Solar schematic, do I have this drawn up correctly?

[BigAl]

can someone tell me what the largest size dc-dc charger would be that works with stock tow vehicle wiring ? As in a ballpark figure.

[OrangeCrush]

Originally Posted by BigAl

can someone tell me what the largest size dc-dc charger would be that works with stock tow vehicle wiring ? As in a ballpark figure.

My analysis says Victron Orion 12/12 18 amp should work with F250 factory wire 10 AWG and 30 amp fuse. Have not tried it yet so others with test results may know better than me.

[AlIslander]

Originally Posted by MNThunter

Yes I’ve heard great things about AM solar but also interested in what else is out there. Did Zamp offer to sell the baseplates?

Yes they agreed to send them. It was a big deal for me because I want to be able to remove the panels when I need to and without the baseplates the panels will be installed permanently without hardly any surface area.

[bmklawt]

Can I use this ATO fuse holder from Victron on the Lynx Distributor for my DC to DC charger 12/12-18, it is mentioned in there "Battery Management System BMS 12/200" manual. What fuse size do I use for a 12/12-18 DC to DC charger using my current 12 AWG 7 pin wiring.

[BigAl]

Hi Bruce, If I remember correctly the lynx distributor uses Mega fuses. The smallest Mega fuse I have been able to find is a 40 amp one. I am contemplating the same setup and think to use a smaller fuse it will have to be outside the distributor in a separate fuse holder.
Al

[BigAl]

Bruce, did you change your dc-dc charger size to not overload the wire size that exists from your alternator? I am trying to decide that as well.
Al

[MNThunter]

Originally Posted by OrangeCrush

Sorry for late reply but been busing wiring up my latest project. Will post pics when I am done.

I have only done a quick look at your schematic and here are a few comments.

Thanks Robert!

1) You really should add a fuse between you portable panel and the battery. If I recall, the Zamp port had one in line so maybe it's there just not on your schematic.

Will do, the portable has a fuse and the port also has a fuse I will add to the schematic.


2). If you are putting those batteries outside and plan on any cold weather you may want to add a switched connection to the heaters. The reason for a switch is so the heaters don't run in the cold when you are not needing them.

Good point. The wiring came with the batteries.

3). I understand not using the Lynx distributor. It is huge and since 40 amp fuses are minimum it is better for larger installs than yours.

4). I don't see a temperature sensor. If you add one to your BMV (I assume it is 712) then it will bluetooth the temperature to your MPPT controller so it can to adjust charge profile over temperature. More importnat with AGM but worst case it a nice way to check outside temperature.

Thanks for this, I didn’t realize I should add this but looks like a simple $30 addition to the BMV 712

5). I don't see an inverter. Is that part of "factory wiring". If so you may be surprised to find out there are separate larger gauge cables to the battery for it. Devil is in the detail here so you might find some surprises when you dig in which is OK.

This was one I really wished I’d known more about early on when we ordered (took 12 months to get our camper). The Bambi doesn’t have an inverter, so we were going to add one. The only thing we really want to charge is our phones and it does come with some USB ports so we realized we’re all set. If that changes I’ve scoped in a 1200w. The other thing to add for anyone reading is the stock converter has a switch between Lead Acid and Lithium. It’s right on the electrical panel and super simple.

+1 on AM solar mounts. Pricy but they give you some adjustability for roof slope. If you use VHB make sure it is the right kind and properly installed with Sikaflex 221 on top.

What is better for roof slope? Perpendicular to the ground or angled with the roof slope? I’ve seen the following VHB tales mentioned in threads 4941, 4950, and 5952, is one preferred for airstream roofs?

Thanks!

[bmklawt]

Victron make a ATO fuse holder the will fit in a Lynx Distributor.
I am going to use a Victron Energy Orion-Tr Smart 12/12-Volt 18 amp 220-Watt DC-DC Charger, Isolated (Bluetooth) that is what has been recommend by forum members, Battle Born and Victron.
Two different techs at Battle Born both told me I could hook up my existing power, 12awg, from the 7 pin trailer plug into the solar system without a DC to DC charger and I would in no way harm any of the solar components, truck battery or alternator, one tech said this is a myth they are trying to dispel, that the truck wouldn't let the solar system draw to much current or something like that, everyone else says I absolutely need a DC to DC charger so I am putting one in

[BigAl]

good to know about the fuse holder. Solves a few issues. My only concern on the dc-dc charger is the length of wire from the alternator to the dc-dc charger which will be in my trailer. It is about 27 feet. That seems to be a long run for 18 amps. I am not an electrical engineer so I was looking at a chart for cables.
Al
Edit. I believe my truck has 10 gauge wire.

[BigAl]

I have had my setup in for 8 years with a solar charger and the stock 7-pin setup and have had no problems. I believe the reason to put in a dc-dc charger is to keep the voltage up so it will actually charge the batteries. Without it there is often enough voltage drop that you get no charge going to the trailer.
Al

[bmklawt]

I am assuming my truck 7 pin power is 10AWG it is fused at 30amp the trailer wiring is 12AWG, I have enough of the interior wall panels out that I am going to run 6AWG wire from the 7 pin back to the DC to DC charger. If I ever upgrade the truck with 6AWG wire I'll add an Anderson connector for the DC to DC charger.

[trsvax]

I'm not an EE either but here is my take

10 awg will take 18 amps with perhaps 20 watts lost

6 awg will take 18 amps with perhaps 10 watts lost

Either way the battery will be charged but 10 awg would take slightly longer. If you are not pushing 18 amps into the battery loss will be less.

Upgrading from 10 awg to 6 awg is a cost benefit tradeoff.

I know what I would do. Others might come to a different conclusion. I think either is OK others might not.

FYI: I decided the solar could change the battery while diving and did not connect the charge wire when I had to replace the 7 pin wire on the trailer.

[OrangeCrush]

Most 7 pin connectors use 12 awg for everything except the charge line and ground which are 10 awg. That is what your Airstream Bargman cable should be. You'll have to check your TV. Asuming 10 gauge wire for charge/ground and 90% boost efficiency a 27ft round trip will result in a voltage drop of:

2*27ft * .001ohms * 18amps/0.9 efficiency = 1.08V drop.

Assuming your alternator is putting out 13.5 volts or so, at 18 amps you will still be at over 12V which is well above the Orion 7V minimum. So the Orion will take that 12V and boost it up to 14.6V so those Lithium batteries will be able to take that 18 amps. This example illustrates how I believe an 18amp DC-DC charger with stock charge line should be good for an 18 amp continuous charge while driving. It also illustrates why you want a DC-DC converter as you can see without it you would not have adequate voltage to charge either AGM or Lithium.

[BigAl]

Thank-you very much for such a clear explanation of how it all relates.
Al

[BigAl]

anybody have recommendations on crimping tools for battery cables etc. I am going to need to fabricate quite a few.
Al

[richard5933]

Originally Posted by BigAl

anybody have recommendations on crimping tools for battery cables etc. I am going to need to fabricate quite a few.
Al

I've got one like this: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

This particular one is not available, but there are many just like it. Mount the non-moving part to a board and clamp it to your workbench. These are great for putting a thorough and even crimp on the larger lugs - I've used it for everything from 6 ga. lugs on up to 4/0 lugs, and it produces results better than any hammer-smacked crimping tool can do.

[OrangeCrush]

Originally Posted by BigAl

anybody have recommendations on crimping tools for battery cables etc. I am going to need to fabricate quite a few.
Al

I second richard5933's recommendation. I got the Temco version which is over priced in my opinion and probably same as all the other 16 ton crimpers. I highly recommend Del City for 4/0 lugs. They are really heavy and they ship fast.

[Glen Carter]

Originally Posted by OrangeCrush

I second richard5933's recommendation. I got the Temco version which is over priced in my opinion and probably same as all the other 16 ton crimpers. I highly recommend Del City for 4/0 lugs. They are really heavy and they ship fast.

I went with the Temco too!

https://temcoindustrial.com/th0005-v...h-32-die-sets/

[C.Martin]

Originally Posted by MNThunter

4). I don't see a temperature sensor. If you add one to your BMV (I assume it is 712) then it will bluetooth the temperature to your MPPT controller so it can to adjust charge profile over temperature. More importnat with AGM but worst case it a nice way to check outside temperature.

Thanks for this, I didn’t realize I should add this but looks like a simple $30 addition to the BMV 712

!

I would check with BattleBorn.

To my knowledge…there isn’t a Lithium Battery that benefits from applying temperature coefficients to the charge parameters that you program for Lithium.

If they do..it’s news to me.

It could till be a good idea in a Victron System to add the Victron temperature sense/ or BMV temperature accessory… because their controllers allow you to set the temperature coefficient. You can set it to zero. The sensor will allow you to monitor temperature as far as when to turn on the heating circuit..or with the BMV-712…you can use the relay to trigger a warning piezo horn/light.

The Magnum Inverter has no way to alter temp coefficient. I believe it best to remove the ME-TP accessory. The built-in BMS on the battleborns are probably happier with the recommended charge parameters being constant…and not altered by the temp sense.

[OrangeCrush]

Originally Posted by C.Martin

I would check with BattleBorn.

To my knowledge…there isn’t a Lithium Battery that benefits from applying temperature coefficients to the charge parameters that you program for Lithium.

If they do..it’s news to me.

It could till be a good idea in a Victron System to add the Victron temperature sense/ or BMV temperature accessory… because their controllers allow you to set the temperature coefficient. You can set it to zero. The sensor will allow you to monitor temperature as far as when to turn on the heating circuit..or with the BMV-712…you can use the relay to trigger a warning piezo horn/light.

The Magnum Inverter has no way to alter temp coefficient. I believe it best to remove the ME-TP accessory. The built-in BMS on the battleborns are probably happier with the recommended charge parameters being constant…and not altered by the temp sense.

You are right on BattleBorn not needing temperature compensation. Still nice to have a temperature sensor, especially if they are outside. When we had AGM outside we needed it for charge compensation but we enjoyed having it as an easy way to see what the outside temperature was on our phone.