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Fuse monitoring with Lynx distributor and Lynx Shunt

Hi all,

According to what I've read in the manual for the Lynx Distributor, it is not possible to get blown fuse information across VE.CAN unless there is a BMS in the system; i.e. a Distributor + a Lynx Shunt will not produce the required messaging to the GX interface panel. Is this really correct? What a huge missed opportunity if so.



chris-3 asked
svenmueller commented ·

1 Answer

Fuses and Earth of the DC side of 3-phase system

Hello, how to understand the "It is essential the negative battery terminal between the units is always connected. A fuse or circuit breaker is not allowed" in the Multi II Manual? The interconnection between the units is meant? The BMS in error case disconnects the minus pole of the battery by N-MOSFETs, there is no way to do it in other way. And the DC terminals of the Multis see no difference (except of the stray capacitance) which pole is disconnected. Is it correct to earth the plus pole of the battery and insert the fuse and the DC switch into the minus line which can be interrupted by the BMS anyway? Thanks.

Anton asked
Alexandra commented ·

2 Answers

Easysolar II gx: solar array, fusing and grounding

Hi! I’m a bit of a solar energy newbie, trying to install a 5000w off-grid system. I’ve got the Easysolar II gx 5000 which has the MPPT 250/100 inside, 10 Trinasolar Vertex 505w panels and 3 Pylontech US3000c batteries. I thought it would be simple to connect but I’m struggling a little with the following question. Would greatly appreciate your opinion here!!

1. How do I best connect these panels? I now realise with 10 panels I bought a silly number. 2 parallel series of 5 panels exceeds the 250v limit (Vmpp 43,0, Impp 11,75, Voc 51,9 (- 0.25%/°C), Isc 12,35 (0.04%/°C). 5 parallel series of 2 panels leaves me with a very high current, probably needing a quite massive bar to connect them and thick cables (am I right here?). I’ve used the online calculator and it says 5x2 is okay though. What would you do? Or shall I rather put them as 3x3 and leave one panel off or buy 2 more and make 3 parallel series of 4 panels. This would potentially give me over 6kW PV array, whereas the manual says max 5.8kW, nevertheless the online calculator says it’s okay.

2. How do I fuse the system? So far my understanding is that best practices would be:

* One 20amp DC fuse (this is the panel’s max series fuse rating) for each parallel series of panels to avoid too much current flowing in from the other strings in case of short circuit.

* From there I lead the parallel series together and add a DC fuse/switch before going into the Easysolar. Am I correct in understanding it should be a 70amp fuse as the MPPT’s max PV short circuit current is 70A?

* Should I add a DC fuse/switch to the batteries? I’m off grid so I normally won’t want to disconnect the batteries unless I need to replace them. The manual says the recommended fuse is 200A, just for my understanding why would it be this high if the max output current is 100A?

* I will connect de AC out to my small house the house has a regular fuse box in place with a 32A main fuse and after this, several groups for the different areas with 16-20A fuses. I assume I don’t need to change anything here?

3. How do I ground the system? My house is grounded from the main fuse box, so every plug etc has a ground wire coming into the fuse box and one thick wire goes to the pin in the ground.

* Should I add a ground wire from the chassis of the Easysolar directly to the same pin?

* Should I add a ground wire from the chassis of the solar panels to the same pin?

* Should I add the ground wire in the AC out and where does it go? Should this be added to my house’s grounding system or should it replace it (ie instead of my house’s ground wire to the pin, I redirect it into the AC out of the Easysolar (and the Easysolar redirects it via the chassis to the pin??)

* Do I need to add any grounding to the batteries in any way?

Many questions, I know! I hope someone of you is kind enough to spend her/his precious time in writing me an answer and I also hope this may help others who may have similar questions. Thanks so much in advance!!

joeriwa asked
joeriwa answered ·

5 Answers

DC consumer fuses/breaker

The Wiring Unlimited guide says that all DC consumers (load) need an individual fuse. I have about 10 DC consumers that I was planning on splitting into 3 groups and have an appropriate sized breaker for each of the 3 groups. Is this sufficient, or do I still need fuses on all 10 individual consumers? Also, is there any disadvantage to have the individual fuse right after the positive comes off the positive bus bar than directly before the load (consideration for changing blown fuses)?

adrianp105 asked
christern answered ·

2 Answers

what size fuse between 200w solarflex panel and MMPPT 75/15 smartsolar charge controller

I have an Ampere Time 12v 200Ah battery
Renogy 2000w inverter
all for my tow trailer

One of your other replies was 15A DC rated circuit breaker or a 15a PV fuse with disconnect switch.

Many thanks

orangecowboy asked
orangecowboy commented ·

1 Answer

2 Answers

Do I need a fuse and or circuit breaker?


I’m new to solar and have a question on to fuse or not.

I have a fish pond that I would like to run the equipment on solar.
I purchased a Victron BlueSolar 115W panel, SmartSolar 75/15 controller, and 130Ah LFP.

Please excuse my ignorance, should I be using a fuse or circuit breaker in any part of the installation, also can I store the battery and charge controller in a partially buried (adjacent to small fish pond) watertight container or is ample air circulation required?


mark-allen asked
orangecowboy commented ·

1 Answer

32v mega fuse compatible with 33-34v operational voltage?

I’ve got a nominal voltage of 24 for my off grid solar system but the operational voltage at full capacity will ideally be between 33-34v. Will 32v mega fuses work?

dragon-wagon asked
elf44 answered ·

2 Answers

Fuses Logic Help


My logic, that might be failed... says that your fuse at your battery, should be a bit lower Amp than the internal fuse of your phoenix inverter, so it will blow first before your internal fuse? Please give some input.

I have a 12/500 Phoenix, with 3x35amp internal fuses. Going to connect to a 105amp battery, with 10mm-square cable. What fuse do I need at the battery to protect the inverter?


finhobbyist asked
finhobbyist commented ·

1 Answer

Will the Fuse LEDs on Lynx Distributor illuminate without the 4-pin cable supplied with unit?

Trying to use the Lynx Distributor (and Power In) without the Lynx Ion Shunt or BMS (using BYD batteries). I had assumed the Fuse LEDs would illuminate with a working fuse in place and powered, however a line on the old Victron Live page for DC Distribution Systems suggests that this small data cable is used to power the LEDs (rather than taking power from the busbar itself). I cannot get the LEDs to illuminate - are the LEDs useless unless using the Lynx Shunt? Because Lynx Shunt uses CANbus, it cannot be used in conjunction with BYD on a CCGX (though I think VGX would support it).

midsummerenergy asked
rikhf edited ·

7 Answers

Phoenix 12/500 Fuses


My brother has a Phoenix 12/500 inverter. It has 3x35Amp internal non replacable fuses.

1. What Amp fuse must he use on the battery cable with a 105Amp battery?

2. If one of the fuses on the 12/500 blows; is the inverter then dead? (why 3 fuses)


finhobbyist asked
Alexandra commented ·

1 Answer

Welche Sicherungen werden für den Lynx Distributor benötigt


aktuell ist ein Multiplus II 48V/5000 mit 4 x Pylontech US2000C im Einsatz (der Multiplus liegt parallel zu einem alten SMA SunnyBoy PV-Inverter mit max 3kw).

Nun soll das System um einen MPPT Laderegler erweitert werden (weitere 4 Solar-Panels mit je 400W werden installiert).

Als Laderegler wird ein Victron MPPT 150/45 installiert.

Um nun die Systeme zu verbinden, soll zusätzlich ein Victron Lynx Distributor installiert werden.

Meine Frage wäre nun:

Welche Sicherungen sollten in dieser Konstellation im Lynx verbaut werden. Am Lynx werden angeschlossen:

- Victron Multiplus II 48V 5000

- Pylontech Batterie-Rack (4xUS2000C) mit in Summe 4 x 9,6 Kwh

- Victron MPPT 145/50

Aktuell angedacht bzw. mit empfohlen wäre (jeweils als Mega-Fuse 70V):

- 60A für den MPPT

- 100A für die Pylontech

- 200A für den Multiplus II

Ist das so passend? Die vom Multiplus scheint mir etwas zu groß zu sein, oder?

adahmen asked
mike4nl answered ·

2 Answers

Guest Cabin gets all the solar

Hello! I am building a small guest house (195 square feet / 18 sq meters) behind my home, and want to add a system like this:

*Tied to grid via 30 amp shore power plug-in similar to an RV, but don't want to feed the grid

*Guests can stay and enjoy life 'off grid' using solar and battery, and if battery gets low or there is a need to use appliance that requires more than batteries can provide, just plug in shore power

*If my home loses electrical power temporarily this is a type of backup shelter

I'd like to use Victron components. Based on my initial research is this ok?

1/ two solar panels on roof

2/ Victron MPPT 100/30 charge controller

3/ Victron Multi Plus Compact 12/2000

4/ Victron’s Venus GX

5/ Victron's BMV-700

What kind of AC/DC panel (fuse box) is appropriate? Any suggestions regarding the specific type of batteries to use for this?

Thank you for any advice!

goteborg asked
snoobler commented ·

1 Answer

Victron Mega Fuse slow blown issues

A 100 amp Victron Mega fuse blowns at 250amp accroding to this video (289) Testing 100A Fuses with 100A of current. - YouTube

I am concern then how to choose the correct fuse for a 100a wire capacity, a 60amp?

sebastianlehmann asked
tom4x commented ·

2 Answers

Do I need to add a fuse between 2 Controllers that are connected to a battery that already has a fuse on the positive wire?

This is my planned install for the 2nd controller and a 2nd panel to my camper. The two controllers will be connected to a bus with no fuse.. Is a fuse between the controllers and the bus needed If I already have a fuse between the bus and the battery?


tomgiar asked
Kevin Windrem answered ·

2 Answers


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