Victron shunt mounting in RL

msmolow

2019 Unity CB / 2018 Chas
Try disconnecting your smart shunt from your battery positive to remove all power. That will force a reset and it will take a full charge cycle before it gives a 100% soc value if you have turned off "battery starts synchronized".
If that doesn't work search your question here:
 
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msmolow

2019 Unity CB / 2018 Chas
Don't know if it will help but I use a SmartShunt with LTV FLA batteries.
Here are my settings. The 98.5% SOC is what I am currently at in the storage lot.
Note the balmy 29 degrees at 10:28 pm here in Northeastern PA. I'm tired of winter already!

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SSTraveler

2014 LTV Unity Murphy Bed
I experimented with the Victron BMV-712 and SmartSolar 100/30 settings and at a charge voltage of 13.2v my FLA nor AGM batteries never fully charged. I decided to entering my own "User Defined" setting parameters and now my Interstate AGM (210ah) batteries are more fully charging. AGMs are very sensitive to over charging so I want my system to keep my batteries topped up to just over 13.0v. Resting voltage for AGMs is around 13.10v. I watch my Solar controller history minimum voltage reading (I loosely define it as Resting voltage) when in storage to monitor the consistency of the those reading to verify my batteries are being charged to just over 13v, and not over charging. Here are the settings I use for my Interstate AGM batteries and the battery voltage chart I use to cross check the BMV-712 readings to make sure my batteriesare performingas expected. I try to manually synchronize my SOC as often as I remember, Victron recommends this.
 

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Peter Tourin

2020 Unity RL, ex 2012 Unity MB
Iʻm waiting for some info from Brian at LTV - I donʻt know what they consider the capacity of their current Discover batteries and I donʻt know how they configure the Sterling and Xantrex chargers. I used AM Solarʻs suggestions for Victron settings for AGM batteries: Charged voltage 14.1, Tail current 2%, Peukert Exp 1.12, Charge Efficiency Factor 97%.

Keep in mind that Victron defines 100% SOC as the point where Charge voltage goes above the setpoint, Tail Current goes below the setpoint, and it stays that way for 3 minutes. What I believe is happening is that on shore power, the Xantrex drops from Absorption to Float mode before the current gets down to 2% (thatʻs around 4 amps) - the float voltage is below 14.1 so the Victron never gets to its 100% SOC definition. Iʻll know more about this after I get the info from Brian and watch the system on a few trips.

I did have "Battery starts synchronized" checked, but as soon as I hooked everything up I manually dropped the % SOC down to about 90% to make sure I didnʻt hit 100% too soon - I wanted to see the 3 Victron values (14.1v, 4 amps, hold for 3 minutes) met and then manually synchronize. That worked fine while driving - I watched the voltage climb over 14.1, then the tail current dropped below 4 amps. But when the Xantrex was doing the charging, I had the voltage over 14.1 and the tail current was down below 7-8 amps - I walked away for a short while and when I came back the current was below 4 amps but the voltage was down too low - thatʻs why Iʻm guessing what I said about the Xantrex charge curve.

This stuff always seems to be funky and confusing at first, till you get used to the components in the new system. Weʻll see...
 

Peter Tourin

2020 Unity RL, ex 2012 Unity MB
I got a bit of info from LTV yesterday that Iʻll pass on. Here are their Xantrex and Sterling settings. This was a bit of a surprise, if Iʻm reading them right. They use the "Sealed" setting for the BB1230 - 14.4 Bulk/Absorption and 13.6 Float. For the Xantrex they use 14.2 and 13.2.

I looked up the Discover Dry Cell EVGC-6A-A specs on the manufacturerʻs site. It appears that they suggest 14.7 Bulk/Absorption and 13.6 Float. I hope Iʻve got all this right - this was my first look <g>...

What I still donʻt know is how the Sterling and the Xantrex charge curves are "tailored" - specifically, when they switch to Float. My present Victron settings expect to auto-sync when voltage climbs over 14.1, current drops to below 4 amps, and it stays that way for 3 minutes. Usually the voltage setpoint is the first to be met. But if one of the charger curves switches to Float before the current drops to 4 amps, the Victron wonʻt auto-sync.

This used to be important to me in my MB - I installed early Lithiums with no BMS to speak of, and built a charging system that was controlled by a Victron BMV-702 (the control relay turned charging on and off). Not so important now since the charging is all being done by the LTV setup - Iʻm only monitoring it, and having a good 100% SOC is only a convenience to me. But I still like to know what LTV has installed, how they configured it and how it actually works. Having a good time figuring it out <g>...
 

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SSTraveler

2014 LTV Unity Murphy Bed
The first page of this thread offers some great buss bar ideas for installing a Victron Shunt but for those looking for an easier, quick off the shelf approach you can always just buy a 12" battery cable and use it to very simply add the Victron Shunt. Many people are choosing the new Victron Smart Shunt because it's less expensive and simpler since you aren't installing the remote display. For this installation I recommend a 2/0 battery cable with 3/8" lugs, that should accommodate most every battery post/Terminal size and the cable diameter is equal to or greater than any battery connection cables used by Leisure across all year and models. You always want to ensure any cable you are using for the Victron Shunt is at least equal or greater in diameter size to be safe!

As you can see from the attached table the wire diameter gets smaller as the number gets larger. So 9 is the smallest and a 1 is largest. But above 1 or in the Zeros, it's the opposite, the wire diameter gets larger as the Zeros grow so a 1/0 or 0 is smaller than a 2/0 or 00 wire and so on. On the newest Leisure models with a 2000w inverter, the batteries are connected with 2/0 cable so you would need to select a Victron Shunt connection cable that is equal to or greater to be safe. Therefore you need at a minimum a single 2/0 cable. You can order a pair from Amazon or try going to your local auto parts store and see if you can just buy one there. In my 2014, Leisure used 4awg cables to connect my original Flooded Wet Cell Batteries to the coach. So I would buy a 4 awg or 2 awg battery cable. The length of the new cable should always be as short as possible and a 12" cable with 3/8" lugs is readily available for purchase. I think with my diagram you'll see you can add a Victron shunt in just minutes with an adjustable wrench. Make sure you program the shunt for your battery type. I want to emphasize if you have more than one negative cable/wire attached to your battery (other than a Leisure installed temperature sensor) then all these need to be connected to the opposite end of the Victron Shunt in order for the Shunt to work properly and display all incoming and outgoing battery amperage.
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SSTraveler

2014 LTV Unity Murphy Bed
Very nice, another simple off the shelf alternative. A BlueSea 9159 bar is rated at 250a, so one is perfect for ~200ah of batteries. It is also made from tin plated copper for maximum conductivity and corrosion resistance. The main concern in using a bus bar or cable lugs made of pure copper is the surface oxidation of pure copper, it does affect circuit resistance and battery performance and for this reason it has been discovered that nickel or tin plating is very important. Copper sulfides are accelerated with DC transfer physics.

If you make your own "flying bus bars," be sure to have good terminal boots and protection against possible short circuit. I have not been able to find any tin or nickel plated copper bar stock, so if I need to use pure copper I will also use Noalox Anti-Oxidant Compound, https://www.amazon.com/Anti-Oxidant...child=1&keywords=Noalox&qid=1611140476&sr=8-1. It's also a good practice to cover the ends of your copper wire cables before crimping a lug on them.
 
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treemaze

2020 Unity MB
McMaster-Carr sells silver plated copper bars -- slows the oxide buildup. The 0.25" x 1" bar has about the same cross-section as a 4/0 cable.

 

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