Solar The Solar Panel Thread

Boots in Action

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Actually it was wired correctly. Nothing gets connected to the load outputs, that is designed for a 12v output only, not for charging.

To see the amp reading on the topray you just press the black button a couple of times and it cycles between battery voltage and current.


Thanks @Bellbirdweb and @Eddii for your prompt replies. Not knowing this type of controller, it looks like I may have gone off 'half cocked"!! A couple of things I have noticed are: there is no black button on front of TPS 1230 model, only 2 red buttons, one on left marked with a red triangle and the other shows two light bulbs (one illuminated and the other not so) with a double pointed arrow between them. I will have a further look at the original instructions my Daughter has as I am sure it speaks about amp hours used. That would have to come from the Pos and neg terminals on the Setec distribution system. When I had a PWM solar controller Power Tech 30A) the load terminals were connected to the Pos and Neg output terminals on the Setec distribution box and it gave me a readout of amp hours used for the day, the day before and the day before that. The MPPT controller I now have gives both amp hours consumed and amp hours into battery on continuous logging. I zero the readouts every morning so i know what happened and start again. I thought the Topray was similar. I will get back after looking at instructions. Thanks again. @Glen Bundesen , take note of what others say for the time being please.
 

Bellbirdweb

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Jan 24, 2014
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Thanks @Bellbirdweb and @Eddii for your prompt replies. Not knowing this type of controller, it looks like I may have gone off 'half cocked"!! A couple of things I have noticed are: there is no black button on front of TPS 1230 model, only 2 red buttons, one on left marked with a red triangle and the other shows two light bulbs (one illuminated and the other not so) with a double pointed arrow between them. I will have a further look at the original instructions my Daughter has as I am sure it speaks about amp hours used. That would have to come from the Pos and neg terminals on the Setec distribution system. When I had a PWM solar controller Power Tech 30A) the load terminals were connected to the Pos and Neg output terminals on the Setec distribution box and it gave me a readout of amp hours used for the day, the day before and the day before that. The MPPT controller I now have gives both amp hours consumed and amp hours into battery on continuous logging. I zero the readouts every morning so i know what happened and start again. I thought the Topray was similar. I will get back after looking at instructions. Thanks again. @Glen Bundesen , take note of what others say for the time being please.
@Boots in Action, it’s been a while since I played with my TPS1230 having since moved to my eperver MPPT. The buttons are red not black.

The one with the triangle toggles between amps and volts. It doesn’t show any accumulative figures, only the live current.

The one with the globe symbol is the on/off switch to control the load output.
 

Boots in Action

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Mar 13, 2017
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Actually it was wired correctly. Nothing gets connected to the load outputs, that is designed for a 12v output only, not for charging.

To see the amp reading on the topray you just press the black button a couple of times and it cycles between battery voltage and current.

Hi @Bellbirdweb , @Eddii and @Glen Bundesen , thank you all for the responses. Firstly, the Jayco connection may be correct but it is INCOMPLETE if you wish to use the full facilities of this very basic and crude controller. It may give a continuous display of battery voltage or if toggled, will also display amperage going into battery, but to obtain amperage OUT from battery to load is a messy arrangement indeed. There are lots of better and more easily operated controllers on the market for about the same price in PWM. It would seem that this controller would only be useful for those with more sophisticated monitoring systems to back up the limited info it provides eg. Drifter panel control. When I went back into some of the previous posts on this type of controller, there were a few problems with not showing charging and a lack of info. Indeed, one member discarded the Topray TPS 1230 and replaced it with a Powertech PV controller which gives a lot more detail - albeit at twice the price!! I will be replacing my Daughter's controller with my no longer wanted Powertech 20A ( I now use my MPPT controller) and teach them how to read it properly. I see that at the moment the Powertech is around $190.00 which is expensive, particularly when I can buy a LD MPPT 30A controller $50.00 less than that and has heaps of readouts available on screen including continual logging and recording!!

The following site gives FULL details of what you have to do to get all the readouts on the TOPRAYSOLAR TPS 1230:

https://www.caravansplus.com.au/pdf/solar_reg.pdf
@Glen Bundesen , after reading the above site, if you wish to know what current is going to the load, you will have to use the load terminals and connect them to the ve pos and ve negative output terminals on you Setec controller at the fuse panel. If in doubt, refer to Setec manual.
 

Bellbirdweb

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Jan 24, 2014
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Sorry @Bellbirdweb , not correct. Check out web- site listed in recent reply. No wonder I would not have one of these!!
That is only correct if you want to power the load from solar ONLY, which is not how the vans are wired.

The 12v loads are all derived from the battery, and the solar is only used to charge the battery, so I stand by what I have said.

You are correct in stating that you require another system to monitor the load of the system, hence the Drifter panel and shunt arrangement.

Given these Jayco fitted controllers are $35.00 each, I'm impressed they do as well as they do, but they are very basic.
 

Boots in Action

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Mar 13, 2017
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That is only correct if you want to power the load from solar ONLY, which is not how the vans are wired.

The 12v loads are all derived from the battery, and the solar is only used to charge the battery, so I stand by what I have said.

You are correct in stating that you require another system to monitor the load of the system, hence the Drifter panel and shunt arrangement.

Given these Jayco fitted controllers are $35.00 each, I'm impressed they do as well as they do, but they are very basic.

Hello again @Bellbirdweb , first of all, my humblest apologies - foot in mouth disease I am afraid. Could not comprehend what you were saying, so went back to the site for this panel and then saw that the display is Battery Voltage (volts) , then BATTERY OUTPUT to LOAD (Amps) , and then Solar Power Input (Amps). If my understanding is correct, then there is very little reason to use the right hand button, as you previously said it is mainly to control load on/off and reset if under /over voltage. In fact it duplicates one of the earlier displays too!! Is that correct?? Therefore, the only thing one would not have if load wires were not connected was the ability to turn load on or off. I hope this clarifies the matter for @Glen Bundesen , as I do not want to confuse him. Obviously with the Powertech controller I am going to install in daughter's van, I will need to connect up the Load wires to the Setec battery output terminals.
Incidentally, the Topray controller is selling for over $85.00 on Ebay, so Jayco are getting them at a good price. Not good value IMHO, but I suppose it all depends on how much surveillance one wants to keep or understand on battery management. Thanks again.
 

Bellbirdweb

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Jan 24, 2014
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Hello again @Bellbirdweb , first of all, my humblest apologies - foot in mouth disease I am afraid. Could not comprehend what you were saying, so went back to the site for this panel and then saw that the display is Battery Voltage (volts) , then BATTERY OUTPUT to LOAD (Amps) , and then Solar Power Input (Amps). If my understanding is correct, then there is very little reason to use the right hand button, as you previously said it is mainly to control load on/off and reset if under /over voltage. In fact it duplicates one of the earlier displays too!! Is that correct?? Therefore, the only thing one would not have if load wires were not connected was the ability to turn load on or off. I hope this clarifies the matter for @Glen Bundesen , as I do not want to confuse him. Obviously with the Powertech controller I am going to install in daughter's van, I will need to connect up the Load wires to the Setec battery output terminals.
Incidentally, the Topray controller is selling for over $85.00 on Ebay, so Jayco are getting them at a good price. Not good value IMHO, but I suppose it all depends on how much surveillance one wants to keep or understand on battery management. Thanks again.
No need to apologise @Boots in Action, this is a learning and sharing forum and we are all doing that with these posts.

I’m still a litttle confused as to why you would connect the load terminals on the powertech controller to the setec battery output terminals.

If I understand correctly, the batter output terminal would be to supply power from the battery via the setec to Power 12 devices.

The load terminals on the controller, be it Topray, Powertech or even my Eperver are to supply 12v to supply power to devices but coming from the door directly.

If you connect the load and battery output terminals together I suspect you’ll see smoke.
 

mikerezny

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Sep 11, 2016
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Hi,
the issue is that the solar controller and the Setec have both been designed to be the MASTER controller. In my opinion, it makes much more sense to keep the Setec as the master controller. You then get a multi-stage 240V battery charger, a 240V to 12V power supply, ability to charge via the AUX input from the tug alternator, fuse distribution system, low voltage disconnect, and on the Setec III, the ability to completely isolate the battery from all loads.

You then add a roof mounted solar panel/controller to the system by connecting the battery terminals of the solar controller directly to the battery via an inline fuse. Keep the wiring from the controller to the battery as short as possible. You do not connect anything to the load terminals of the solar controller. In this way the solar controller is NOT the master controller and becomes the SECONDARY controller.

In more sophisticated controllers, you will be able to measure battery voltage, instantaneous current coming from the panels to the battery, and accumulated charge and possibly many other things.

Battery state of charge can (SOC) only be measured with no load on the battery, and some time after any charge has been put into the battery. I have found the best time to measure SOC when off grid is first thing in the morning. If you have a Setec III, then also switch the battery off to ensure there really is no load. You will need to print off a table or chart for your particular battery type which shows no load voltage against % SOC. AGM, GELs, and normal Lead Acid batteries differ in this regard.

Taking the SOC of the battery, you can then determine how many Ah must be generated during the day to fully restore the SOC to 100%. You need to add a bit more for efficiency losses (i.e the battery dissipates heat when it is charged and discharged). I would suggest adding about 10%. With time you will generally get a feel for how much power you are consuming per day.

After this you can get more complex by adding portable solar panels, a DC-DC charger to get higher charge rates to the van battery from the tug.

If contemplating putting charge into the van battery from a portable generator, I would strongly suggest not using the Setec but getting a more heavy duty multi-stage charger that will deliver more current. The reason is to charge the batteries faster, use less fuel, and annoy fellow yor campers much less.

As an example, assume a 100Ah battery and a Setec ST20 has a MAX charge rate of 10A. So, the maximum power going into the battery from the generator will be approximately 140W. (14V x 10A). Drwaing only 140W is tot really an efficient use of a 2kW generator! At 10A and a battery that is down to 50%SOC, it will take way longer than 5 hours to pump the 50Ah needed to fully charge a 100Ah battery. The reason it will be way longer is that the last part of the charging cycle to get the battery back to 100% will be done in float mode which will be charging at currents much less than 10A.

Now, a Ritar 100Ah battery has a maximum charging current of 20A. So, getting a good 20A multi-stage charger will pump twice as much into the battery from the generator. It will charge the battery up twice as quickly and use much less fuel. 20A x 14V is now a more respectable 280W load on your 2kW generator.

If you have multiple batteries, get an even bigger charger. i.e a 40A charger for 2 x 100Ah batteries.

If you have a solar controller that does not output battery voltage, instantaneous charge, and accumulated charge, invest $15 or so on buying one of these on eBay. Note that these will only measure current on ONE direction. So they are good for measuring solar panel output but not good for measuring charge into and discharge out of a battery.

cheers
Mike
image1.jpeg
 

Eddii

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Great explanation @mikerezny :) I noticed that if you have an external solar panels plugged directly to the house batteries and solar produced from house controller they seem to be “fighting” each other. I have 150w/Topray PWM in house setup plus 200w/xxxPWM controller folding panels charging 2 x 100ah ritar gel batteries and the don’t seem to be efficiently working together, they both jack up the voltage which puts both controllers in float mode and slows the chargers down. I’ll be replacing the Topray today with Victron energy smart controller MPPT and move that controller to the folding panels so I can really see much more status via mobile app and also see how much the folding panels are charging as well . Then I’ll do more experiments like introducing the folding panels to see how much the house controller pulls back.
 

Boots in Action

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Mar 13, 2017
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No need to apologise @Boots in Action, this is a learning and sharing forum and we are all doing that with these posts.

I’m still a litttle confused as to why you would connect the load terminals on the powertech controller to the setec battery output terminals.

If I understand correctly, the batter output terminal would be to supply power from the battery via the setec to Power 12 devices.

The load terminals on the controller, be it Topray, Powertech or even my Eperver are to supply 12v to supply power to devices but coming from the door directly.

If you connect the load and battery output terminals together I suspect you’ll see smoke.

Hi again @Bellbirdweb , thanks for your kind words of encouragement to this "upstart tech head". Sometimes I need pulling into line!!!
The matter about connecting the load terminals to the solar controller is I think a very important one. As you are no doubt aware, most of the better controllers incl your Epever and my LD MPPT controller have "user adjustable" settings for LVD and LVR (amongst others) to allow us to set our own levels of protection for our very important and expensive AGM or GEL battery. Unfortunately, a lot of the cheaper solar controllers have a fixed setting for both, set at factory, which may or may not be suitable - most are not!! And to make matters worse, were you aware that on a Setec (mine at least), has a fixed setting of 10.00V plus/minus 0.2V for LVD?? (refer specs manual) At that voltage, the battery would be "stuffed" and probably beyond proper recovery. It certainly did NOT protect my Daughter's battery!!! And I do not want my setting THAT LOW. (refer SOC chart).
The advantage of connecting the LOAD wiring to the solar controller, means that the solar controller senses the low voltage setting BEFORE the SETEC does, and disconnects the load at whatever setting is on the solar controller (fixed or manually set). I note that on the Topray, the LVD is 10.7v plus/minus 0.4 , which to my mind is far too low, but better than depending on the Setec at 10.00 volts!! All or most of the members on this forum are, or should be aware of the need to keep battery charge state above 50% if possible and definitely try to use no more than 70% if full recovery of battery is to be achieved. I have included a SOC table once again for AGM batteries.
But I digress. If the load wiring is NOT connected through the solar controller, the LVD defaults to the Setec at 10.00 volts - far too late!!! If the load wires are connected through the solar controller ( load connection), that setting takes precedence much, much earlier. For this to operate, those wires must be connected, otherwise the solar controller is unable to sense the low voltage and operate disconnection of load/s.

I have the LVD on my MPPT solar controller set at 11.80 volts (30% remaining capacity) and LVR at 12.2 volts (60% capacity available). The LVD setting is just before things are dropping into oblivion and the "no go area" to protect my battery. If the voltage was to drop into this zone because of very heavy short term demand with load and disconnection occurred, I can always reduce load/s, and the reconnection will be made automatically as voltage recovers, even without charging.

I have just finished working on Daughter's van and NO SMOKE!! The line +ve comes off the Battery Output in the Setec distribution panel at fuse panel, and goes to the battery disconnect switch. I disconnected the wire from the other side of this battery switch and ran a direct line to the Pos Load connection on solar controller. The wire from the Neg connector on the controller returns to join the wire disconnected from back of battery switch, to place the load/s in series with the controller. The Neg line (return after handling the various loads) remains connected to the battery -ve to complete the circuit.
Hope you can understand this okay. With a Drifter panel, all this may be of little use or interest, but perhaps there are others who may find this valuable in avoiding expensive damage to battery. I look forward to you comments. Cheers.
 

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Boots in Action

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Unfortunately, Jayco never connects those Solar controller load output terminals to anything because they all go to Setec. Also, controller only has max 30A load. I'm pretty sure no other caravan manufacturer uses these units to give the full load status. You'll have to buy a unit and fit it at the battery terminals to get the full consumption.

Hi @Eddii , have a read of my latest posting and have a think about your Setec letting battery voltage drop to 10.00 plus/minus 0.2 volt before alarm or disconnecting load. There are reasons for having LVD on solar panels, but most of the cheaper ones are too low eg Topray is 10.7 plus/minus 0.4 v. Tread your own path.
 

Boots in Action

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Mar 13, 2017
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Great explanation @mikerezny :) I noticed that if you have an external solar panels plugged directly to the house batteries and solar produced from house controller they seem to be “fighting” each other. I have 150w/Topray PWM in house setup plus 200w/xxxPWM controller folding panels charging 2 x 100ah ritar gel batteries and the don’t seem to be efficiently working together, they both jack up the voltage which puts both controllers in float mode and slows the chargers down. I’ll be replacing the Topray today with Victron energy smart controller MPPT and move that controller to the folding panels so I can really see much more status via mobile app and also see how much the folding panels are charging as well . Then I’ll do more experiments like introducing the folding panels to see how much the house controller pulls back.

Hi again @Eddii , this situation has been covered in depth some time before. Perhaps you may have missed it. Go back on this post for Solar and have a read of post # 928. Whilst there has been some disagreement by some members, it still remains a good topic to discuss. @mikerezny has said before that to keep it simple and get the max out of what you have, purchase a good MPPT controller (my LD MPPT controller cost less than $150.00, does not need a separate panel or computer as ALL settings can be made on controller). Then, instead of having two controllers "fighting" each other, connect another line from outside of van to same solar input terminals as roof solar to MPPT controller (house control) with Anderson plug on outside. Bypass the controllers on back of portable panels, there is a posting on this too) and connect the portable panels by cable with Anderson plug to external plug on van. The solar on the roof and any portable panels deployed (if any) are then connected in parallel and controlled by the very efficient MPPT controller. In bypassing the controllers on back of portable panels, you do not lose the ability to use them is the normal way to charge car battery etc as they still have their own controller available.
 

Boots in Action

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Hi Boots
Just fitting a TopRaySolar and was wondering what needs to go into the LOAD side. Do I just run another twin from the battery to the "Load" terminals and leave the existing wires/circuits coming straight from the battery?

Hello @Glen Bundesen , no doubt you have been following the latest on the TOPRAY controller, its virtues and faults. I have just completed another post on why I think (my OWN ideas!!) that the load wires should be connected to the solar controller. Have a read and make your own decisions. Note that even if connected to the load terminals, Low Voltage Disconnect for the TopRay is a very low 10.7 volts (give or take 0.4 volt) and if you have a Setec distribution control, its fixed LVD setting is an abysmal 10.00 volts plus or minus 0.2 volts. Crazy - far too low to protect battery from permanent damage - even a great AGM! Tread your own path. But better to have a higher LVD than a lower one. I am doing a wiring diagram for another member to help with you connections if needed. We do not want any smoke and flame, do we??
 
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Boots in Action

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Interesting fine there @Boots in Action, I shall check my Setec then. Thanks. I’m a bit confused with your wiring though, can you please put out a rough diagram if possible. I’m not quite sure how it works in series.

Yes @Eddii , a bit disturbing when one does the research. Even I did not know until Daughter's van battery failed and did not sound any alarm until power disconnected with only two LED lights on and a small DVD player - less than 2 amp draw total!! But then they were only checking voltage during the day with NO Load and the voltage on their TopRay was showing 12.56 volts. Put a light load on it, and it dropped to below 11.6 volts in seconds and continued to drop to 10.6 volts and still had not disconnected!!! I will get rough drawing to you asap. With a good MPPT controller, YOU can set the levels YOU want, as mostly they are "user adjustable".
 

mikerezny

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Sep 11, 2016
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Hi @Boots in Action,
I am unsure about connecting the van load to the load terminals of a solar controller.
My main question is that if this is done then how does one charge the battery from 240V via the Setec unit? How does one charge the battery from the tug via the AUX input (assuming one does not want to go down the path of a DC-DC charger)?

My next question concerns the solar controllers ability to handle the total current drawn from the battery to supply the van.
Contrived example: if one buys a 10A solar controller to assist in keeping the battery charged, but the van load occasionally requires 20A to say power an inverter for a few minutes. It seems that in choosing a solar controller, one would have to take into account the solar panel size as well as the maximum anticipated load.

I understand the importance of having an adjustable LVD, but there is also a more frequent possibility that inverters of 1000W or more will be wired directly to the battery via very heavy gauge wire and there is no possibility of expecting the Setec or a solar controller to protect the battery in this case.

Whilst LVD is a great backup in case something is inadvertently switched on, in my opinion, it should not be used instead of gaining a thorough understanding of the 12V systems installed in vans which includes knowing SOC every morning and ensuring, whenever possible, that full recovery is achieved by the end of each day. Once that is achieved, it should be most unlikely that LVD will ever be activated and whether it is set at 10V or whatever, will not be all that important.

With the quite complex 12V systems installed in tugs and vans and the myriad of possible ways of connecting the various components together to suit the wide-ranging requirements of users, it is clear that there are, at this point in time, no foolproof, perfect systems. Every solution has its pros and cons and requires a lot of thought to understand our individual requirements, expected performance, and the evaluation of possible solutions, quite often with some degrees of compromise.

On a more optimistic note. Although this thread does oscillate back and forth over many of the issues in this area, it is and I hope always will be a great source of information and assistance allowing everyone to get a better understanding of this quite complex subject. There is usually no single solution, but in discussing various solutions to each problem given by people with varying requirements and experiences, we all gain valuable insights.

Now, off to the fridge to get a cider.....and set up my stool so I can admire my new shiny cost-free AL-KO corner steadies and contemplate what extra I can load into the van since the new jacks weigh, in total, 1.2kg less than the old longer ones.

Enjoy what is left of the weekend, wherever you are.

cheers
Mike
 
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Boots in Action

Well-Known Member
Mar 13, 2017
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Ferny Grove, Queensland
Hi,
the issue is that the solar controller and the Setec have both been designed to be the MASTER controller. In my opinion, it makes much more sense to keep the Setec as the master controller. You then get a multi-stage 240V battery charger, a 240V to 12V power supply, ability to charge via the AUX input from the tug alternator, fuse distribution system, low voltage disconnect, and on the Setec III, the ability to completely isolate the battery from all loads.

You then add a roof mounted solar panel/controller to the system by connecting the battery terminals of the solar controller directly to the battery via an inline fuse. Keep the wiring from the controller to the battery as short as possible. You do not connect anything to the load terminals of the solar controller. In this way the solar controller is NOT the master controller and becomes the SECONDARY controller.

In more sophisticated controllers, you will be able to measure battery voltage, instantaneous current coming from the panels to the battery, and accumulated charge and possibly many other things.

Battery state of charge can (SOC) only be measured with no load on the battery, and some time after any charge has been put into the battery. I have found the best time to measure SOC when off grid is first thing in the morning. If you have a Setec III, then also switch the battery off to ensure there really is no load. You will need to print off a table or chart for your particular battery type which shows no load voltage against % SOC. AGM, GELs, and normal Lead Acid batteries differ in this regard.

Taking the SOC of the battery, you can then determine how many Ah must be generated during the day to fully restore the SOC to 100%. You need to add a bit more for efficiency losses (i.e the battery dissipates heat when it is charged and discharged). I would suggest adding about 10%. With time you will generally get a feel for how much power you are consuming per day.

After this you can get more complex by adding portable solar panels, a DC-DC charger to get higher charge rates to the van battery from the tug.

If contemplating putting charge into the van battery from a portable generator, I would strongly suggest not using the Setec but getting a more heavy duty multi-stage charger that will deliver more current. The reason is to charge the batteries faster, use less fuel, and annoy fellow yor campers much less.

As an example, assume a 100Ah battery and a Setec ST20 has a MAX charge rate of 10A. So, the maximum power going into the battery from the generator will be approximately 140W. (14V x 10A). Drwaing only 140W is tot really an efficient use of a 2kW generator! At 10A and a battery that is down to 50%SOC, it will take way longer than 5 hours to pump the 50Ah needed to fully charge a 100Ah battery. The reason it will be way longer is that the last part of the charging cycle to get the battery back to 100% will be done in float mode which will be charging at currents much less than 10A.

Now, a Ritar 100Ah battery has a maximum charging current of 20A. So, getting a good 20A multi-stage charger will pump twice as much into the battery from the generator. It will charge the battery up twice as quickly and use much less fuel. 20A x 14V is now a more respectable 280W load on your 2kW generator.

If you have multiple batteries, get an even bigger charger. i.e a 40A charger for 2 x 100Ah batteries.

If you have a solar controller that does not output battery voltage, instantaneous charge, and accumulated charge, invest $15 or so on buying one of these on eBay. Note that these will only measure current on ONE direction. So they are good for measuring solar panel output but not good for measuring charge into and discharge out of a battery.

cheers
Mike
View attachment 60685
Hi Mike @mikerezny , I am in agreement with your first paragraph, except for the Master Controller. All functions still operate as you stated even if the Load wiring goes through the solar controller. The last two sentences of the second are not correct in my opinion. Firstly, solar input is connected across the battery terminals and has nothing to do with the Setec controller. The Setec controller is mainly for distribution of power to different areas including various other charging options. It does not control voltage or current from solar, as this is the solar controller's task. The Setec does have other functions amongst which is LVD and LVR and 240 volt charging at various stages of battery use. However, if all loads go through the solar controller, it has first dibs at monitoring/controlling the state of battery voltage ie LVD and LVR . So instead of being a slave to the Setec in voltage awareness, it provides an early warning system BEFORE the Setec can do so. In view of the specs on the Setec manual of 10.00 volt LVD setting, I would not want to leave it to the Setec to decide my battery 's future.
The rest of your post is the "usual good stuff".

Getting cold up here at night. Bring some warm clothes when you come.
 
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Boots in Action

Well-Known Member
Mar 13, 2017
2,054
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113
Ferny Grove, Queensland
Hi @Boots in Action,
I am unsure about connecting the van load to the load terminals of a solar controller.
My main question is that if this is done then how does one charge the battery from 240V via the Setec unit? How does one charge the battery from the tug via the AUX input (assuming one does not want to go down the path of a DC-DC charger)?

My next question concerns the solar controllers ability to handle the total current drawn from the battery to supply the van.
Contrived example: if one buys a 10A solar controller to assist in keeping the battery charged, but the van load occasionally requires 20A to say power an inverter for a few minutes. It seems that in choosing a solar controller, one would have to take into account the solar panel size as well as the maximum anticipated load.

I understand the importance of having an adjustable LVD, but there is also a more frequent possibility that inverters of 1000W or more will be wired directly to the battery via very heavy gauge wire and there is no possibility of expecting the Setec or a solar controller to protect the battery in this case.

Whilst LVD is a great backup in case something is inadvertently switched on, in my opinion, it should not be used instead of gaining a thorough understanding of the 12V systems installed in vans which includes knowing SOC every morning and ensuring, whenever possible, that full recovery is achieved by the end of each day. Once that is achieved, it should be most unlikely that LVD will ever be activated and whether it is set at 10V or whatever, will not be all that important.

With the quite complex 12V systems installed in tugs and vans and the myriad of possible ways of connecting the various components together to suit the wide-ranging requirements of users, it is clear that there are, at this point in time, no foolproof, perfect systems. Every solution has its pros and cons and requires a lot of thought to understand our individual requirements, expected performance, and the evaluation of possible solutions, quite often with some degrees of compromise.

On a more optimistic note. Although this thread does oscillate back and forth over many of the issues in this area, it is and I hope always will be a great source of information and assistance allowing everyone to get a better understanding of this quite complex subject. There is usually no single solution, but in discussing various solutions to each problem given by people with varying requirements and experiences, we all gain valuable insights.

Now, off to the fridge to get a cider.....and set up my stool so I can admire my new shiny cost-free AL-KO corner steadies and contemplate what extra I can load into the van since the new jacks weigh, in total, 1.2kg less than the old longer ones.

Enjoy what is left of the weekend, wherever you are.

cheers
Mike
Hi @mikerezny , you make some good points there. But some of them are easily answered.
para 1. I do not think the Setec would see the battery charging as a "LOAD" as current/voltage would be directed across battery terminals and not through the various fuse outlets for various loads. If using/obtaining power from tug,, fridge power is normally NOT connected through battery in van. For maintaining a reasonable voltage to van battery (and that is all it would be doing - 14.4 vehicle voltage minus .7 volt through power diode less any other losses) is the reason for not being able to CHARGE van battery - just reaches float voltage , so in reality NOT charging up a lower voltage in battery! and would not be seen as a load. Other items running in van WOULD be seen as a load, but would not affect charging I believe. Not tested by me and subject to correction by advanced "Tech Heads"!
Para 2. Good point if low power Solar Controller. However, most solar controller instructions advise to connect "high power devices" directly across the battery terminals, so that that high current draw would not be seen as a load and only a sharp voltage drop would be seen on controller. Incidently, my Setec controller has 8 fused outlets @ 10 amps each. BUT, the total output from these outlets is limited to 25 amps by fuse and over current protection.
Para 3. Agreed, but see previous post regarding auto reconnect if very large current drain drop causes large voltage drop.
Para 4. One has to work on the lowest common denominator as a lot of people with very limited knowledge (my daughter was until now!!) need to have some sort of fall back - even if it is too late!! The SOC is important, but some sort of light load after checking voltage will determine whether just a "surface charge" or whether the battery has no guts and cannot carry any sort of load. Talk to you more about this and the not so smart "smart charger" when faced with this dilemma.
Para 5 . Agreed entirely. It is far more complex and diverse than most realize.
Para 6. With your help, this will continue I hope.

I hope this answers some or most of your points, but I am sure we will have further discussions on this subject. Thanks for raising some of those issues.
 
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