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Using Victron Lynx to connect battery bank?

Firstascent

Solar Enthusiast
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Mar 7, 2020
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So I was looking into the Victron Lynx Distribution setup as I really like the design of it for my DC loads and I came across this photo (attached) in the manual for it and it got me thinking about using it to parallel my cells together.

since this is able to be fused for each of the four connections, what would be any cons to using this to attach each of my 4s batteries to it to make them 4s4p?

off the top of my head, there would be more large wires having to connect each 4s to the distribution unit as opposed to just connecting the entire 4s4p bank to it with a single pair of 4/0 wires.
The positive side is that it would be very easy to take a 4s bank out of service if a cell goes bad etc.

My battery bank is 16 LFP 280ah cells which will be a 12v config in 4s4p and will be installed on my RV.

Any other cons you guys can think of doing it this way?
 

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This looks just like the lynx distributor and is made for you purpose.
It contains no fuses as you want the fuses as close to the batteries as possible.
 
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This looks just like the lynx distributor as is made for you purpose.
It contains no fuses as you want the fuses as close to the batteries as possible.
Yes I’m aware of that unit as well (and it’s cheaper) and good point about having the fuse as close to the battery as possible instead of having it neatly within the distributor unit :)

even with using the Power-In unit, I’d still consider using it to parallel my bank. Still unsure if I want to deal with the extra wires since they’ll be larger, and anything else I may not be thinking of.
 
Using the Power_in to to parallel your batteries makes maintenance easier.
I'm not a Victron fanboy but imho these are great distribution kit.
 
This is exactly what I do. I use a Lynx Distributor for input from my 4S, 12V batteries. I have a separate Blue Sea Systems battery switch for each battery so I can take one in/out of service as necessary. Frankly, switching each battery separately is overkill, but I don't see enough voltage drop for it to cause any issues because my cables are short. Here is a video on how to add fuses to a Lynx Power In. I use 2/0 cables from each battery to the input Lynx. I have another Lynx after the shunt to connect my Multi and MPPTs. I run two sets of 2/0 from the output Lynx to the Multi because 2/0 is easier to deal with in tight spaces than 4/0.
 
Using the Power_in to to parallel your batteries makes maintenance easier.
I'm not a Victron fanboy but imho these are great distribution kit.
yeah that's what I was thinking too. it's always good to hear good comments about a product from people who are not deep into the Victron ecosystem and less biased haha.
This is exactly what I do. I use a Lynx Distributor for input from my 4S, 12V batteries. I have a separate Blue Sea Systems battery switch for each battery so I can take one in/out of service as necessary. Frankly, switching each battery separately is overkill, but I don't see enough voltage drop for it to cause any issues because my cables are short. Here is a video on how to add fuses to a Lynx Power In. I use 2/0 cables from each battery to the input Lynx. I have another Lynx after the shunt to connect my Multi and MPPTs. I run two sets of 2/0 from the output Lynx to the Multi because 2/0 is easier to deal with in tight spaces than 4/0.
Since you're using the distributor are you fusing the batteries in the lynx still?
I wouldn't be using the Victron shunt with it since I'm using a Batrium BMS and, I believe, it has to use the Batrium shunt (which I have).

Interesting you opted for two sets of 2/0 from lynx to multi rather than one 4/0. Agreed 2/0 is easier than 4/0, I guess it makes sense. I know all about tight spaces since this will all be going in my RV.
I'd love to see any photos if you have them handy.
 
Sure thing. Not shown is the Cerbo GX I added later or the temperature controlled exhaust fans and intake vents. This all fits under the bed in the front of the RV. I have 1,600 watts of PV on the roof and another 300 watts in solar awnings (or ground mount). My travel trailer only has a 30 amp, single phase input so that made the job a bit easier, but also limited me to a 120 volt mini-split air conditioner I installed this Summer. The Lynx on the left and the four switches above it are for four battery banks (only two are currently installed). Each battery has its own fuse in Lynx. It feeds through a Victron BMV-712 shunt. The Lynx on the right has two 2/0 connections to the Multi, one connection to the large MPPT, and one connection to feed 12v to the accessories, lights, pump, etc. via a Victron 65 amp smart battery connect. The small fuse panel on the left also connect to the main bus bars on the right side Lynx for DC loads not coming from the main DC panel in the RV such as the front tongue jack, trailer brake away system, and small MPPT for the solar awnings.

When my battery cells get here in the next 4-6 weeks I'll add two more battery packs. I may add another Lynx for the load side since I need to add another MPPT for two or three more panels I'm going to add to the roof when I remove the roof-top air conditioner.

I used Overkill Solar BMS's on the batteries and they do not communicate with my system. There is an open-source serial driver for VenusOS, which runs on the Cerbo, to connect the BMS's, but it currently doesn't support more than one BMS. Eventually, hopefully, I'll get those communicating with the Cerbo.

IMG_5354.jpegIMG_5362.jpegIMG_5366.jpegIMG_5375.jpeg
 
Are those current transformers or just big chokes on the inverter/charger leads?
 
Are those current transformers or just big chokes on the inverter/charger leads?

Just big chokes. Mix 31 ferrites for RFI suppression. I went with a stack of three of ferrites on the inverter side and three more on the battery side. Winding through torroids would provide much more choking impedance but it's hard to wind 2/0 through a torroid.
 
Sure thing. Not shown is the Cerbo GX I added later or the temperature controlled exhaust fans and intake vents. This all fits under the bed in the front of the RV. I have 1,600 watts of PV on the roof and another 300 watts in solar awnings (or ground mount). My travel trailer only has a 30 amp, single phase input so that made the job a bit easier, but also limited me to a 120 volt mini-split air conditioner I installed this Summer. The Lynx on the left and the four switches above it are for four battery banks (only two are currently installed). Each battery has its own fuse in Lynx. It feeds through a Victron BMV-712 shunt. The Lynx on the right has two 2/0 connections to the Multi, one connection to the large MPPT, and one connection to feed 12v to the accessories, lights, pump, etc. via a Victron 65 amp smart battery connect. The small fuse panel on the left also connect to the main bus bars on the right side Lynx for DC loads not coming from the main DC panel in the RV such as the front tongue jack, trailer brake away system, and small MPPT for the solar awnings.

When my battery cells get here in the next 4-6 weeks I'll add two more battery packs. I may add another Lynx for the load side since I need to add another MPPT for two or three more panels I'm going to add to the roof when I remove the roof-top air conditioner.

I used Overkill Solar BMS's on the batteries and they do not communicate with my system. There is an open-source serial driver for VenusOS, which runs on the Cerbo, to connect the BMS's, but it currently doesn't support more than one BMS. Eventually, hopefully, I'll get those communicating with the Cerbo.

View attachment 58980View attachment 58981View attachment 58982View attachment 58983
Thanks for the info and photos! Greatly appreciated. I like how you used the space under the bed, right now I have the big open space and I don't use it. However, I'm currently considering that for my build I'm going to install mine in my front compartment where my generator is (and current original batteries are) on my fifth wheel.
 
Just big chokes. Mix 31 ferrites for RFI suppression. I went with a stack of three of ferrites on the inverter side and three more on the battery side.

How is the RFI from say 6m - 160m ?

Did you scan pre and post choking ?

Thanks.
 
Just big chokes. Mix 31 ferrites for RFI suppression. I went with a stack of three of ferrites on the inverter side and three more on the battery side. Winding through torroids would provide much more choking impedance but it's hard to wind 2/0 through a torroid.
It was my understanding the cable had to wrap one turn around the ferrite cores but I see them just passing thru the center on the battery cable.

Did that provide any suppression and where did you see the most RFI emminating from?
 
Each pass through the center of the core is one turn. I didn't measure RFI before and after. I didn't have my spectrum analyzer at the time. That said, the 1" split-core ferrites on the battery cables all buzz in volume proportional to the load - whether from the MPPTs or AC charger. So something is happening, but it may not be common mode RF currents on the cables.

That said, all my mitigation calms the RFI to decent levels except for the large Victron MPPT controller (150|100). If you put that under load, it wipes out 80m-10m. I have an engineering note into Victron about the issue but I've been advised that might take several months. ?‍♂️
 
The Power-In can be easily modified to accept fuses and become the exact same as the Lynx - except for the LED's wont work. Parts list here -
I wonder if all the diodes in solar setups add to the RFI going on ??
 
I used Overkill Solar BMS's on the batteries and they do not communicate with my system. There is an open-source serial driver for VenusOS, which runs on the Cerbo, to connect the BMS's, but it currently doesn't support more than one BMS. Eventually, hopefully, I'll get those communicating with the Cerbo.

Impressive setup. My only criticism is those disconnects need labels! :D

The driver you referenced will not get you where you want to go.


The driver will communicate with a Battery Management System (BMS) that support serial communication (RS232 or RS485) Modbus RTU type commands and publish this data to the dbus used by VenusOS. The main purpose is to supply up to date State Of Charge (SOC) values to the inverter, but many extra parameters are also published if available from the BMS.

The BMS must be capable of data output. The Overkill isn't. If you're a genius and you can design a device that reads the BMS data from the overkill via bluetooth and can translate that information into the format the Venus needs, you'll get there. Lotsa effort. Probably more cost effective to get one that already supports the communication via CAN.

REC, Batrium and Orion are the names that come to mind.
 
Sure thing. Not shown is the Cerbo GX I added later or the temperature controlled exhaust fans and intake vents. This all fits under the bed in the front of the RV. I have 1,600 watts of PV on the roof and another 300 watts in solar awnings (or ground mount). My travel trailer only has a 30 amp, single phase input so that made the job a bit easier, but also limited me to a 120 volt mini-split air conditioner I installed this Summer. The Lynx on the left and the four switches above it are for four battery banks (only two are currently installed). Each battery has its own fuse in Lynx. It feeds through a Victron BMV-712 shunt. The Lynx on the right has two 2/0 connections to the Multi, one connection to the large MPPT, and one connection to feed 12v to the accessories, lights, pump, etc. via a Victron 65 amp smart battery connect. The small fuse panel on the left also connect to the main bus bars on the right side Lynx for DC loads not coming from the main DC panel in the RV such as the front tongue jack, trailer brake away system, and small MPPT for the solar awnings.

When my battery cells get here in the next 4-6 weeks I'll add two more battery packs. I may add another Lynx for the load side since I need to add another MPPT for two or three more panels I'm going to add to the roof when I remove the roof-top air conditioner.

I used Overkill Solar BMS's on the batteries and they do not communicate with my system. There is an open-source serial driver for VenusOS, which runs on the Cerbo, to connect the BMS's, but it currently doesn't support more than one BMS. Eventually, hopefully, I'll get those communicating with the Cerbo.

View attachment 58980View attachment 58981View attachment 58982View attachment 58983
Nice, I also want to put a shunt between the lynxs. Where did you find those parts? That bus bar looks exactly like the lynx bus bars. I see you have some magic going on with a flex cable there as well. Care to help me accomplish the samish thing?
 
Nice, I also want to put a shunt between the lynxs. Where did you find those parts? That bus bar looks exactly like the lynx bus bars. I see you have some magic going on with a flex cable there as well. Care to help me accomplish the samish thing?
Btw, if you want to pay for it, the Lynx Shunt is a slick setup of your already going to be using other lynx components. But yeah it is expensive, at the end of the day it’s still just a Shunt :)

If you’re wanting to use your own or a different less expensive Shunt I would simply buy some copper busbar from Online Metals, they have many sizes and tinned options too, it would be cheap since you only need to order a foot and then cut to length and drill some holes.

But I don’t have the details on exactly what @K8MEJ did but I bet it’s something similar
 
Btw, if you want to pay for it, the Lynx Shunt is a slick setup of your already going to be using other lynx components. But yeah it is expensive, at the end of the day it’s still just a Shunt :)

If you’re wanting to use your own or a different less expensive Shunt I would simply buy some copper busbar from Online Metals, they have many sizes and tinned options too, it would be cheap since you only need to order a foot and then cut to length and drill some holes.

But I don’t have the details on exactly what @K8MEJ did but I bet it’s something similar
I have a BMV700. Would I then need an additional monitor?
 
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