Victron Batteries, Lynx Smart BMS, Distributor, Cerbo GX, and connecting a Multiplus II

[@stephengreen2898]

Wow… just found you…. Love your different angles & close up to wide camera views AND LETTING ME SEE/HEAR each STEP…. GOING TO SUBSCRIBE AFTER THIS 1 video

[@VanTransitions]

Thanks! I too am a visual/hands on learner.

[@anthonyg9787]

this video helpss alot.. have a step van and putting lynx and multi plus ii with cybro gtx and all ...

[@VanTransitions]

Glad to hear, thanks, and enjoy your project!

[@maingey1]

Great vid mate!

[@VanTransitions]

Thanks!

[@mathewneenan1673]

In the few videos I watched, the Multiplus is always connected to the left-most posts and here you did the same thing. I also read this on a couple forum posts. However, I could not find any official documentation stating that this needs to be done. I've already set up my system with the multiplus connected to the right-most posts, simply due to positioning and space constraints. Now I'm a little concerned, however I've already created the 4/0 wires exactly to fit where they are. Should I leave as is or should I be re-engineering my layout? Thanks, and great videos! Yours was the only one I could find on hooking up a Blue Sea breaker panel, very helpful!

[@VanTransitions]

I put my MPII where it is b/c it was my first and largest component I installed into the system. I don't see why it would matter what slot you use on the LynxD.

[@boydbros.3659]

Thank you for this!

[@VanTransitions]

You're welcome! Make sure to check out the MPII ground correction so that is not undersized.

[@robertmuckle2985]

I would personally not allow my 4AWG battery 2 battery terminal wire to be straight as yours is. I would prefer a slight arc in the cables to allow some movement and accommodate vibrations etc. Yours are basically solid hard wire from RTC to RTC which could cause them to work loose over time. A slight curve would let them ebb and flow at the cable and not just tug of war on the RTCs. Just my 2cents. Cheers

[@VanTransitions]

Hi. The battery to battery cable is 4/0 (4 ought). At that short length there is virtually no flex at all in the wire. My batteries are also locked down and do not move in any direction.

[@robertmuckle2985]

Exactly my point…”there is no flex at all in the wire”, therefore the cable and terminal lugs are constantly under stress with each other and will vibrate loose over time, UNLESS your batteries are 100% rigidly fixed to one another. I’m not confident this can ever be the case in a mobile scenario. A slight bend will relieve this inherent stress. You’re fine in an off grid fixed setup…but not in a mobile application.

[@VanTransitions]

While a well put together system should not have this problem in general, yes, a van is a moving earthquake, and therefore ANY person having a house system in their van should have a regularly scheduled interval to check on all wiring and bolts to ensure healthy, tight, clean connections.

[@jaredsimpson3798]

Two questions: Why did you not power the Cerbo gGX from the Aux ports on the Lynx BMS? Why did you use a fused busbar access pount for the MultiPlus case ground, instead of using the far end of the Lynx Connect?

[@VanTransitions]

You are referring to section 5.4.8 here www.victronenergy.com/upload/documents/Lynx_Smart_BMS/109358-Lynx_Smart_BMS-pdf-en.pdf which is perfectly fine. I didn't feel like cutting the ring terminals off, lazy I guess, haha! The MPII case ground is on the neg bus middle post of the Lynx Distributor. It is not one of the 4 fused posts on that bus.

[@AlfonsoMedina-x6u]

Much appreciated your video! Plan to duplicate same setup in my garage before final installation. Do you have schematic drawings for my reference? Nothing fancy-a manual drawing will be ok. Thank you.

[@VanTransitions]

Thank you for the compliment. I am not an EE (Electrical Engineer) so I do not feel I should share my drawing. All designs should be validated by your Victron distributor and/or an EE before implementation. I will note I believe my chassis ground is on the wrong side of the Lynx BMS. It should be on the functional side, not the battery side.

[@ponchitmedina4936]

I understand … Other than reading the Victron webpage, any books you can recommend?

[@VanTransitions]

If you need a basic understanding of electricity, start there. DC and AC and the specifications will depend on what part of the world you are in. I did all my research online. I began with a basic knowledge just from life's experiences so take into account what you know and what you want to know and start searching and reading. The more you learn the more specific and targeted your search queries will be, then one day poof, you will feel well versed on the subject!

[@scrogathon]

What brand lugs did you use? I just recieved some 4/0 5/16" lugs and they do not fit correctly without needing to modify the plastic wire guides.

[@VanTransitions]

Should be these: a.co/d/fz5aMEL Do you have a large crimp tool for this size wire? I used this a.co/d/4Tv7ECW and show crimping here: kzbin.info/www/bejne/fHfNi6yMm8mpoLM All the best and thanks for watching.

[@WiSeNhEiMeR-1369]

Thanks COOP ...

[@VanTransitions]

Thank you!

[@LeuciRacing]

What gauge wire are you sing on the batteries and connected to the lynx? Is that 2 awg? Or 2/0?

[@VanTransitions]

Battery to battery, batteries to Lynx, and Lynx to MPII are 4/0.

[@jeroenbonamie8311]

Hi, Shouldnt the ground wire on the Multiplus be the same size as the incoming Dc wire? Thanks in advance.

[@VanTransitions]

I personally understand that as being 4/0 for system chassis ground. I cannot fit 4/0 lugs into the hole for the MPII chassis ground, let us know if you can. Make sure there is a distinction between the MPII chassis and system chassis grounding. Please check with your Victron Dealer and/or electrical engineer before applying anything you see here to your system.

[@OldExodus]

Hello, Does it matter if the Lynx Distributors are on the connected to left side of the Lynx Shunt? I always see thr Lynx Distributors connected to the right of the Lynx Shunt

[@VanTransitions]

Hi. Check out the Victron Energy Lynx Distributor manual. There are use cases for either side of the Lynx Smart BMS 500 which has a shunt in it, which is my use case. If you are not using the BMS 500, design the system per your use case needs, but based on that documentation, I'd say there are use cases for either side of the shunt.

[@wanderingzythophile9083]

Couple of questions for you! 1) You mention having used 10/3 wire into your MP and then swapping to 8/3. You talked about the connector and ferrule issue, but I don't think you actually specified that was the reason you went with the larger cable? It's my understanding that 10/3 is plenty for a 30amp shore power connection. 2) You've got a 6awg cable acting as your ground between the MP and the Lynx - other install videos I've seen have used much beefier cables for this. Is this just a temporary solution for testing purposes? I'm just at the start of building up a largely-Victron system for my van so finding your channel this morning is quite timely :) Thanks!

[@VanTransitions]

It is also my understanding 10/3 would be good for a 30A shore power connection. Due to my issue with the ferrule, I went larger to get things going and feel more confident when pushing the wires into the slots. I'd really prefer screw terminals. I may go back to the 10/3 from the back of the SmartPlug from shore power to the MP-II AC in for my final install in the van. The more you practice using the tiny screwdriver to open up what "should be a push in terminal" the more easily you can insert your wires. Not a great design by an industry leader in my opinion. Good observation, yes, I should have said the 6AWG ground cable is temporary. 4/0 will not fit in this location which is the size of the main DC power feeding cables. ABYC recommends the case ground be no smaller than 1x size down from the main current carrying conductor. I have some 2/0 on the way and hope it fits without fuss. 4/0 on a lug will not fit here straight in via the provided chassis hole of the MP-II. It would with a right angle lug through the larger pill sized hole, but if you have all 4 DC inputs used, then I don't think there would be a place for the ground wire to fit through that pill hole. I will highlight the chassis ground wire in a future video when I talk about AC in and AC out to a 120V panel. Thanks for the compliment. I'm learning as I go and sharing what I can. Make sure you verify your wiring diagram with your Victron dealer and/or an electrical engineer. I am still having some back and forth discussion with my dealer on a couple very explicit details in my wiring plan.

[@VanTransitions]

The chassis ground is noted in the video description :)

[@wanderingzythophile9083]

Gotcha, thank you for the reply! I've got a MP 12/3000/120 unit, which should accomodate a 4/0 lug for the ground, but that's good to know about the MPII and also the one-size-down rule of thumb. Those green connectors aren't exclusive to Victron, I've recently learned. "Phoenix connectors" seem to be the usual name. I figured this out when I discovered I misplaced the little green plug that came with my Orion... :/

[@VanTransitions]

Ah, yes, I think the MP (not the MP-II) has a much more easily accessible chassis ground stud location.

[@HumbleRoad]

Chassis ground should be one AWG size smaller than the feed wires. So in this case, 3/0 wire would be necessary for the chassis ground. Personally, I use the same 4/0 for chassis ground.

[@MrPeterJMilner]

Hi, So if in the manual, the Multiplus II calls for a 400 Amp fuse, which is what youve got, why have you underspec'd the input into the distributors with a 300 Amp breaker and fuse behind the batteries? I have a similar system on my boat but have spec'd the system to be rated at 500 Amps, therefore allowing 400 Amps for the Multiplus II and 100 Amps spare headroom for all other loads.

[@VanTransitions]

Here is my philosophy (and my Victron Dealer OK'd my spec): 300A (red on/off) allows up to 3600W at 12V. The inverter should only be running at max 3000W (and my DC loads are otherwise quite low except the 12V AC at 80A max). Now plug in shore power, with Victron Power Assist, I get power from shore (15-30A), and draw power from the batteries if more amps are needed, so I allow more, the 400A fuse, to the MPII as spec'd. As expensive as these batteries are, I'd like to protect them and not risk them being the breaking point of my system. I'm not saying I'm 100% right, but hope that helps you. Thanks.

[@laurentsosson1739]

Hello and barvo for the video I wanted to ask you if it is possible to install the bms from victron (16S for a packlife that I have in 48 volts? 600AH)? or do you have to have a victron battery? my batteries are EVE 280AH in 16/2P can we wire all the batteries with the bms from victron or do we need a bms compatible with the victron? otherwise is it possible if there is no can in the battery pack to tell victron (multiplus and cerbo GX) that I have a lead gel battery pack? there is no bms on the lead in general? my pack can be protected by its own BMS cutoff 2.80 volts and maximum charge at 3.65 volts Possibly just to emit more or less on the multiplus? thank you laurent

[@VanTransitions]

Thank you. Unfortunately I'm not sure what advice to give her other than to recommend you talk to a Victron distributor or certified electrical engineer for your special case.

[@cujo7240]

I'm a bit curious as to why you went with the Victron Multiplus II 2x 120V 3000VA 50A inverter/charger for your 30A van build, since I believe there's a less expensive 30Amp version available? The Victron Multiplus II 2x 120V 3000VA 50A version was really designed for 50A split phase systems and all you would need is unit designed for a 30A single phase. Not trying to be critical of your build, just trying to understand your thinking on this. I'm in the research phase of a project like this for my 50A RV.

[@VanTransitions]

Fair question, a couple reasons. When I had the funds available to make the purchase, supply/demand was still a bit of an issue and prices were pretty close. And, while I haven't shown this in a video yet (it is discussed briefly in comments), I can wire it to use the Power Assist feature. I may be limiting myself to 30A shore power, but I can go up to 50A 120V AC main breaker before my AC panel and draw power from shore and batteries if I'm baking a cake, cooking dinner (induction), and remotely working at the same time (non 12V monitor). That's a bit out there as an example of load but I think that gets the point out clearly at about the max of a 3000VA inverter. Form factor played another role in the choice. Some MP units are fat. Also, given I am going 100% electric, I wanted power without question.

[@ArcticNorthAdventures]

I tried to find out what a 4/0 5/16 is in mm2 ? 4/0 is 120 mm2 but it seems not to be the size you used?

[@VanTransitions]

On which device in which part of the video? There are several places where 4/0 is used (120mm2 seems to be the correct conversion).

[@ArcticNorthAdventures]

@@VanTransitions Multiplus 2 to Battery or Smartshunt

[@VanTransitions]

MPII is connected to the Lynx Distributor by 4/0 then via that bus system through the Lynx BMS 500 to the batteries, also using 4/0.

[@ArcticNorthAdventures]

@@VanTransitions so its a 120 mm2 cable the 4/0 ?

[@VanTransitions]

All the googling I do, the conversion charts say 4/0 and 120mm2 are the correct conversion cable size.

[@christopherhiggins8238]

Question. What does the Lynx do? In about 2 weeks a friend is going to help me install stuff I bought 2 years ago... Disabled Veteran, PTSD and mental health problems...

[@VanTransitions]

Hi. In short, bus bars and locations for fuses. Best source is the vendor website: www.victronenergy.com/dc-distribution-systems/lynx-distributor

[@BlackRVer]

I have a simple question: Can you show how to wire up a dual 12/3000/120 Victron MultiPlus-II inverter?

[@VanTransitions]

Hi, can you be more specific? You have 2 MP-II inverters or a single with dual 120V AC? And what exactly are you looking for? If I have an example I'll point you to it. I will also say I am not an EE and I do not have extra equipment on hand. I have several videos which may help get you started related to how I plan to wire my Victron equipment in my van. Also, if you purchased your Victron equipment from a dealer, they should be more than willing to give you some pointers if they are a good dealer.

[@BlackRVer]

@@VanTransitions I am speaking g of using two (2) Victron inveters.

[@VanTransitions]

I would start here and also contact your Victron distributor: www.victronenergy.com/live/ve.bus:manual_parallel_and_three_phase_systems

[@BlackRVer]

@VanTransitions Thank you. I will start there. Loving the videos.

[@b3owu1f]

So.. question.. why 4/0 wire? I am looking at runnint 2AWG from my 48v/3000 to my lynx distributor, and 2AWG from that to the battery shunt, then to the battery system, which is 1 48v 16s battery (but will be a 2nd one soon). The battery cells are LEV60, able to handle a max of 600a. But I am only using it to power a couple of computers and a fan or room ceramic heater. So at most about 3000 watts at 120vac.. around 25amps total. So for whole house setups, I could see bigger wire, but for my setup since 2AWG can handle a bit over 100a, and I wont push more than about 30a total, I am hoping that is plenty of wire.

[@VanTransitions]

My video is based on running a 12V system. Wire size requirements will be different if you are running 48V. If you want to ensure you are on the right path, please engage your Victron dealer or a certified electrician.

[@michaelskeels4442]

The multiplus is quite noisey. Is it always like that?

[@VanTransitions]

I figure you have it under load and the fans are running as an inverter? I don't often hear it when it is charging. Check with your dealer to ensure your unit is working properly.

[@eastofindy]

What happens when you disconnect shore power while the MP2 is on? I have done this twice (50amp) and instead of picking up the load it blew the 400amp fuse. If I shut the MP2 off before disconnecting the shore power, I can then power it up on battery only without a problem.

[@VanTransitions]

I have not had issues. How is your MP-II configured? Is Power Assist required to run your load? How much load do you have running when you disconnect from shore power? There is a Victron Energy (English only) group on Facebook you could try or contact your Victron dealer. Hope that helps.

[@eastofindy]

@@VanTransitions only disconnected when getting ready to move to the next camp site. So, the only loads remaining should be refrigerator and some 12vdc items. I would like to have faith in it picking up the load if power goes out but, not so confident. I turned off the MP2, didn’t change the load and replaced the fuse, started and ran fine. 🤷‍♂️

[@himesjon]

How are you doing it 2 way when victron says only one way.

[@VanTransitions]

I'm not sure I follow, can you elaborate on your question?

[@robertstuckle6198]

Hello, did you install a Skylla i Charger with an Lynx BMS and a Cerbo? I have a few questions about the wiring.... Best regards Robert

[@VanTransitions]

I am not familiar with Skylla.

[@robertstuckle6198]

@@VanTransitions Hello, thank you.

[@vespagts7078]

Be very careful with those green push-in wire connectors; they have a habit of expanding & contracting and losing their grip over time. They are also susceptible to weakening from constant vibrations and shock movement against the wiring. I had it happen to my 2,800ah Winston battery bank when one of the 4/0 cables walked itself out and welded itself to the steel frame of the battery box. I don't know how it didn't catch my trailer on fire, but I was very, very lucky. I just picked up a 24v 3000VA Multiplus and chose to NOT buy the Multiplus II because of that and other issues where Victron cheaped out.

[@VanTransitions]

I am definitely not a fan of those push in connections. The spring does feel quite snug, but a camper van is effectively a moving earthquake. And they have places inside the unit to clamp down on the end of your wire, so it should not walk out. No 4/0 cables in those push in spots on the MP-II. 10AWG from my 30A shore power and 6AWG if I change from 30A 120V panel to 50A 120V panel are the 2 wire sizes I'll have in the push in spots.

[@evil17]

So, are these a fairly new connector type innovation by Victron? I thought they were all a screw in type. Being an Aussie on 240vac, i wonder if they send us screw in type connections that Victron specify not to use ferrules, but fine copper wire secured properly to spec. I believe this is another source of failure, when people buy CCA (copper coated aluminium) wire, not knowing it can have this type of issues of dissimilar metals with different thermal properties down the track & not being able to supply enough current under heavier loads efficiently. Sounds like a scary experience you had there, but I guess if it had the required safeguards in place, in reality such a short should theoretically pop a fuse, a breaker, or the BMS should be set to shut down (if one is attached) if the current draw is excessive, but there could still be a lot of arcing & fire potential before this happens, regardless. I have been considering a 5kw Multiplus II recently, so I may have to look further into this, thanks for this info. Cheers

[@VanTransitions]

I am not sure when Victron started using the push in style. As mentioned I find them to be a bit of a pain. I also use full stranded copper, and marine wire where I can, such as Ancor brand. I would personally not use aluminum. I'm not a EE but I believe it can get hotter and vibrate into a short in a poorly done installation; and a van is a moving earthquake (my use case).

[@evil17]

CCA wire is rubbish, I have used it as a cheap extension cord for external panels to keep my Ute camper fridges going and batteries topped up, but it fail in a short time, basically the aluminiun turns to powder inside the cable and starts to give trouble, low amps/volts etc, I noticed warm spots that were a bit lumpyish on the outside, hard to spot, but when I cut the cable it was like powder inside. Always use solid copper wire, CCA is crap.

[@JelleKei]

A big pack Lithium batteries should always be fused with a class t.

[@VanTransitions]

I do not believe there is an "always" to this rule. Some experts recommend it, some say it is not necessary. For those reading this, do what is best for your system and consult an EE if needed.

[@gazzahuck9766]

You were incorrect when you said your positive and negative were equal length. That does not matter. However. The cables from the bus bar system to each battery. Be it positive or negative. They should be equal length for example. Both battery positives to the bus bar system. In your case with 2 batteries. Linking the red across and the reverse linking for the Black across opposing sides of the 2 batteries provides both batteries with equivalent equal cable lengths for each battery. Three or more batteries. People must make all black the same length . And. All red the same length to the bus bar. If not. The batteries WILL become imbalanced very quickly.

[@VanTransitions]

"That's like, your opinion, man." - Lebowski --- Yes, equal length is important on the battery side. Quickly becoming imbalanced is subjective. And if someone cuts a 4/0 cable 1mm less in length than the other, the system will be fine. Home installers and most professional builders won't have robot precision.

[@mannyfragoza9652]

i dont get all this time and money if you dont have it connected to a solar system. Shore power is not solar ?

[@VanTransitions]

Hi Manny. This is a table top demonstration of the power system for a camper van build. I will have 600W of solar on the van roof via 2 Victron 100/30 MPPT (check the next video in this series!). I should have a video out soon about how I designed my roof layout.

[@mannyfragoza9652]

@@VanTransitions ohhhh ok thanks

[@mondotv4216]

That's not the correct way to install the AC wiring. There's a video on KZbin if you search. You strip back more of the outer insulation and leave a loop in each conductor inside the connection box. This takes the stress off the wires. Those push terminals are fine but you must strip back the correct amount of insulation so that the wire goes all the way to the back of the connector but the insulation doesn't get caught up in the clamp. If that happens it can cause a fire.

[@VanTransitions]

The pos, neg, and ground wires for AC1 input are all stripped precisely to the specifications by Victron. There is no need (and no room) for a loop inside the MPII due to the clamp on the full insulated wire, therefore no stress on the wires between that clamp and the push in terminals.

[@HouseboatRenovations]

all crimp lugs should be tinned NOT bare copper.

[@VanTransitions]

I suppose that's one opinion.

[@evil17]

There are different schools of thought on that idea, but tinning or soldering can add other problem issues such as stiffening of the joint making it more susceptible to vibration and cracking, it can also add flux and corrosion issues, on top of this it also adds dissimilar metals with different thermal properties for expansion & contraction rates, poorer connection potential and heating that can melt the solder allowing the joint to become loose and a fire hazard. If you cut a lug that is properly crimped it should appear as a solid metal bond with no air gaps. This is a problem with using CCA (Copper Coated Aluminiun) wire cables instead of pure copper and requires you to use a heavier guage cable, the two metals react differently to temp change and also react together and oxidise faster, dont use CCA cable as a cheap alternative ever in these systems, its not worth the savings. Will Prowse will tell you not to tin crimped lugs for the various reasons above. A professionally crimped lug should basically compress the two metals to what is known as a cold welded or fused joint, ie: they bond molecularly and virtually become one solid metal joint. Soldering and tinning has its place for smaller gauge wires but not for battery or heavy load cables. Aircraft electrical systems have very strict guidelines for making connections if they have to be soldered including preparation and configuration before hand.

[@kimnguutv9661]

💯💯💯💯

[@VanTransitions]

thanks!

[@thaomai4953]

What brand lugs did you use? I just recieved some 4/0 5/16" lugs and they do not fit correctly without needing to modify the plastic wire guides.

[@VanTransitions]

Mine came from Amazon or were included in kits from Explorist.Life. None of them had any plastic on them; they were all copper only.

[@himesjon]

This has been an issue the ones that selterm sell are 1-1.1” the distributer is less than 1” wide.

[@wadesansom]

​@@himesjon Can you just cut the lugs down to fit?

[@VanTransitions]

I'm not sure I would tamper with the integrity of the lug. Perhaps try a 90 degree lug coming in through the pill shaped hole? I haven't tried.