Unanswered Questions in busbar

I purchased 3 x 200Ah (12V) Smart Lithium batteries to replace the AGMs on my boat. Also purchased the VE Bus BMS v2, Lynx Distributor, and already have Cerbo, Multiplus, etc. The batteries are to be connected in parallel.

Section 4.6.4 of the Smart Lithium manual has a schematic showing connection of parallel batteries individually to busbars with a fuse on the positive cable (for cable protection). Question: could this be a MRBF fuse on the battery post? Would a MRBF fuse be better than using a Mega fuse (has much higher Interrupt Capacity)?

Further, this section also states that "connect the cables diagonally to ensure equal current path through each battery". This arrangement would be far easier (than the busbar method) in my constrained location. Is this equally acceptable for paralleling 3 batteries? And can/should I place a MRBF fuse at each positive terminal post (I have never seen a schematic or video of this!), or simply connect the cables post-to-post, and then have a T-fuse (or ANL fuse), very close to the batteries, on the cable to the Lynx Distributor (for DC Loads & Chargers)?

Thank you for feedback and suggestions.

Hi,

I'm finalising my schematic for moving from AGM to Smart Lithium 3 x 200Ah (12V). System also has Multiplus 2000, Cerbo, SmartShunt, MPPTs, additional Phoenix charger, etc. I'm looking how to best create the Positive Main Busbar. Here is the current plan and questions:

- 3x200Ah Smart Lithium connected via individual ANL fuse holders (CIP106100000) to the Victron 500A busbar (CIP100400060). Three connections.

Question: can I fit the 500A Busbar over the bolts of the ANL fuse holders (as Victron shows for the "Modular fuse holder MEGA fuse (CIP100200100))? To avoid a squeezed fit, could use holes 1, 3 & 5 of busbar.

From this Busbar, I would also connect (possibly on the opposite side):

- Multiplus via a 250A or 300A MEGA fuse (max continuous current for Multiplus 2000 is 160A) using the "Fuse Holder for MEGA fuse (CIP100100001)" .

Question: is this OK, or must/should I use instead the (blue interlocking) "Modular fuse holder Mega fuse (CIP100200100)"?

- DC Loads via a Smart Battery Protect 220 - same question as for Multiplus on the use of the fuse holder.

Second Busbar (mainly for Chargers) would be also the Victron 500A busbar (CIP100400060).

Question: can I use the "Fuse Holder for Mega fuses (CIP100100001)" with this busbar?

Last question:

Can I inter-connect both Victron 500A busbars (CIP100400060) using the M10 bolt (i.e. both busbars 'join' at M10 hole and then use the provided M10 stainless bolt or a slightly longer one).

I have considered in some detail using the Lynx PowerIn or Distributor, but I do not want/need any of the negative busbar connections as my boat already has an extensive Negative Main Busbar and I don't want to be cutting and re-crimping over 20 cables!. And the Lynx only has 4 (max 5) studs for Mega fuse connections, and I need more.

Thank you,

JM

Hey there,

I've already done a couple of installations which all runs fine. I always stick to the "Unlimited wiring" guide for best DC / AC cabling. Normally there is plenty of space to have one big battery bank with equal DC lengths (f.e. multiple Pylontech + Victron Lynx).

Now I will install a bigger bank on a boat (catamaran) and would like to know which way would be best. Both options have pros & cons, maybe there is a third option I don't have in mind.

There is a bit space in each hull and in the middle of the catamaran. Which makes me have 4 spaces for the batteries.

Each battery pack will have it's own BMS. In total the battery will consist of 144x 280Ah Lifepo cells.

Keep in mind that in the schematic are no fuses and kill switches. Surely they will be add in the installation.

The normal use during driving will most likely draw only 2-4 kW in total. But the system has to be capable of maintaining 6kW to both engines over a couple of hours if necessary.

Left Option like Page 19 at wiring unlimited "Diagonally":

Pros:

- should make equal current on all banks

- only one battery monitor (shunt)

Cons:

- horrible long cables, about 28m for each + and - cable to the bus bar. Another 9m for each engine (just 125A)

- a couple of volts drop even with 120mm2 cable

Right Option like Page 19 at wiring unlimited "Busbars":

In this case the cable itself is the busbar.

Pro:

- shorter cables

Cons:

- 4 batteries in Victron System (not a problem at all, monitoring will be through (modified) MarineMFD App on a Raymarine MFD)

- unequal usage of batteries
- batteries in hulls will be discharged faster and get less charge than center batteries!?

I think (hope) last point shouldn't be a problem when laying on anchor the banks should be equalling themself, right?

Anyone tested this?

I also had the idea to build real separate banks and use Orion 48/48 to charge the banks for the engines. But the Orions are really getting only near 90% efficiency and I think that is a bit to much inefficient as the engines will be the biggest consumers.

Schematic:

[image]

Hi everyone

I have a Deye 12kw inverter that uses 10x Pylontech 3000C batteries and is connected with a 250A fused disconnect. Because of the limitations of the Pylontech battery cables I want to double my charge rate to 200A. Can I use the Victron Power In as a busbar without fuses using the fused disconnect that I already have or is it better to remove the fused disconnect and modify the Power In to take fuses or buy something like the Lynx Distributor?

Thanks

Can the Lynx Distributor (LD) ground nut be used for multiple ground connections like a bus bar, and then earth ground that connection to my AC service panel. I have a Multiplus II, MPPT Charge controller both chasis grounded on the LD grounding lug. I want to add my battery ground to the LD ground nut and then earth ground the LD to the grounding bus bar in my AC service panel. I'm following local codes but want to be sure this is a permissible connection. Also, I'm using the SmartShunt, would I ground the neg bat terminal or one of the terminals on the shunt instead. Thank you, any insight or opinions (regardless of code) is appreciated.

Hi,

I'm planning out a system for taking a house off-grid, using 3 MP2 10k's in 3-phase (I want to be able to power a Level 2 EV fast charger at full capacity (3-phase, 22kW total)

Can I safely use Lynx Distributors as my busbars, with their listed current rating of 1000 Amps? It doesn't specify whether that's continuous or peak.

By my math, fully-loaded, the multipluses will each draw 8000 Watts continuous, worst case system voltage of about 40 Volts (low SoC and 5 volt voltage drop) gives around 600 Amps continuous, which should be fine for the Distributors.

But, the MP2 can peak at 18,000 Watts for <0.5 seconds (https://community.victronenergy.com/questions/4454/peak-power-of-victron-inverters.html). During that time, assuming a worst-case scenario (all 3 peaking at once, low SoC, 5 volt drop), current would be about 1,350 Amps.

Can the Distributors handle that? I wasn't able to find a separate peak and continuous rating for them, only 1000A.

My understanding is that there's no way to limit the current the MP2s draw from the battery when AC in is not connected, other than by turning loads off. Is that correct?

I don't ever expect to actually hit that peak load. Is fusing the busbar's connections to the batteries/mppt controller (which I'm obviously going to do either way) at some point below 1000A total sufficient to make sure the system is safe, if I would ever exceed the 1000A draw from the MP2s?

Thanks,

Joseph

Tried to download the manual for the Lynx Distributor, to ascertain if this protect has any ratings suitable for marine environments, only to experience a browser crash. Does this product have any certifications such as:
-ISO 8846 ignition protection, and SAE J1171 external ignition protection requirements.

-Test standards include SAE J1171, External Ignition Protection of Marine Electrical Devices and UL 1500 , Ignition Protection test for Marine Products, and USCG electrical system requirements in Title 33 CFR 183.410(a).

Looking to possibly use this in a Diesel environment.

Thank you.