them in the best way. Let us know what you are going to do with the panels and their charge requirement - batteries and type. I have 1 X 200 watt and 1 X 180 watt , or at least that is what they are rated at, and an efficient MPPT controller and charge output in amps can sometimes be over 20 amps in my system. Normally though it only about 16 amps total in good conditions. A lot depends on the quality and type of controller PWM or the dearer more efficient MPPT type. There is a lot of info on panels and controllers on this site, so suggest you go back through a few of them and work out what suits you best dollar wise and quality wise.
 
  • Like
Reactions: Travman

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Hi @Travman , what are your 12 volts demands as this will decide what sort of panels and their size output. Do you want folding type or just one large panel. Lots of choices on Ebay at the right price but be careful in your choice as some are not as good as others in output or solar control type. Also, if purchase more than one, you will have to consider connecting them in the best way. Let us know what you are going to do with the panels and their charge requirement - batteries and type. I have 1 X 200 watt and 1 X 180 watt , or at least that is what they are rated at, and an efficient MPPT controller and charge output in amps can sometimes be over 20 amps in my system. Normally though it only about 16 amps total in good conditions. A lot depends on the quality and type of controller PWM or the dearer more efficient MPPT type. There is a lot of info on panels and controllers on this site, so suggest you go back through a few of them and work out what suits you best dollar wise and quality wise.

Hi @Travman , I had a look on Ebay and noticed this 200 watt panel which has a Platinum MPPT controller on the back of the folding panel. To me, a good unit at a good price for a folding panel. Specs read good and ":Supposed" German cells. Probably better than the last one I bought a year or two ago and cheaper AND with MPPT controller, not the cheap PWM type. If I was buying again, I would look carefully at this one. Lots of false figures and description floating around but at around $150.00 on special, may be a good buy?? Remember all max output is calculated at max open circuit voltage multiplied by max open circuit current under perfect conditions in the lab. Expect to have about 17 volts when charging (good with an MPPT controller!!) and an output of around 10 amps in good cool sunny conditions. When the panel/s get hot output can drop by at least 10%. This for your information, but please do your own research and comparisons.

https://www.ebay.com.au/itm/200W-Fo...20928006?_trkparms=aid=555018&algo=PL.SIM&ao=
 

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Hi @Boots in Action and thanks for the reply.

Extra question: How many anderson plugs (was going to use the 50A):

a. One for both fridge (15A) and battery charging (40A max)
b. Two fridge and battery charging seperate;

The initial battery is an AGM 110 Ah which after 24 hours of no load/charge is holding 12.74 V. I say initial as it was given to me due to "surplus to requirement" by another caravaner. The IDC 25 is a 25 amp 3 stage battery charger, with manual select for battery type (GEL/AGM/WET/Calcium). Inputs to the IDC 25 are "Alternator" with VSR (12.8V) and Low Voltage Mode (11.9V) and solar (23V max). Priority is solar.

The described set up would not rely on the SETEC to directly charge the battery, instead it would be the "alternator" input to the IDC25 and letting the IDC25 control battary charging voltage. This means that there is never a conflict between the IDC and the SETEC when charging. Current thinking is to use a DPDT relay which is swirched by the 12V DC from the SETEC to change the "alternator" input to the IDC 25.

The current tug installation has a relay and I like the idea that it isolates on the ignition, put it down to personel preference. Also noting that the IDC 25 has low voltage cut out on the input.

The rational for switching the van DC load from battery (when running on the car) to SETEC (when connected to 240V) is so that when the van is "home" the IDC 25 sees only the battery and is not influenced by any DC load to determine charge state. This should provide the best maintenance for the battery with no effort (just plug the van into its 240V power point in the shed).

I will need to look at the SETEC connections to determine which of them are appropriate to use, my initial assumption was that it had one output and then split into fuses, but this maynot the case. So will investigate this on the weekend prior to buying all of the bits.

Hi @Drover with the solar the initial thinking was to but anderson connectors both front and back and utilise portable pannels. Put at present I do not have any pannels. As the wiring for the portables is basicly seperare from the roof (except coming to a common input point). So the roof solar will be a seperate project. Will need to see how much off grid we do and circumstance. In general though will try and run with portables first.

Cheers Stephen

@millers , always use Anderson Plug connectors for all high current devices. Most are rated to 50A and so cabling must also be rated that high if you are really going to flog the current through them Normally, you will only ever run 15 A or so unless using a piece of heavy equipment outside the van. If you do not have any solar set- up already, a simple and easy way is to have an Anderson plug at the side of the van and run the cable from the plug directly to the POS and NEG terminals of the van battery. If using the IDC25 with its own internal solar controller, the wires would need to run to that unit first. In addition, if using the IDC25 as your solar controller, it will be necessary to bypass the controllers on the back of the solar panels. You do not have to remove them, but connect the wiring from the output line of the panels (BEFORE IT GOES TO THE CONTROLLER ON THE BACK OF THE PANEL!!) and run a line with Anderson plug on the other end to connect to Anderson plug on van. That way, the solar panels do not lose their ability to be used to charge other items when necessary. Picture of my van Anderson connections on the outside of my Penguin. One is for solar and the other one is for my "smart" charger to charge battery at home or anywhere where there is 240 volt power. @Drover can give you more ideas that this system can be used for.

27 Jul 17 (1).JPG
 

mikerezny

Well-Known Member
Sep 11, 2016
1,630
2,728
113
Mount Waverley, VIC
Hi @Travman , I had a look on Ebay and noticed this 200 watt panel which has a Platinum MPPT controller on the back of the folding panel. To me, a good unit at a good price for a folding panel. Specs read good and ":Supposed" German cells. Probably better than the last one I bought a year or two ago and cheaper AND with MPPT controller, not the cheap PWM type. If I was buying again, I would look carefully at this one. Lots of false figures and description floating around but at around $150.00 on special, may be a good buy?? Remember all max output is calculated at max open circuit voltage multiplied by max open circuit current under perfect conditions in the lab. Expect to have about 17 volts when charging (good with an MPPT controller!!) and an output of around 10 amps in good cool sunny conditions. When the panel/s get hot output can drop by at least 10%. This for your information, but please do your own research and comparisons.

https://www.ebay.com.au/itm/200W-Folding-Solar-Panel-Kit-12V-Mono-Camping-Caravan-Boat-Charging-Power-USB/352420928006?_trkparms=aid=555018&algo=PL.SIM&ao=
Hi @Boots in Action,
I had a quick look at the regulator. A platinum one that looks similar can be picked up for less than $35. They also weigh only 142g. This seems way too cheap and too light to be a 10A MPPT controller. A 10A MPPT controller will need to have a reasonably sized transformer / coil inside to do the voltage conversion and this makes them larger and heavier than a PWM.

What leads you to believe it is a real MPPT controller and not yet another one from the family of PWM controllers? The front label says nothing about it being an MPPT controller.

The panel specification is Vmp of 18V and Imp of 11.12A. So in good sunlight at 25C one would expect 200W into an MPPT controller. With a load or a low SOC battery, and assuming 97% efficiency, as in the ad, one should expect 194W into a battery at around 14.4V = 13.47A. This would exceed the 10A rating of the controller.

But, for $150 for a 200W portable panel, 5m lead, and an anderson plug it still seems good value even with a PWM regulator.

At around 10A, I would suggest mounting the regulator close to the battery and ensure adequately sized leads between the panel and the controller to minimise the voltage drop.

cheers
Mike
 

Drover

Well-Known Member
Nov 7, 2013
12,723
19,450
113
QLD
@millers , If you were going to fit panels to the roof (200w) I would suggest not bothering with the tug to van charging system as it just added expense as your solar would do the job possibly better, but since you are going portable then a seperate anderson for fridge and van supply would be the go, just by a bag of andersons off Ebay, a mob in Melb I buy mine at 20 a time for about $25, they have stood the test of time so no need to pay $15 each and they are 50amp. just need to check though if you are gong to use 6 and 8 B&S cable then get the 6 B&S ones as the cable will fit them all and you won't have to trim cable.....

So for your fridge set up, a fridge switch fitted at the back of the fridge depending on model where and fit an anderson on your big cable and off the fridge circuit as you will have to reduce the size to hook up the fridge and it allows for easy removal if needed, mind the heater wires will feel like they are near melting when it running, a 45 amp breaker up near the battery and a 45 breaker for the tug supply to the van, I would go the D250S myself in the van and run it to the battery with probably a 35 amp fuse, the Setek I would just use its standard set up to the battery........it will draw from the battery for your 12v needs and charge when your on 240, as you won't have panels out when on 240 there will be no conflict....the fridge or van 12v supply is a good spot to piggy back power for cams etc as well....I have also run a light from the fridge cable at back of fridge once, fridge running on gas and fridge cable plugged into back of ute at draw bar, I needed a big extension lead,.....just a thought of extra use. Big Mal is 22ft.

For the portable panels since you want to use a DC-DC unit then I would run a cable from the D250s to an external anderson where you can plug in your panels, ( you may need to make a buzz bar if 2 lots of cables wont fit the D250S , so the cables go to the bar and a single run to the D250s) also Ebay has 8 B&S extension leads 10mt for $60 with plugs, perfect for panels, a mod to the panel to allow you to either plug directly to a battery via the panel regulator or plug directly to the 250s bypassing the panel regulator can be discussed later, you cannot plug the panel into the D250S via it's regulator, it won't like, it wont work anyway.

I would also add an external anderson plug with a direct fused line to the battery, this can be handy for running compressors, engel, or even an extra solar panel using its own regulator, it allows 2way flow of power, I just painted mine instead of buying some coloured plug which will only take the same coloured plug....Unless your not paying attention it isn't a problem.

My set up doesn't have anyway of charging from the tug, I have a seperate 240 charger which will charge the batteries, 200w of solar on the roof running thru a good quality PWM controller, a 120w portable which has been modded to either use its own controller or can bypass it and connect direct to the PWM in van, 2x100a GEL batteries connected up to to complete the show, this set up allows me to camp for as long as I like as we don't do van parks nowadays, no need for the tug charge system as who wants to run a vehicle for hours when camped by a creek somehow, if its cloudy for days and days I will just use the LRPS, hardly ever needed to but run it to do the washing....even if we plug into 240 it usually just runs the fridge, HWS and kettle solar does the batteries which in turn run lights, TV and STB's......

A panel will probably be only good for about 70% of what they rate them and buying off ebay is hot and miss but certainly with a bit of research is better than being ripped off from the off road/camping shops...........

With roof panels I think the need for a tug charging system is a bit of a legacy from the pre solar days, money spent on something that not really needed, if you have set up your solar properly it should charge it all, who wants to run a vehicle for hours .

Not anyway a techo description but I hope it helps, campfire speak......but it works.


Some light reading the link will lead you to other sections.... https://caravanchronicles.com/guides/how-to-connect-two-batteries-in-parallel/
 
  • Like
Reactions: Boots in Action

Drover

Well-Known Member
Nov 7, 2013
12,723
19,450
113
QLD
Why would anyone buy a 10amp unit anyway, mind if the panel is good, buy it, chuck the regulator in the bin and buy a decent 35a MPPT which will perfom well and give extra info, $150 buys some good gear now.....if my PWM wasn't one of the few really good ones I would be ditching it for newy MPPT. but most of the portable panels I've seen have rubbish units fitted and a google on them shows they mostly retail for $20.............
Plus a well performing proper MPPT contoller will make Booties happy @Boots in Action
 
  • Like
Reactions: Boots in Action

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
@millers , If you were going to fit panels to the roof (200w) I would suggest not bothering with the tug to van charging system as it just added expense as your solar would do the job possibly better, but since you are going portable then a seperate anderson for fridge and van supply would be the go, just by a bag of andersons off Ebay, a mob in Melb I buy mine at 20 a time for about $25, they have stood the test of time so no need to pay $15 each and they are 50amp. just need to check though if you are gong to use 6 and 8 B&S cable then get the 6 B&S ones as the cable will fit them all and you won't have to trim cable.....

So for your fridge set up, a fridge switch fitted at the back of the fridge depending on model where and fit an anderson on your big cable and off the fridge circuit as you will have to reduce the size to hook up the fridge and it allows for easy removal if needed, mind the heater wires will feel like they are near melting when it running, a 45 amp breaker up near the battery and a 45 breaker for the tug supply to the van, I would go the D250S myself in the van and run it to the battery with probably a 35 amp fuse, the Setek I would just use its standard set up to the battery........it will draw from the battery for your 12v needs and charge when your on 240, as you won't have panels out when on 240 there will be no conflict....the fridge or van 12v supply is a good spot to piggy back power for cams etc as well....I have also run a light from the fridge cable at back of fridge once, fridge running on gas and fridge cable plugged into back of ute at draw bar, I needed a big extension lead,.....just a thought of extra use. Big Mal is 22ft.

For the portable panels since you want to use a DC-DC unit then I would run a cable from the D250s to an external anderson where you can plug in your panels, ( you may need to make a buzz bar if 2 lots of cables wont fit the D250S , so the cables go to the bar and a single run to the D250s) also Ebay has 8 B&S extension leads 10mt for $60 with plugs, perfect for panels, a mod to the panel to allow you to either plug directly to a battery via the panel regulator or plug directly to the 250s bypassing the panel regulator can be discussed later, you cannot plug the panel into the D250S via it's regulator, it won't like, it wont work anyway.

I would also add an external anderson plug with a direct fused line to the battery, this can be handy for running compressors, engel, or even an extra solar panel using its own regulator, it allows 2way flow of power, I just painted mine instead of buying some coloured plug which will only take the same coloured plug....Unless your not paying attention it isn't a problem.

My set up doesn't have anyway of charging from the tug, I have a seperate 240 charger which will charge the batteries, 200w of solar on the roof running thru a good quality PWM controller, a 120w portable which has been modded to either use its own controller or can bypass it and connect direct to the PWM in van, 2x100a GEL batteries connected up to to complete the show, this set up allows me to camp for as long as I like as we don't do van parks nowadays, no need for the tug charge system as who wants to run a vehicle for hours when camped by a creek somehow, if its cloudy for days and days I will just use the LRPS, hardly ever needed to but run it to do the washing....even if we plug into 240 it usually just runs the fridge, HWS and kettle solar does the batteries which in turn run lights, TV and STB's......

A panel will probably be only good for about 70% of what they rate them and buying off ebay is hot and miss but certainly with a bit of research is better than being ripped off from the off road/camping shops...........

With roof panels I think the need for a tug charging system is a bit of a legacy from the pre solar days, money spent on something that not really needed, if you have set up your solar properly it should charge it all, who wants to run a vehicle for hours .

Not anyway a techo description but I hope it helps, campfire speak......but it works.


Some light reading the link will lead you to other sections.... https://caravanchronicles.com/guides/how-to-connect-two-batteries-in-parallel/

@Drover , spoken and explained just like a REAL "Tech Head". Noted some of my thoughts have got through to you at last, but I have no difficulty in passing the baton to you when it comes to versatile usage of your electrical set up. Take a bow!!
 

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Why would anyone buy a 10amp unit anyway, mind if the panel is good, buy it, chuck the regulator in the bin and buy a decent 35a MPPT which will perfom well and give extra info, $150 buys some good gear now.....if my PWM wasn't one of the few really good ones I would be ditching it for newy MPPT. but most of the portable panels I've seen have rubbish units fitted and a google on them shows they mostly retail for $20.............
Plus a well performing proper MPPT contoller will make Booties happy @Boots in Action


All very true @Drover . But I guess as you have said before on this forum, everyone's needs are different and the same can be said about willingness to expend hard earned cash if not necessary. One only finds out about how to improve things by listening to others and not making the same mistake. Thanks for the acknowledgement too. And yes, I am smiling and seeing a lot of members improve their system and get the benefit of the latest technology.
 

Boots in Action

Well-Known Member
Mar 13, 2017
2,054
1,805
113
Ferny Grove, Queensland
Hi @Boots in Action,
I had a quick look at the regulator. A platinum one that looks similar can be picked up for less than $35. They also weigh only 142g. This seems way too cheap and too light to be a 10A MPPT controller. A 10A MPPT controller will need to have a reasonably sized transformer / coil inside to do the voltage conversion and this makes them larger and heavier than a PWM.

What leads you to believe it is a real MPPT controller and not yet another one from the family of PWM controllers? The front label says nothing about it being an MPPT controller.

The panel specification is Vmp of 18V and Imp of 11.12A. So in good sunlight at 25C one would expect 200W into an MPPT controller. With a load or a low SOC battery, and assuming 97% efficiency, as in the ad, one should expect 194W into a battery at around 14.4V = 13.47A. This would exceed the 10A rating of the controller.

But, for $150 for a 200W portable panel, 5m lead, and an anderson plug it still seems good value even with a PWM regulator.

At around 10A, I would suggest mounting the regulator close to the battery and ensure adequately sized leads between the panel and the controller to minimise the voltage drop.

cheers
Mike

Yes, agreed Mike @mikerezny. As you and I know, the output advertised is highly unlikely to ever be reached as STC is not going to be duplicated in the real world, so I guess that a minimum PWM or MPPT (if genuine??) would be able to cover most circumstances if the rating is just under "stated??" output. In fact I made a mistake and gave a link to the wrong unit that only states that it is MPPT. The solar panel that has the Platinum MPPT ??? controller is linked below.

www.ebay.com.au/itm/GISTA-200W-12V-Folding-Solar-Panel-Kit-Caravan-Camping-Power-USB-Charging-AU/222807206939?_trkparms=aid%3D555018%26

I have seen these in the field but never tested them. They do not have all the bells and whistles on an LED screen like the dearer ones and yes, if weight is not there, it is unlikely to have a heavy enough coil to handle the current as for a genuine MPPT controller. Once again, let the buyer beware!! There are a lot of "shonkies" out there and only by doing a lot of research does one not fall into fake unit. Even poor @Bellbirdweb purchased a unit that did not work properly at all before getting it returned and had to go for the much dearer and proper Epever. My LD solar works well and had a two year warranty and came from Foster NSW. I have checked your calculations and agree that 13.47 amps would be theoretically possible under ideal conditions approaching STC. Even if only 80% operation, current would amount to over 10 amps. I would not want to run a controller at its max for long periods unless of course the manufacturer has a 20% tolerance built into the unit. Note that solar efficiency of panel is rated at 24%!! and specs are supposed to be within 2% plus or minus. Notice even @Drover is becoming electrically minded with all his easy and simple electrical systems.
 

Drover

Well-Known Member
Nov 7, 2013
12,723
19,450
113
QLD
I'll have you know, once upon a time I wanted to get into electrical stuff, mainly radios but decided to have a life of excitement and adventure, sometimes too much adventure mind.......some of the old stuff from ham radio study is still there ( thats the days when you built one to pass the test) but I don't speak tech babble as it puts me and others to sleep but babble on it does remind me of stuff forgotten sometimes.......
 
Last edited:
  • Like
Reactions: mikerezny

mikerezny

Well-Known Member
Sep 11, 2016
1,630
2,728
113
Mount Waverley, VIC
Yes, agreed Mike @mikerezny. As you and I know, the output advertised is highly unlikely to ever be reached as STC is not going to be duplicated in the real world, so I guess that a minimum PWM or MPPT (if genuine??) would be able to cover most circumstances if the rating is just under "stated??" output. In fact I made a mistake and gave a link to the wrong unit that only states that it is MPPT. The solar panel that has the Platinum MPPT ??? controller is linked below.

www.ebay.com.au/itm/GISTA-200W-12V-Folding-Solar-Panel-Kit-Caravan-Camping-Power-USB-Charging-AU/222807206939?_trkparms=aid%3D555018%26

I have seen these in the field but never tested them. They do not have all the bells and whistles on an LED screen like the dearer ones and yes, if weight is not there, it is unlikely to have a heavy enough coil to handle the current as for a genuine MPPT controller. Once again, let the buyer beware!! There are a lot of "shonkies" out there and only by doing a lot of research does one not fall into fake unit. Even poor @Bellbirdweb purchased a unit that did not work properly at all before getting it returned and had to go for the much dearer and proper Epever. My LD solar works well and had a two year warranty and came from Foster NSW. I have checked your calculations and agree that 13.47 amps would be theoretically possible under ideal conditions approaching STC. Even if only 80% operation, current would amount to over 10 amps. I would not want to run a controller at its max for long periods unless of course the manufacturer has a 20% tolerance built into the unit. Note that solar efficiency of panel is rated at 24%!! and specs are supposed to be within 2% plus or minus. Notice even @Drover is becoming electrically minded with all his easy and simple electrical systems.
Hi @Boots in Action,
since you mentioned it was a platinum controller, I searched for one that looked like the one in your original link. Then I took the specs from the platinum one. I would be very surprised if either of them is a genuine MPPT. To cheap and to light. A 10A Victron weighs around 500g compared to only 142g. The difference is that a PWM controller only needs a mosfet to switch the current and they weigh bugger all. An MPPT controller uses a coil / transformer to convert the voltage.

cheers
Mike