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Victron chargers cooperate?

NilsRain

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Nov 25, 2021
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I am doing a Ford Econoline van conversion.

I'm planning to have multiple Victron chargers: 30A MPPT, 30A dc-dc and 15A ac-dc into 200Ah of LiFePO batteries.

I was used to seeing batteries that can charge a 1.0C and was sure that I'd be under 0.5C (103A) so I wasn't worried.

I bought a SOK 206Ah battery and it has only 0.25C charging limit!

On the victron site the VE.Smart compatibility list says the multiple mppt and IP22 chargers will talk, but how can I throttle the dc-dc?

The 712 battery monitor is also VE.Smart compatible. Can it run the show?

What do I do now?
 
I am doing a Ford Econoline van conversion.

I'm planning to have multiple Victron chargers: 30A MPPT, 30A dc-dc and 15A ac-dc into 200Ah of LiFePO batteries.

I was used to seeing batteries that can charge a 1.0C and was sure that I'd be under 0.5C (103A) so I wasn't worried.

I bought a SOK 206Ah battery and it has only 0.25C charging limit!

On the victron site the VE.Smart compatibility list says the multiple mppt and IP22 chargers will talk, but how can I throttle the dc-dc?

The 712 battery monitor is also VE.Smart compatible. Can it run the show?

What do I do now?
Its unlikely that you will get anything like 30 amps out of your mppt controller, unless you have severely over paneled.
Even less likely while you are driving.

206ah * .25 = 51.5 amps
 
As was mentioned you are under the limit, so will not be an issue.

As an owner of 3 SCC Victron that can push more than the 60 amps of power my battery can take, I will tell you they are not networked to A total between the three for amps, but each needs to be set individually.
 
I thought there was a Victron gizmo that can read a battery shunt an command SCC to reduce output.
That would let full SCC output be driven if inverter is consuming some, but reduce as needed to stay within target battery charging.

So your SOK can accept 0.25C (within some temperature range), but you may be in cold locations. Whatever "C" rate you do charge at, set low-temperature disconnect according to temperature where that rate is acceptable.
 
The Victron 712 Battery monitor and shunt and the Victron SCCs can be put in a virtual network where they tap to each other. I’m not sure exactly what this does because the documentation about specifically what this network does is lacking.

I can put one SCC into equalization mode and the other two automatically enter equlization, so it does network that way. My battery is limited to 13% of the amp hour which is 60 amps, and my panels can make 74 amps in full sunshine. I have three SCCs. Two that are 30 amps, and one that is 50 amps. I wish there was a way to enter a 6 amp max for the sum of the production, but there’s not. I can enter 15 amps, 15 amps and 30 amps into the individual controllers, but this means I lose a lot of production throughout the day because the roof panels produce more at noon, but the portable panels produce more at sunrise and sunset.
 
I thought there was a Victron gizmo that can read a battery shunt an command SCC to reduce output.
That would let full SCC output be driven if inverter is consuming some, but reduce as needed to stay within target battery charging.

So your SOK can accept 0.25C (within some temperature range), but you may be in cold locations. Whatever "C" rate you do charge at, set low-temperature disconnect according to temperature where that rate is acceptable.

I think the device you're looking for is the Victron Cerbo GX. There are limits that can be set in it for all attached Victron devices. I don't have a Cerbo GX (yet!) so everything I know about it read on the Internet.

My Victron BMS-712 has my two Victron 100/50 MPPT networked together. But I've not found anything that would allow me to set a maximum charge current. My battery bank is 560 Ah of LiFePO4, so I'm well under the charge limit of the battery bank.

In theory, your planned devices could put you over the max amps that your battery can handle. I probably would change the DC-DC to a smaller unit, say 18 amps to keep under your limit.. A 30 amp DC-DC could pull 40 amps from your alternator and would require fairly large cables. I'm not including your 15 amp AC-DC converter because it's highly unlikely that it would be active when your DC-DC charger is active.
 
I am doing a Ford Econoline van conversion.

I'm planning to have multiple Victron chargers: 30A MPPT, 30A dc-dc and 15A ac-dc into 200Ah of LiFePO batteries.

I was used to seeing batteries that can charge a 1.0C and was sure that I'd be under 0.5C (103A) so I wasn't worried.

I bought a SOK 206Ah battery and it has only 0.25C charging limit!

On the victron site the VE.Smart compatibility list says the multiple mppt and IP22 chargers will talk, but how can I throttle the dc-dc?

The 712 battery monitor is also VE.Smart compatible. Can it run the show?

What do I do now?
Don't worry about the SOK limit of .25C. That is some weird recommendation that SOK puts out there for some reason. The SOK BMS will handle .5C charging and 1C discharge. Not sure how long it will hold up, but this has been tested to work. I have personally put 70A into my SOK 206 and pulled 150A.
 
Don't worry about the SOK limit of .25C. That is some weird recommendation that SOK puts out there for some reason. The SOK BMS will handle .5C charging and 1C discharge. Not sure how long it will hold up, but this has been tested to work. I have personally put 70A into my SOK 206 and pulled 150A.
Thanks, I was kind of assuming that the 0.25C was an extremely conservative artificial limit because it's so much lower than other makers.
 
I think the device you're looking for is the Victron Cerbo GX. There are limits that can be set in it for all attached Victron devices. I don't have a Cerbo GX (yet!) so everything I know about it read on the Internet.

My Victron BMS-712 has my two Victron 100/50 MPPT networked together. But I've not found anything that would allow me to set a maximum charge current. My battery bank is 560 Ah of LiFePO4, so I'm well under the charge limit of the battery bank.

In theory, your planned devices could put you over the max amps that your battery can handle. I probably would change the DC-DC to a smaller unit, say 18 amps to keep under your limit.. A 30 amp DC-DC could pull 40 amps from your alternator and would require fairly large cables. I'm not including your 15 amp AC-DC converter because it's highly unlikely that it would be active when your DC-DC charger is active.
A smaller dc-dc charger would make this work, but that's the only one I have bought already. Oh well.

Thanks for your replies, HRTKD and everyone else.
 
I think the OP is all good on his original concerns, but just to clarify a couple things with the victron chargers:

A cerbo device (or other GX device) can manage/sync charging activities and limit cumulative charge amps across supported devices.

Oddly enough, the orion charger is not a supported device. So, the cerbo can sync across multiple solar chargers and inverters, but it has no idea what the orion is doing and can't control it. As far as I know, you can't even limit output of the orion through the configuration/app. All you can do to control output is configuration of the charge profile and you can also turn the device on and off via the app.
 
It would be nice if Victron noted if the device is "Cerbo GX Certified", or something like that. Yeah, you can back into that same determination by checking to see if it has a VE.Bus or VE.Direct interface.
 
Do any of these devices (Cerbo in particular) ask the BMS how much current it would like?
Are they programmable to set charge current to zero at some temperature, or better yet to implement a curve?
 
It would be nice if Victron noted if the device is "Cerbo GX Certified", or something like that. Yeah, you can back into that same determination by checking to see if it has a VE.Bus or VE.Direct interface.
Agreed. It's somewhat obvious that the orion doesn't integrate with anything (except the app via bluetooth), but people tend to assume that high end components should have integration capability (particularly when most of their other components do). I went with Orion chargers because most of the rest of my system is victron, but there is really no advantage since they can't talk to anything. They work, but it just seems like Victron didn't get these right. I don't really care that much about all the synchronized charging and charging limits, but it's really annoying that I can't even see the amps these things are pushing through the cerbo monitoring system. The cerbo just takes the data from the shunt, properly categorizes all the supported charging sources (multi, SCC's), but then everything else goes into a general "DC" bucket. So, if my orions are charging at 60a and there is a 20a draw on the DC side at the same time, you just see a 40a inflow for DC. So, the "net" number doesn't provide an accurate view of what your actual DC loads are and you don't get any view of what the Orions are doing. You can go into the victron app and look at the output wattage of the orions and then back that out, but it's just dumb to have to do that manual math when it would be easy to just send that data from the orion to the cerbo (these chargers are not cheap, so expectations should be high). It's actually not that big of a deal since it's only a problem when the engine is running, but it's a glaring bit of missing functionality in an otherwise slick system.
 
Do any of these devices (Cerbo in particular) ask the BMS how much current it would like?
Are they programmable to set charge current to zero at some temperature, or better yet to implement a curve?
My Victron SCC can limit charging to 0 if it has a Victron temp device. I have two different systems and one temp sensor. I will put the Victron temp sensor on my cheap BMS that has an unadjustable low temp cut off too low so the SCC stops charging. For my bigger system with he trusty Overkill, I am trusting the BMS to shut off current.

I just learned about Cerbo being able to limit current from multiple devices, and may be interested in it because of this.
 
Do any of these devices (Cerbo in particular) ask the BMS how much current it would like?
Are they programmable to set charge current to zero at some temperature, or better yet to implement a curve?

The curve (decreased current as the temperature approaches 32° F) isn't something that I've seen. It's either charging or not charging. The temperature compensation is used for lead acid batteries and works the opposite way you want it to for LiFePO4 from what I recall.
 
I just learned about Cerbo being able to limit current from multiple devices, and may be interested in it because of this.
Not just limiting current across multiple devices, but other logic across devices. For example, it's able to shift charge source priority. For example, you might want to only charge via solar based on SOC or time of day, but then charge from grid also if SOC drops too low. I've read up a little on this and I'm not very knowledgeable, but there are lots of options for config.

Beyond the standard stuff, you can get into the "node red" world, which is basically open source modifications to the cerbo/venus operating system. From what I understand, it's pretty straight forward and you can pretty much build any logic, customize your own screens, control other connected devices (including non-victron devices that support the right protocols), etc. I haven't had the need/time to dig into node red, but it sounds like the sky's the limit if you have the desire and time to monkey with it. Check out the victron community forums for more info on it.
 
The curve (decreased current as the temperature approaches 32° F) isn't something that I've seen. It's either charging or not charging. The temperature compensation is used for lead acid batteries and works the opposite way you want it to for LiFePO4 from what I recall.

I'll bet Tesla does it in their cars. Although it is possible they only use active temperature control. But if the degradation vs. current at temperature is real and significant, regulating current to mitigate is trivial (given control over charger.)

I thought about lead-acid profile being tricked with analog control of temperature sensor port. Problem is, the compensation is a modest adjustment of CV limit. An absurd temperature would have to be emulated to alter current at low voltage low SoC, and inverter would interpret that as way over-temperature.

Just a few analog and/or digital hooks to command CV and CC is all we ask ...
 
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