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ChrisnPatty · 08-07-2019, 02:28 PM

I know this specific question has been addressed on these forums, but I cannot find the answer, so please pardon the repeat.

I will be installing the Victron 712 in my 22FB as part of my upgrade to a Lithium Battery. Other than switching my converter to a Lithium compatible unit, I plan to keep everything else very simple.

I have a portable Zamp solar panel which plugs into an external fitting with two wires that currently run directly to the battery terminals.

I believe I recall some discussion on this forum regarding the routing of the negative solar wire when installing the Victron shunt.

So, my question is: Can I leave the negative solar wire routed to the battery terminal, or should it be routed to the same connection on the shut as the negative battery lead. If the latter, is it connected on the input or the output side of the shunt?

ROBERT CROSS · 08-07-2019, 05:49 PM

The shunt is wired separately from the solar.
Plug the panel into the external Zamp connector.

Wire them shunt as illustrated.👍

Bob
🇺🇸

waninae39 · 08-07-2019, 06:52 PM

see my post some time ago with my schematic file.
it shows how to install all the victor items with Lion battery

Paprika · 08-07-2019, 07:19 PM

"Can I leave the negative solar wire routed to the battery terminal... ?"

No. In order for the BMV-712 to measure power input/output accurately, all current must pass through the shunt. That includes current from the solar power system.

If you left the solar system's wire on the battery, or on the input side of the shunt, the BMV-712 would not "see" its power input and thus you'd get increasingly false low readings. (I made this mistake once, many years ago.)

So there can only be one connection to the negative battery terminal: the jumper to the input side of the shunt. The solar power wire, along with all the other wires that were on battery's negative terminal, must be moved to the output side of the shunt.

By the way, the Zamp panel's built-in charging controller is almost certainly not designed for use with LiFePO4 batteries. Check this with your battery manufacturer, but if I were you I'd be replacing it with a (much more efficient) Victron Smart Solar 75/15 controller.

ChrisnPatty · 08-07-2019, 08:10 PM

Thanks All. I think I've got it figured out.

The Victron supplied wiring diagram doesn't show a line for power supplied from the solar panels. Thus it was less than helpful.

Waninae39, your diagram is impressive, but much more complicated than my simple set up, with the additional bits and pieces you have included in your system, it was unclear how to directly address the power supply from the solar.

Based on the input from the forum, I conclude I will need to lead the negative supply wire from my solar connection directly to the output side of the Victron shunt.

My Zamp's built in solar controller modual actually is designed to handle LiFePO4 batteries. It can handle them in addition to LTO, Gel, AGM, conventional lead-acid and Calcium batteries.

Thanks again for the advice.

Garfish · 08-12-2019, 09:07 AM

Can you post pix of where you installed the shunt as I am looking to do the same and not sure where negative cables connect to battery inside

PKI · 08-12-2019, 11:02 AM

Garfish - I don't know. Not a 22 owner, but suspect the cables all enter the coach from under the floor in the curb side front corner under the bed. Look to verify as the street side corner is also a possibility.

Believe Waninae39 posted an "as found" picture in one of his examples. May be easiest to just look under the bed as models vary by year.

There is also some difficulty in shunt location as the inverter and converter have separate wiring. The complete battery/solar/inverter/converter/upgrades address that with new wiring runs. The simple BM add-on is more problematic, but lots of folks do it, so you should get a response from one of them.

Some info in the thread about locating shunt in battery box. Believe you posted there.

Good luck with your investigation. The BM does help. Pat

Garfish · 08-12-2019, 10:29 PM

Thanks for the advice. No inverter in sport so will check wire runs

TheSquire · 08-13-2019, 09:29 PM

On a 22fb the 6 gauge wires running from the battery box on the tongue enter on the roadside under the bed. There is a small cover to access the furnace and the bus bars. This is where I mounted the shunt. This is also where the solar pre-wiring is routed. An added bonus is there is an RJ45 wired from this point to just behind the existing meter in the bathroom, so if you want to mount the monitor nearby the existing one, you can use the existing wiring as well.

I also had to rewire the negative leads for the Zamp solar port on the tongue so it is after the shunt (not directly connected to the battery).

Hop this helps.

-Rich

Garfish · 08-13-2019, 10:47 PM

Thanks, Rich

Garfish · 08-21-2019, 08:17 AM

My suitcase solar plugs into 7 pin. Guess that will not work with the the shunt?

TheSquire · 08-22-2019, 07:46 AM

Quote:

Originally Posted by Garfish

My suitcase solar plugs into 7 pin. Guess that will not work with the the shunt?

That should work fine. The 7-pin is wired to the negative bus bar. You just don’t want anything wired directly to the negative battery terminal. Anything that is wired to the negative battery terminal, just move to the other side of the shunt.

uncle_bob · 08-22-2019, 08:29 AM

Hi

Bottom line:

There is no magic trick to mounting the shunt. You have to put in a cable from the battery negative over to the shunt. Everything external moves off of the battery negative. The only thing that goes there is the wire to the shunt.

Second gotcha is that the shunt needs to stay dry. Best approach is to mount it "indoors" in the trailer.

Bob

cru-in · 08-22-2019, 08:42 AM

With your install. Remember you need to isolate the TV batteries (Lead Acid) from the TT batteries (Lithium). Otherwise the TT's LI Battery (with a higher voltage than the Lead Acid in the TV) will bleed charge to charge the TV battery.

Garfish · 09-08-2019, 10:39 AM

Battery to shunt - plan on using existing neg cable from battery into buss bar and move it to shunt, battery side. That cable does not have ring end so guess that means crimp one on? Then new short cable from load side on shunt to neg buss bar. Since no inverter using same gauge.

Pos supply and temp sensor cables - diagram shows connect both to pos side on battery. Can’t run these thru battery cable hole (batteries on tongue) as cables come in too far back from buss bar, not accessible. If i just use the supply one and not temp one can i not connect it to pos buss bar? Otherwise a new hole somewhere out to battery

Help?

pcskier · 09-08-2019, 11:04 AM

Quote:

Originally Posted by Garfish

Battery to shunt - plan on using existing neg cable from battery into buss bar and move it to shunt, battery side. That cable does not have ring end so guess that means crimp one on? Then new short cable from load side on shunt to neg buss bar. Since no inverter using same gauge.

Pos supply and temp sensor cables - diagram shows connect both to pos side on battery. Can’t run these thru battery cable hole (batteries on tongue) as cables come in too far back from buss bar, not accessible. If i just use the supply one and not temp one can i not connect it to pos buss bar? Otherwise a new hole somewhere out to battery
Help?

Not sure what you mean 'cables come in too far back from buss bar, not accessible.' Wire from the tongue typically comes in right up front, and I imagine you've installed the shunt in that area, as close to battery as possible? You should be able to poke a fish hole through the sealant around the wires and pull the power/temp sensor duplex through it. (Do it from outside underneath, pulling the stripped ends through in to the trailer.) It's worth it to get the most from the monitor, but not the end of the world if you don't.

If you decide to just go with power wire, better to put it on the battery side of the use/disconnect switch (look for the LP detector wire, put it in same spot) rather than positive bus. Otherwise monitor will not function when in 'store' mode. It's handy to see it when in 'store' mode to see any phantom draws there might be, and have those draws counted. Again, not a deal killer. The unit draws only .7 ah per month so it's like it's not there as far as power draw.

Garfish · 09-08-2019, 01:49 PM

Was looking in wrong place for the battery cables entry. Found it but still a bit far back (see photo) but looks like 712 wires will reach from shunt to pos on battery. Guess I look for fish line probe tool to do?

Garfish · 09-08-2019, 03:55 PM

Installing the 712 and roof solar as I need to get under front bed for both. Like anything that you want to do correctly (especially with electricity) it is 90% getting ready - tools, instructions, inspections, forums, buy the parts (Victron 712 and the MPPT) and examine the hardware and manuals, Home Depot and Amazon, youtube videos and back to these great forums.

Now I have many new tools I will probably use once, maybe twice (free loan of hydro crimp and wire stripper), extra parts I did not need, some new scrapes and cuts, question why pos buss bar uses rings and neg does not, that AS put the RJ 45 in bathroom already (thank you!), and wonder why pre solar has three ports all wired but they all must go to single green and yellow wire by the buss.

So, is this about camping or just being an AS addict? Lithium and inverter next or the new 23 globie twin beds? Endless

Garfish · 09-09-2019, 07:09 PM

Whoops - drilled hole in bathroom where RJ45 is only to find that the display connection is RJ12. Victron dealer says no adapter RJ45 to RJ12 but I have found them. Asking Victron if I might damage anything trying it. Otherwise I have to get the Victron cable back there (not sure but more holes) or cover the hole with something

pcskier · 09-09-2019, 07:28 PM

Quote:

Originally Posted by Garfish

Whoops - drilled hole in bathroom where RJ45 is only to find that the display connection is RJ12. Victron dealer says no adapter RJ45 to RJ12 but I have found them. Asking Victron if I might damage anything trying it. Otherwise I have to get the Victron cable back there (not sure but more holes) or cover the hole with something

If the adapters you've found don't work for some reason, you're still GOOD. You can use the existing factory RJ 45 wire, which is what I did, just using the six strands that match up with the six on the RJ12.

Cut the connectors off each end of the Victron-supplied RJ 12, leaving a few inches of cable. Same thing at each end of the existing RJ 45 in the Airstream. Just leave plenty of slack for you to work on it. Then strip the sheathing back, and strip and splice the six appropriate color-coded wires on the RJ 45 Airstream wire to the Victron wire using 22awg crimp connectors. I stripped enough bare wire to fold each over to double it up, so the crimp was good and tight. Just don't use the two unneeded strands of the Airstream RJ45wire. Bundle it all up with electrical tape. A bit tedious, having to do both ends with a total of 24 wire ends to strip and 12 crimp connections, but worked fine.

You could go out and buy RJ12 connectors and a special RJ crimping tool you'll never use again, and just assemble them using just the six needed wires, as long as you could figure out which wire goes in which slot. I found it easiest to just match the right colors from the RJ45 in the Airstream to the six wires on the RJ12, and call it good.