Solar regulator position.

iana · Guru

Solar regulator position.

Phillipn · Guru

Yes, it is best to have the regulator close to the battery.

I have seen a portable solar panel and the regulator was attached to the stand and not to the back of the panel. I can`t remember the brand name.

I have a 120w portable folding panel and I have bypassed the regulator with Anderson plugs. The wires that came with the panel has been replacer with 8 B&S cable that plugs into the ute or caravan to Dc- Dc chargers. Their was too much voltage loss with the wire that was supplied with the panel.

I can still use the regulator on the back of the panel if I wish to.

If you try to remove the regulator from the panel you could damage the panel. Someone on this site may know how to remove one.

DeBe · Guru

Ive purchased 4 x 160W folding solar panels, & all the fited regulators did not actualy work properly (too high voltage) The regulators were held on with Velcro, I just removed them & use a beter reg at the battery.

Jaahn · Guru

iana wrote:
Its my understanding that the regulator for solar panels to battery is placed as close to the battery as possible to avoid voltage drop, thus allowing the batteries to reach full charge. The problem I have is, I have noticed that all portable panels on sale have the charger fastened to the back of the panel.
If I am looking at setting up a portable system, would I not be better to buy a standard panel, and mount the regulator at the batteries, and run the panel lead to that via a plug/socket?
Just a note, we are totally dependent on 12v power when free camping, including the fridge which is not gas, capturing the morning sun is what I am about.

Hi iana smile

YES and YES smile

You can buy a portable panel or I suggest two smaller ones(or more). Getting them in and out etc can be easier with smaller ones... Then get some good sized wires to wire them to a connector on the end of the main cable back to the regulator. If possible put the regulator close to the battery permanently wired in with a good accessible plug like an anderson style where you can use it easily. It will work much better that a bought set.

I made up a set like that previously with 4 x 80W panels, I could use 2 or 4 as I needed. I used a small water resistant electrical box with 4 marine sockets to plug the panels into on the end of the longish cable. I also made up a small diameter SS marine cable to secure the panels also. If you make up a generous size electrical cable, both rating and length, it will enable you to chase the sun all day without having to move most times. biggrin

You can just set up the panels facing east before you go to bed, and sleep-in knowing the sun is working for you, if the terrain allows it aww

If you want some advice on the panels and regulator to buy just ask. I have bought several lots off ebay without problems.

Jaahn

-- Edited by Jaahn on Thursday 20th of September 2018 04:01:59 PM

iana · Guru

Thanks Jaahn and the rest who replied, we just did 6 days free camping along the beach inside the Ningaloo reef WA. Power went critical the first night, mind you there was a footy final on (satellite). What I noticed for the next 3 days was the panels on top of the van failed to charge the last two segments of the gauge, but when we got a cool day and wind, the charge went all the way full charge. It dawned on me that the panels are loosing efficiency because of heat (they were warm days and little wind).
No charge until the sun is fairly high in the sky. It seems that for us, we will have to have angled panels to get the morning sun and the panels are cool. At present I am exploring ideas, one of which was plan "A" the origional, where I would be able to mount a panel on the roof of the Ute canopy, a simple matter of turning the ute to face East, or Nor-east.
The ute is wired up with a DC-DC charger and aux battery, and has a solar reg built in. I have a heavey cable that can supply the caravan via the ute, which I can feed to the 12v system, by-passing the van batteries.

Portable solar panels on the ground, subject to theft? wind blowing them over, trip hazard etc. Early days yet, but the plan is in motion.

swamp · Senior Member

HI
Face panels north gives the best average production .
The angle varies a lot according to season and location [long and lat].
solarelectricityhandbook.com/solar-angle-calculator.html

200watts is a good match for 100-120ah battery . Under the 50% = 50-60ah discharge limit this panel size will recharge by lunch.

PeterD · Guru

iana wrote:
Its my understanding that the regulator for solar panels to battery is placed as close to the battery as possible to avoid voltage drop, thus allowing the batteries to reach full charge. The problem I have is, I have noticed that all portable panels on sale have the charger fastened to the back of the panel.

The panels purchased that way frequently are of poor quality. At least the regulators are. The regulators frequently have a fixed output voltage. You are far better off purchasing the panels separately and getting yourself a quality regulator that has several output voltage selections. You then can mount your regulator near the battery resulting better charging for your batteries and you will probably not pay much more.

Warren-Pat_01 · Guru

G'day Ian,
As you have discovered solar panels, like batteries perform best around 25 degrees. After that they drop off a bit (there are probably charts showing this in the forum's history) but here at home in the tropics, those temps are exceeded very day.

When you buy kits complete with the "regulator" attached to the panels, the regulator too cooks in the heat all day so the best thing is to either remove it or bypass it if possible & have a better regulator fitted near the battery. Since I wrote the post about "cats among the pigeons, cans of worms, etc" I found a site that showed the drop in output power when panels are installed flat (on the roof of the van) can be as high as 38% - I think Jaahn said it was around 25%.

The panels that show on my profile are 20w - hinged together. I have another set of two + a single one. I chose that size due to the small space available in our Eagle. Jaahn obviously has more storage space for his 80w panels.

Jaahn, what are the marine plugs & sockets that you use? I've used the "old fashioned" two pin LV plugs & sockets - similar to www.jaycar.com.au/2-pin-32-volt-15-amp-in-line-socket/p/PS2073 on my panels. I could use Anderson plugs/skts but I've had a couple of bad experiences with them.

Peter_n_Margaret · Guru

The 25 degrees quoted for standard panel performance is the panel cell temperature, not the ambient air temperature.
The panels can get quite a lot hotter than the air which is why good ventilation makes a difference to panel output (probably up to 10% or maybe more).
At lower temperatures (like in Tasmania) they can perform even better than at 25C too.
Some cells perform better at elevated temperatures than others.
Cheers,
Peter

T1 Terry · Guru

It's a trick, gotta be, I got bucket loads poured on me when I started posting this sort useful information :lol: Great to see a better understanding of the effects of heat on solar panel voltage output and a bit on the current output, just not as much as it does the voltage. The cable size from the panel to the regulator is very much a voltage drop due to resistance thing and heat increases the resistance as well, so what appears to be a ridiculous over size may not be the case if the cable is in the sun running over a hot surface in the peak heat period of the day, which coincides with the peak panel output time as well so worth the small increase in cost in the long run.

T1 Terry

oldtrack123 · Guru

T1 Terry wrote:
It's a trick, gotta be, I got bucket loads poured on me when I started posting this sort useful information :lol: Great to see a better understanding of the effects of heat on solar panel voltage output and a bit on the current output, just not as much as it does the voltage.
[a]The cable size from the panel to the regulator is very much a voltage drop due to resistance thing and heat increases the resistance as well, so what appears to be a ridiculous over size may not be the case if the cable is in the sun running over a hot surface in the peak heat period of the day, which coincides with the peak panel output time as well so worth the small increase in cost in the long run.

T1 Terry

[a] Ambient temp or cable temp makes very little difference to the resistance of the copper cable,

That is why copper is commonly used.

https://www.engineeringtoolbox.com/resistivity-conductivity-d_418.html

PeterD · Guru

The picture below shows the effect of temperature on a cell. Note the suppression of voltage with the rise of temperature.

Solar cell - effect of temperature.png

iana · Guru

Thankyou PeterD and others including you Terry. I am concluding that the reason why the batteries did not reach full charge on the "Light wind" hotter days was because of heated panels, which is a bit of a concern because summer is hardly here. As I said the batteries fully charged when the weather turned colder.

There is a couple of other things, one that the wiring from the two panels on the van roof is 7 meters (Yep Jayco) from the regulator to the batteries, so there may be a bit of a voltage drop there.

And I have a third panel mounted on the roof running to another regulator, but I notice that the voltage is fluctuating a bit by about 1.5v, I am thinking that it is possibly caused by the panel diodes, and a shadow caused by the roof vent. Else the two regulators are fighting each other.

Since I have to look at our solar capacity to work during the winter months as well (Full time), I am putting some serious thought into angled panels. This will explain some of my further weird questions.

PeterD · Guru

iana wrote:
There is a couple of other things, one that the wiring from the two panels on the van roof is 7 meters (Yep Jayco) from the regulator to the batteries, so there may be a bit of a voltage drop there.

And I have a third panel mounted on the roof running to another regulator, but I notice that the voltage is fluctuating a bit by about 1.5v, I am thinking that it is possibly caused by the panel diodes, and a shadow caused by the roof vent. Else the two regulators are fighting each other.

Since I have to look at our solar capacity to work during the winter months as well (Full time), I am putting some serious thought into angled panels. This will explain some of my further weird questions.

Are you saying that the installers mounted portable panels on the van and just used their regulators? If so the first thing to do is to get yourself a quality regulator to mount near the battery. Then ditch those regulators and rehash the system.

"Else the two regulators are fighting each other." No, the controllers in there are not smart enough to "fight" each other. They are just simple regulators that allow the maximum capacity current to flow from the regulator if the output terminal voltage is low enough. When the battery voltage rises to the set voltage of the regulator, the regulator simply reduces the current flow to prevent overcharging of the battery.

Upgrade what you have with a new regulator and see if you have sufficient recharge power first.

iana · Guru

No No, roof mounted panels 150w each to a 30amp regulator, then from the regulator, 7 meters of cable to the batteries.

I have since mounted another 150w and the regulator for this is about 500mm from the batteries.

3 150w panels, two 30w regulators.

-- Edited by iana on Sunday 23rd of September 2018 05:40:02 PM

Roy E · Senior Member

Ian,
Some of the info posted here already is pretty good and the recommendation to get a decent controller, is IMHO, the best. Get an MPPT one with input capacity to handle say, 100 volts and perhaps 20 amps. Ditch the controller attached to the panels, wire the two panels in series to double the output voltage and halve the current (roughly) and existing wiring will be adequate.
Hopefully, the MPPT controller you get will have battery temp monitoring capability along with a battery temp sensor. Mount controller close to battery and with adequate air space/ventilation.
Because the output from the solar panels drops as they heat up, it's a good idea to have panels mounted clear of roof or ventilation holes in panel mount frame for air to circulate under panels.
I believe the angle the panels are is not that important in that it only reduces effective area by not being perpendicular to the sun.
Cheers,
Roy.

T1 Terry · Guru

PeterD wrote:
The picture below shows the effect of temperature on a cell. Note the suppression of voltage with the rise of temperature.

This one is from Kyocera showing voltage drop from a 140w 12v nom. panel. Draw a line straight down from where the output curve drops off and you can clearly see why a hot panel can't get the battery voltage high enough to finish the boost charging phase, especially for flooded cells that require 14.8v and 16.5v for an equalise cycle. 75v is not an uncommon internal panel temp even in a European summer, that is why Kyocera publish it in their data, can you imagine just how hot the panels get in an Australian summer?

I've added individual voltage lines across the top so it's easier to see 10v plus what ever is the point the output drops off.

Kyocera 140w panel with single voltage increments.jpg

Jaahn · Guru

iana wrote:
No No, roof mounted panels 150w each to a 30amp regulator, then from the regulator, 7 meters of cable to the batteries.
I have since mounted another 150w and the regulator for this is about 500mm from the batteries.
3 150w panels, two 30w regulators.
-- Edited by iana on Sunday 23rd of September 2018 05:40:02 PM

Hi iana smile

My suggestion would be to shift the main 30A regulator to near the batteries and rewire the panels to this new position. Possibly by a better more direct route. You could even wire the three panels in parallel to one regulator if they all have similar VMP.

Depending on the type of regulators they usually do not interfere with each other much. However when they get the batteries up to voltage they will not be smooth in control.

Use bigger wire if you are going to rewire and get more power for "free" instead of loosing it in crappy wires. biggrin Note any shadowing of a panel will affect its output by major amounts.

Jaahn

iana · Guru

OK found something, the regulator that controls the single 150w panel is faulty, internal no connection to the solar panel.

Watching the charging amps of the two panels in parallel, observed the input at one stage to be over 20 amps, so connecting all three panels to the same regulator being a 30amp unit, may blow it up?

Question, if I were to buy another regulator, would I be better to buy MPPT type, rather than PWM which is what we have now?

oldtrack123 · Guru

iana wrote:
OK found something, the regulator that controls the single 150w panel is faulty, internal no connection to the solar panel.

Watching the charging amps of the two panels in parallel, observed the input at one stage to be over 20 amps, so connecting all three panels to the same regulator being a 30amp unit, may blow it up?

Question, if I were to buy another regulator, would I be better to buy MPPT type, rather than PWM which is what we have now?

The combined output of the three panels will be under 30A, so the one 30A reg should be ok

PWM versus MPPT get prepared?? biggrin

T1 Terry · Guru

oldtrack123 wrote:
iana wrote:
OK found something, the regulator that controls the single 150w panel is faulty, internal no connection to the solar panel.

Watching the charging amps of the two panels in parallel, observed the input at one stage to be over 20 amps, so connecting all three panels to the same regulator being a 30amp unit, may blow it up?

Question, if I were to buy another regulator, would I be better to buy MPPT type, rather than PWM which is what we have now?

The combined output of the three panels will be under 30A, so the one 30A reg should be ok
PWM versus MPPT get prepared??

Provided the panels don't exceed 80% efficiency and no room for additional portables if required. This was part of the opening post "If I am looking at setting up a portable system, would I not be better to buy a standard panel, and mount the regulator at the batteries, and run the panel lead to that via a plug/socket?" Kinda rules out using the same solar controller to do all the solar and rules out MPPT in series. Maybe an MPPT controller for the portables to keep the cable size down, but the issue then is getting it work with a second controller whether it be PWM or MPPT. There are controllers that can do that and additional systems that master control multiple same brand MPPT controllers, but the cost and complexity out weights the potential gains. Not impossible just financially and complexity issues make it impractical.

T1 Terry

iana · Guru

We are now pretty desperate, the one regulator can't get two 100 AH gel batteries up past 3/4 charged (going by the bar graph), alarms going off at 4am. No TV, or any other use of power, except for the 12v fridge. The regulator a Topraysolar TPS1230 is getting very hot around the sides.

An interesting situation, I had to disconnect the wires off the regulator, and reconnected them red positive, black negative. Noted the screen was not showing the correct indication. Tested the solar incoming cables, and some one at Jayco has crossed the wires, so now black is positive and red negative. Changed the wires around and was then getting a charge. I am suspicious that the second regulator has been damaged by this, and also could be the reason for the high power usage, as Tony and blocking diodes suggest, I have damaged the internal valve and the power may be being feed back out at night.

The Topraysolar TPS1230 internals is old technology, I pressed all the IC's back in their sockets and checked connections. Am looking at purchasing a Projecta SC245 $219, which can handle 45 amps, so can take the three panels and an external portable when required. It will have to come from Sydney.

Had a Sales guy in a shop try to sell me a MPPT type, the only one they had with enough to handle the amperage for $600.

To nite I will disconnect the panels to see if the power lasts longer.

Ian.

-- Edited by iana on Tuesday 2nd of October 2018 05:34:45 PM

iana · Guru

Hi warren, interest in the subject seems to have waned, so I haven't posted up-dates. At the moment I am waiting on the arrival of a new Projecta 45A to replace the two units currently fitted, one with an open connection to the solar panels, and the other, the built in blocking diode may be faulty.

The system on the van did not have blocking diodes between panels, Tony's post and that article recommends I fit them, how ever finding diodes that can handle the amperage has been difficult. Altronics have the stud type rated at 25A which I could use.

As we are now in a Perth caravan park on 240v all the problems have disappeared for now. Probably Tuesday will begin the job of fitting, the regulator is being air-bagged from Melbourne.

T1 Terry · Guru

iana wrote:
Hi warren, interest in the subject seems to have waned, so I haven't posted up-dates. At the moment I am waiting on the arrival of a new Projecta 45A to replace the two units currently fitted, one with an open connection to the solar panels, and the other, the built in blocking diode may be faulty.

The system on the van did not have blocking diodes between panels, Tony's post and that article recommends I fit them, how ever finding diodes that can handle the amperage has been difficult. Altronics have the stud type rated at 25A which I could use.

As we are now in a Perth caravan park on 240v all the problems have disappeared for now. Probably Tuesday will begin the job of fitting, the regulator is being air-bagged from Melbourne.

Hi Ian, how many diodes do you need? We had to buy 500 pcs to get the ones that will do the job, so we have a reasonable stock still available wink Drop me a pm with your mailing address and how many you need and I'll get them out to you in the next post.

T1 Terry

iana · Guru

Progress so far, have run a 9mm auto twin core from the new regulator position to the battery, this 3.5m lead replaces the 7m 4.2mm dia. cable of the Jayco install. The new solar controller certainly looks the part, rated for 45 amps, looks well built, nice big heat sink. To day I mount the controller, and run new wires up to one of the solar panels.
Jobs to do next week, install blocking diodes, and change the polarity of the wrongly connected Jayco installed wiring to the panels.

iana · Guru

Progress so far, cables installed. I have two diodes now to work with, but an unexpected event has occurred. Removing the first panel I find that the Jayco installer has broken the locking lugs on the connection box lid, the gaffer tape holding the lid in place had come adrift (Jayco install), and the lid was missing. Terminals, studs corroded etc. Spare parts not available of course, but I have cut the base off another junction box and put the entire over the original and stekaflexed it in position.
The cables were connected to the wrong polarity, and I am highly suspicious that the regulator may have been damaged at the initial installation by this.
It is pretty amazing that Jayco would allow a caravan to leave the factory like this, there have been so many faults, it is unbelievable. PS the other panel was also had the solar panel junction box lid gaffa tapped in place, but I hope I got it in time and repaired it (I know I repaired it earlier, last year or so), will see when I get to it.

PeterD · Guru

iana wrote:
It is pretty amazing that Jayco would allow a caravan to leave the factory like this, there have been so many faults, it is unbelievable.

Was the solar install a factory or an agent install? I don't know what happens lately but a few years ago the vans left the factory as a standard van and the agents fitted the extras.

iana · Guru

This would have been a factory installation, the solar wires in the roof are foam filled in the channels. It was ordered with a compressor fridge, which blew fuses all the time, a grey water tank that really upset the weight and balance, and an extra solar panel, both having been wired with reverse polarity and the lids of the panel junction boxes gaffa tapped on. Very poor show Mr Jayco. And if I listed everything which I will one day, its a pretty shameful example of manufacture.

T1 Terry · Guru

Hi Ian, have those diodes arrived yet? Mail out of Mannum can be a bit slow because we living in the c-o-u-n-t-r-y and nothing seems to move very quickly to or from here where Aust Post is involved :lol:
As far as those solar panels being factory installed, doubtful. The factory put wiring in the roof under a connection box but all accessories are usually fitted by the dealer. That way Jayco get to wipe their hands of any weight problems caused by adding the accessories and any water leaks they can pass off as being caused by accessories being fitted. The other reason is the additional skill sets being required over and above the assembly line RV construction can't be justified at the factory level and gives the dealer an additional profit potential by upselling each sale.
One thing you can be confident about, the wiring is enough for maybe 160w of solar at the most and runs from one end of the van to the other and back again in most cases resulting a serious voltage drop.

T1 Terry

Tony Bev · Guru

Hi Terry

Not trying to hijack the post

The diodes you sent to me, took about one week to arrive

I sent the two spares you gave me to, Ian
200 kilometres away

Handed them over the counter of the main Post Office in Bunbury, a large regional centre, 9am Friday morning
Ian received them, in a suburb of a city, Monday afternoon

Therefore one week from the countryside of SA, was probably quick going