Victon System questions

[DP425]

I've got a few questions I could use a hand on.
My System as it stands, is a Victron Quattro-II 2x120 and three SOK 206AH batteries. Not yet installed, but these components on hand.

Questions are as follows:
1- I want to use the Lynx connection system; I obviously do not need, nor can I use the Lynx BMS. However, I'm a bit unclear on if the Shunt has a value when not using the BMS or a GX monitoring device (I do not currently plan on running one). It sounds like one of the two are required to be able to pull data from it.

2- Does the Quatro-II have built in bluetooth for the app, or is a separate device required?

3- The three SOK batteries are to reside in factory battery trays in my toy hauler. These three will fill my tray space. This area is weather protected, but not conditioned; I could probably convert it over to conditioned, but I bought the batteries with the heaters to avoid this. I decided to use the factory tray space, as I really don't want to use up the space in my "basement", and I'm just not comfortable sleeping directly over batteries (so I won't mount them under my bed). Anyway, if I decide three batteries isn't enough, am I asking for trouble mounting another battery or two, or three, inside a conditioned space (the "basement"), while the other three are not in a conditioned space (temp differential).

4- The Quattro-II has 70a of charging. The SOK batteries each have a recommended charge current of 40a, and a max of 70. So at the recommended current, I'm coming up 50a short, but could reasonably use another 100a. Can I add an auxiliary charger, such as the Smart IP43 Charger, 50a model? I'm assuming so, but I thought it better to ask.

I'll have to come back later to start the discussion on Solar (where I feel woefully under informed). That's a next year project.

 

[Rocketman]

I would highly recommend one shunt - if you use the bmv712 you can bolt it directly on the Lynx. I just helped by brother in law install a system in his 5th wheel - we used one Lynx (with fuses added- see YouTube) for the batteries to connect. Then we had the shunt (negative) and a on/off switch (positive) they were bolted directly on the “distributor” Lynx - we used a few short pieces of 1/4” x 1” tin plated copper bar (from on-line metals.com) as bus bars to connect to the power Lynx.

The Cerbo-S and touch is really nice and gives great information about your system.

600ah is a lot of power - (I have 544ah) it is plenty unless it is cloudy for 2 days or need the air conditioner (then the generator needed ran anyway). I have 1500w of solar.

You can add another charger - but see how it goes first…

 

[DP425]

I would highly recommend one shunt - if you use the bmv712 you can bolt it directly on the Lynx. I just helped by brother in law install a system in his 5th wheel - we used one Lynx (with fuses added- see YouTube) for the batteries to connect. Then we had the shunt (negative) and a on/off switch (positive) they were bolted directly on the “distributor” Lynx - we used a few short pieces of 1/4” x 1” tin plated copper bar (from on-line metals.com) as bus bars to connect to the power Lynx.

Yeah, I've seen that. I was REALLY hoping the lynx shunt would be of use without having the BMS or GX device. I really don't understand why they don't have the ability to read it built into the Quattro-II. I would think it could provide some pretty useful information to the unit. Anyway, I just like how clean it looks with lynx.!

 

[Rocketman]

I agree the Lynx is nice and clean!

You will need a way to control the Quattro.

The control I am talking about is adjusting the 120v amp input (on 50a - 30a -35a (my generator)-15a or 10a (lowest for my Multiplus). Also switch between on/off/inverter only/charger only.

There are three different ways.
1. MCU panel. Expensive for what it does - save the money and invest it in #3.
2. VE.Bus smart dongle- cheapest. Can make the adjustments on your Bluetooth phone.
3. GX device I.e. Cerbo. This is the best Cerbo-S is a little cheaper. You will probably want a Touch50 (display). It is expensive, but it does a lot of other stuff too.

It summarizes your system into a single point, so you and anyone else in the rig can easily understand what is happening. Also, the DVCC is really good feature.

VRM is really nice - this puts the cerbo’s data on the internet so you can check up on it. A bit ago my rig was in the shop for a bit (we full-time), it was really nice that I could look up and make sure the rig had power. (So our residential fridge stayed running) - nice peace of mind.

Good Luck

 

[Brucey]

4- The Quattro-II has 70a of charging. The SOK batteries each have a recommended charge current of 40a, and a max of 70. So at the recommended current, I'm coming up 50a short, but could reasonably use another 100a. Can I add an auxiliary charger, such as the Smart IP43 Charger, 50a model? I'm assuming so, but I thought it better to ask.

That recommended charge current is the max recommendation. You can go below that threshold no problem at all.

 

[corn18]

What do you want your battery system to do? Figure this out first and then we can help make sure you don't waste money.

 

[DP425]

What do you want your battery system to do? Figure this out first and then we can help make sure you don't waste money.

Run one AC unit overnight, plus RV refrigerator, CPAP, phone chargers.

Where I’m at in MI, the AC won’t have to be on a cooling cycle the whole night, for the most part. Even if it did, I’ll have the generator set for auto start.

Then during the day, both AC’s may need to run, so I’d be running the generator anyway. 5500w, I’d be left with at least 2500 for charging and incidental needs. Seems I would be able to run nearly 170a of charging and not exceed the generator’s capacity. Plus with the Quattro’s ability to reduce charging to accommodate load limitations on L1, I would still have room for incidental demand. Not that I need so much charging capacity with 3-4 batteries.

So here’s another question someone might know. In the Cerbo GX, can the Quattro be setup to turn off the generator when the batteries are charged? What about predictive/scheduled charging? Say, I want my batteries full charged at 9pm. Can it be setup to know how charged the batteries are, and predict when it needs to start the generator to have a full charge by 9pm?

 

[Brucey]

Run one AC unit overnight, plus RV refrigerator, CPAP, phone chargers.

Where I’m at in MI, the AC won’t have to be on a cooling cycle the whole night, for the most part. Even if it did, I’ll have the generator set for auto start.

Then during the day, both AC’s may need to run, so I’d be running the generator anyway. 5500w, I’d be left with at least 2500 for charging and incidental needs. Seems I would be able to run nearly 170a of charging and not exceed the generator’s capacity. Plus with the Quattro’s ability to reduce charging to accommodate load limitations on L1, I would still have room for incidental demand. Not that I need so much charging capacity with 3-4 batteries.

So here’s another question someone might know. In the Cerbo GX, can the Quattro be setup to turn off the generator when the batteries are charged? What about predictive/scheduled charging? Say, I want my batteries full charged at 9pm. Can it be setup to know how charged the batteries are, and predict when it needs to start the generator to have a full charge by 9pm?

I haven't used it but you can enable node red on a Cerbo/Venus os device, gives you the control you are looking for I believe

Venus OS Large image: Signal K and Node-RED [Victron Energy]

www.victronenergy.com

 

[Rocketman]

The Quattro doesn’t turn on/off the generator- that’s the Cerbo’s job. The Cerbo will know the battery SOC (state of charge) from the shunt (Smartshunt, bmv712, or Lynx shunt),

With the standard programming of the generator start/stop it has low state of charge times (start at 25% SOC) and time based - run for 60 min.(whatever you set it for). There are more options available and LOTS with node red but I haven’t used either so I can’t comment much.

 

[DP425]

Lets talk DC power switches.

Blue Sea Systems, seems to have one that goes up to 600a continuous. 900a intermittent (up to 5min periods). I'm thinking I'll place this between the batteries (on two Lynx Class T Power In) and the lynx shunt. The Quattro appears as though it can pull a max of about 450a during surge, so far from 5min, and still with 150a to spare. Additional loads are going to largely be negligible; 12v to run the propane refrigerator, interior lights, water pumps. Those loads that are note worthy, will be rather intermittent, such as my hydraulic leveling jacks and slide out motors. The shunt is fused at 900a. I bought the fuse before looking at DC battery switches and finding out there really doesn't appear to be options over 600a continuous. So concern here is, the chance this switch could be my failure point instead of the 900a fuse.

I do have each battery on a 250a class t fuse. At three batteries, there's now an upper limit of 750a. Still well above that 900 on the Shunt.

So what does everyone think? Do I need to try to find some sort of obscure alternative between the power in and the shunt?

Any opinions on putting each battery on a switch before the power-in (and thus, fuse)? My gut says the first thing after the battery needs to be a fuse. But I figured it wouldn't hurt to inquire. Really only serve the purpose of being able to take a battery out of the system quickly, without having to open the power-in cover and remove a fuse. Seems like that would be a pretty infrequent need.

 

[Brucey]

Lets talk DC power switches.

Blue Sea Systems, seems to have one that goes up to 600a continuous. 900a intermittent (up to 5min periods). I'm thinking I'll place this between the batteries (on two Lynx Class T Power In) and the lynx shunt. The Quattro appears as though it can pull a max of about 450a during surge, so far from 5min, and still with 150a to spare. Additional loads are going to largely be negligible; 12v to run the propane refrigerator, interior lights, water pumps. Those loads that are note worthy, will be rather intermittent, such as my hydraulic leveling jacks and slide out motors. The shunt is fused at 900a. I bought the fuse before looking at DC battery switches and finding out there really doesn't appear to be options over 600a continuous. So concern here is, the chance this switch could be my failure point instead of the 900a fuse.

I do have each battery on a 250a class t fuse. At three batteries, there's now an upper limit of 750a. Still well above that 900 on the Shunt.

So what does everyone think? Do I need to try to find some sort of obscure alternative between the power in and the shunt?

Any opinions on putting each battery on a switch before the power-in (and thus, fuse)? My gut says the first thing after the battery needs to be a fuse. But I figured it wouldn't hurt to inquire. Really only serve the purpose of being able to take a battery out of the system quickly, without having to open the power-in cover and remove a fuse. Seems like that would be a pretty infrequent need.

That blue seas switch is prob not rated for 48V nominal operation. The only one that seems to be 60V rated is the Victron 275A one. There is a tandem MNEDC250 breaker option around, can't find it now that should provide 500A of OCP and they are fully rated to disconnect under load.

 

[Brucey]

If you are running 12 or 24V then no worries there.

 

[corn18]

I was using a Blue Sea Systems 600A switch for my 12V system. Max draw through the switch was 325A. The actual switch itself would get to 120 deg F @ 82 deg F ambient. That bugged me so I replaced it with a Cole Hersee 500A switch. That switch also gets about the same temp @ 325A. I guess I am just stuck with a switch that gets warm @ 325A.

 

[HRTKD]

I have that Blue Sea Systems switch in my 12 volt system. I haven't drawn more than ~200 amps from the LiFePO4 battery bank. My rooftop RV air conditioner uses a soft start device, so my surge amps aren't that bad, but the system (Multiplus 12/3000) ran the air conditioner even without the soft start.

I'm using a single 225 amp Class T fuse between the battery bank and the switch. Yes, it should be two fuses to isolate the batteries. Do as I say, not as I do. I would point out that I have yet to blow a fuse in my system. The two LiFePO4 batteries each are 280Ah with a 120 amp BMS.

I stress tested my system by charging my EV from the trailer, pulling a bit more than 200 amps for about three hours. No hot spots, the system ran fine, but I did add vent fans after that for the battery and inverter compartments.

 

[justinm001]

The Quattro does have relays you can program and if your generator has a way to receive you could have it auto stop that way. (close relay when SOC is 80%)

The only reason to get a lynx shunt is if you want bms-can (ethernet) vs vedirect (loose plug). You can drill out the lynx distributor hole a bit and put a smartshunt its a bit thicker so a thin piece of wood helps). The lynx shunt looks better and has a fuse built in, but doesn't have bluetooth at all so will do nothing for you.

Get a CerboGX. You can get the -s and its like $200. This opens up the entire free suite so you can log and see everything. Worth thousands just to help troubleshoot as you can see the voltage of the quattro vs the shunt and such. Plus it is specifically designed to turn on/off generators that have autostarts. Can even program it to run an 30mins a month but only if it hasn't ran... perfect for generator testing and making sure all is good.

By default the cerbo doesn't do predictive charging but you basically set it like on at 50% then off at 80%. There's no real point for predictive charging or such because it'll autostart and turn off. I'm not sure if you can tell it to start then it'll auto turnoff at say 80%. There might be dedicated off hours for genset, i can't remember. They do have some predective charging for solar/shore which is new and really cool.

Problem with predictive charging and RVs is our power consumption is very random. Most power is AC and AC is dependent on outside temps so a 70deg day is much less than a 90deg day. Same if you're parked in sun/shade or even which direction.

The recommended charging rate is for max charging. You can safely charge as low as you want, even trickle charge 1a if you want. 70a likely sets off the BMS and anything close to that can set it off or cause overheating issues. 600ah of batteries and 70a charger means 10hrs to charge from 0 which seems pretty ideal as overnight it'll be charged.

 

[HRTKD]

Can even program it to run an 30mins a month but only if it hasn't ran... perfect for generator testing and making sure all is good.

I never thought of doing that. That would be interesting to implement. I manually run the generator once a month to exercise it, so that would save me a trip to the storage lot.

 

[justinm001]

I never thought of doing that. That would be interesting to implement. I manually run the generator once a month to exercise it, so that would save me a trip to the storage lot.

It's a default autostart option. I really like that if runs only if it hasn't been started so if you do use it then the 30 day countdown resets. I still haven't ran the wire to autostart yet so not sure how it works. Need to though as I found out yesterday I left a cheap battery charger plugged into the battery but unplugged from 120v and it must have drained the genny batt.

Ordered victron chargers that come tomorrow. No more cheap chargers.