fuses Image


Tinned copper

In environments with high humidity e.g. on a sailing vessel at sea we see a lot of corrosion at connections with metals with dissimilar potential.

In the presentation of the Victron fuse holders there is mentioned tinned copper bars with stainlesssteel (hope it is A4) bolts and nuts (rings)

These are materials with quite a different potential, isn't better to use tinned brass nuts bolts and rings.

Peter Buijs - NL asked
Peter Buijs - NL edited ·

0 Answers

Fusing/Breaker confirmation and general system guidance


I've bought most of the stuff in this setup and now want to get fuses/breakers. But wanted to run it past those in the know before buying. Any comments on the above diagram would be welcome too; sizing of the wiring to follow when i've measured. Also does anyone have any recommendations on breakers/fuses?

rolandchart asked
seb71 answered ·

1 Answer

Installing IP22 battery charger

Hi there. Can I use a AWG 11 (4 mm2) wire to connect the IP22 12V/30A to three 74 Ah/680A wet batteries, at a maximum distance of 2,5m? Also, shall I install fuses between the charger and the batteries? If yes, how many Ampere? Thank you in advance for the hints. Max.

massimo asked

0 Answers

what size fuse do I need between MPPT 150|35 Victron and my battery bank

what size fuse do I need between MPPT 150|35 Victron and my battery bank? (battery bank is 400aH 12V (2x 200aH)

herwig-maurer asked
David Ferguson answered ·

3 Answers

Why do my fuses keep popping

Hi there , hopefully someone can help me figure out what's wrong with my setup and why my 40amp fuses keep popping. It seems to be only the fuse on the positive cable that keeps popping.

My setup:
MPPT 150|35 Victron smart solar charge controller
BMV-712 victron smart battery monitor
2 x Renogy Deep Cycle Agm Battery IN PARALLEL - 2x200aH = 400aH @ 12V
• 2 x Renogy Solar Panel 160 Watt 12V ( if I connect only one, the problem still persists but seems to happen less frequently)
• 1500W erayak inverter ( fuses keep popping when this this turned off, so I don’t think this device plays into the problem)

According to my (novice) understanding the fuses should not be popping continuously.

I’m afraid to just disconnect the fuses, yet maybe I don’t even need them? Would it damage my MPPT if I disconnected them?
I appreciate any advice!

Thank you in advance!

herwig-maurer asked
herwig-maurer commented ·

2 Answers

battery input shorted - fuse constantly blowing

I have had a successful small solar setup with the Victron 100/20 Bluetooth enabled controller and three 100w panels in series to make 60v PV input and 80AH worth of lithium-ion batteries and so the highest voltage charging was set to 12.5v, this setup lasted about half a month with no problems. I come home today to a blown fuse and the battery terminals shorted to almost 0ohms. I can still access the controller from Bluetooth and resetting to factory default changes nothing. when i checked the history tab on the controller the highest PV voltage was 126v and considering three 20v panels in series can not possibly create that much i feel inclined to believe it may be defective - although checking the current voltage still says 59v... any help would be appreciated

Shamus Ploegman asked

0 Answers

what fuse size for the 12/5000 quatro

hi im running 4 300ah 12v lithium batteries.

directions recommend a 800amp fuse.

peak discharge 3000amps 5 seconds

discharge 100 amp

manual calls for a 800 breaker

i am having a hard time finding a holder/block

can i use a 400 amp. also what types of fuses are ok

using 5 feet x2 120mm wire

ahearnkevin asked
seb71 answered ·

1 Answer

tripping a fuse after solar Changer

I recently installed four 300W solar panels on my RV. I'm using a Victron smart Solar charge controller MPPT 100 / 50 that is protected by two 60amp fuses on both sides of the positive line. The 60 Amp fuse that is exiting the Solar Charger and going to the Victron Multiplus 12/3000 keeps tripping. I was pulling in around 650 watts from the solar panels. The 4 solar panels are wired in Parallel. the wiring on the Solar Charge and fuses is 6AWG. I don't think I was bringing in any ware near 60amps so I don't know why the fuse was tripping. Is my fuse not big enough? Thanks much!

overland asked
michelg answered ·

4 Answers

Orion-Tr Smart 24/12-20A (240W) Isolated DC-DC converter: External Fuses

Hello community,

Orion-Tr Smart 24/12-20A (240W) Isolated DC-DC converter: External Fuses

I am confused about external fuses required in a system with the above device.

The spec shows 25Amp maximum current under nominal operating voltage and 50Amp short circuit on the 12V output channel.


But the fuse advice in the manual is for 30 amps on the 24V channel and 60 amps on the 12V channel - surely these are too high?


I am specifying the integration of this component and am looking at advising 25Amp (24 volt channel) and 50Amp (12 volt channel)

Any confirmation would be appreciated.


andrewg asked
radman edited ·

3 Answers

Maximum battery charging current of a SmartSolar 100/50 charge controller

What is the maximum battery charging current that I can expect from a SmartSolar 100/50 charge controller?

I very recently installed this charge controller and placed a 50A circuit breaker between the charge controller and the battery bank.

I'm discovering that my 50A circuit breaker is tripping between 11AM and 1 PM now that the sun is getting higher in the sky. When I check the state of the charge controller, I am getting over 550W of solar production and the current is around 45A. So far I have never seen a current reading over 45A.

I'm thinking my circuit breaker amperage rating is too low.

The wire size from the charge controller through the circuit breaker to the battery bank buss bar is 6AWG. 6 gauge was chosen because it was the maximum wire size specified in the Victron user manual.

All the battery cables within the battery bank and smartshunt are 2 gauge.

The maximum current specified for a 6 gauge wire is specified to be 72Amp.

I'm thinking about using a 60A fuse but would like to know what is the maximum current the smartsolar 100/50 controller can provide before making a final decision.

hhaley asked
alan edited ·

3 Answers

12/12 30A Orion-Tr Isolated Smart in parallel fusing recommendations

I am new to 12V systems and am currently specing out / purchasing components for my 2020 4x4 sprinter conversion power system. I have purchased 2 x 12/12 30A Orion-Tr Isolated smart units since I am looking to obtain 60A charging capabilities. I am building a 12V 400Ah battery system. I see the fusing recommendations are 60A at the starter battery and 60A at the auxiliary battery side, this is however in the case of having a single 12/12 30A Isolated unit.

What would the fusing reccomendation be for two units in parallel? do I fuse / circuit breaker them separately effectively having 4 fuses configured? If not I would appreciate any documentation links or schematics I can refer to. Any input is appreciated!

So far I am using Blue Sea Systems components for Bus Bars, Battery Switches and Circuit Breakers.

karol-kozubal asked
d-winterburn answered ·

2 Answers

MIDI vs MEGA fuse voltage drop / power loss

I'd have expected physically smaller fuses to have greater power loss than larger fuses - that is, a MIDI fuse to have greater voltage drop than a MEGA fuse of the same rating.

However Victron's MIDI, MEGA and ANL fuses, and fuse holders data sheet says otherwise: https://www.victronenergy.com/uploa...,-Mega-and-ANL-fuses,-and-fuse-holders-EN.pdf

e.g. MIDI fuse 100A = 60 mV (= 6 W @ 100A); MEGA fuse 100A = 90 mV (= 9 W @ 100A)

I'd love to hear if anyone has any practical experience that can confirm or deny Victron's publication.

benl asked

0 Answers

Multiplus 12/3000 reste éteint


Aux bornes de l'entrée batterie un voltmètre indique bien 12 volts produits par des batteries neuves. Aucunes LED ne s’allume ni le "digital multi control"

Merci de me faire participer à votre savoir.

duplantier asked
Carrara Frederic answered ·

1 Answer

Is it possible for a fuse to half-blow? [Answered]

In the interest of furthering the knowledge base this Community provides, I'm asking a question here -and will post the answer below- that I receive not infrequently when assisting Victron (and other) customers with troubleshooting their various devices and ask them to check the fuse to ensure that it's not blown or half-blown:

"Is it really possible for a fuse to half-blow? I've never heard of that!"

Justin Cook - Bay Marine Supply USA asked
ttbb answered ·

4 Answers

ANL fuse prices / quality

Is there a difference in quality between various makers of ANL fuses? I see single 150A fuse prices ranging from $5 to $25. Does brand matter or are they all the same? (Other than some being ignition protected, some not.)

Also, the Multiplus manual recommends 2x pos and neg cable connection. Should each positive cable be fused for 50% of total current expected?

texascharlie asked
Daniël Boekel (Victron Energy Staff) answered ·

1 Answer

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
mark-allen commented ·

1 Answer

Lynx Shunt 1000 with Lynx Distributor 1000


I've recently design a setup with 4 x 12V 200A Smart LiFePO4s in parallel connected directly to the Lynx Shunt 1000. The Lynx shunt is then coupled with a Lynx DC Distributor 1000 on its RHS. Connected to the Lynx DC Distributor is the Victron 12V 5kVA Quattro Inverter and DC loads.

Is it ok to connect the batteries directly to the Lynx Shunt 1000 and the fuse within the shunt can be used as circuit protection for the batteries?



nic-sama asked
nic-sama edited ·

0 Answers

Lynx Distributor Usages Clarifications

Hi All, my first time with Victron products and Solar Energy. Questions about Lynx Distributor. Considering that has 4 slots fused.

1) May I connect the whole system in One Lynx Distributor Unit?.
Slot 1: Multiplus-II 48/3000 (Fused)
Slot 2: SmartSolar MPPT 250/100 (Fused)
Slot 3: Lithium 48V Pylontech US3000 (Fused) (3 parallel modules connected with cable kit 120A/2000mm lenght)
Slot 4: Venus GX (Unfused as brings its own in-line Fuse)

2) Fuses sizing should be MEGA 125A for all 3 Slots? (i.e. Littlefuse MEGA 125A/58V for 48V)

3) Is there a minimum lenght for Cables of Slot 1 and Slot 2, I have available AWG2 35mm2 nominal cable (33,6mm2 actual section). For Slot 3 cable kit size came Pre-Fabricated.

Please if you see any safety issue advice, this is an Off-Grid system. 3000W Panels Array (4series x 2 strings). (SmarSolar is oversized for future expansion duplicating whole system)

Thank you,


sanchuka asked
maxxpwr answered ·

2 Answers

Fuse size for MPPT 100/50

I’m installing a mppt 100/50 in a van build. I have 3 -180 watt panels wired in a series. I have a 15amp dipole disconnect between mppt and the panels but what size fuse should I use between the busbar and the mppt? I was guessing 75amps or 100??

tahoematt asked
Vance Mitchell commented ·

1 Answer

200ah Lithium Fuse Size

I can't find anywhere in the manual on fuse size recommendations. Based on the specs I would assume a 200a inline mega fuse would protect the 200ah lithium battery (and cable--at 35mm2 with a 1m run), would this assumption be correct?

stephenb asked
nebulight answered ·

2 Answers

Warning: Solar Newbie question... Fuses/Breakers/cable for my system

I am building a solar/battery portable system for emergency use. It is based on 4 Battle Born 12V batteries, in series pairs and parallel for 24V, 200AH total. I am using a Multiplus 24/3000/70 Inverter Charger and a 150/85tr Solar Controller (This is being upgraded to a 250/100, due to your comments. Thank you!). I will also be using a Victron 24/12/40 step down converter for 12V loads, which I expect to be few but thought I should account for, nonetheless.

I need to protect the systems with fuses or breakers, but am having a time determining the proper amp ratings, and exactly where to place them. Diagrams I have read don't agree, so I am guessing there are many ways to do this.

Can someone help, or provide a reference to information that would shed a little light on this subject? I am not totally new to electricity, but am new to solar powered systems and am not ashamed to ask for help when I need it. I'm not going to connect a wire until I know what I am doing!

Thank you in advance...


I am including a diagram I did today showing the items I have (except the breaker on the Pos battery line, that one is a guess), and how I envision them to be connected. I have a feeling more fuses or breakers are required, and I am totally open to comment or suggestion on cable sizes or other needed additions or changes.

UPDATE 5/27:

Drawing updated to show upgrade to Solar charge Controller, per comments. Also added a slight upgrade in 24-12 converter capacity (40 to 70).

System Drawing V4 5-27-2020.pdf

rickp asked
rickp answered ·

2 Answers

Self resetting fuse for charge controller

I am wondering if anyone has used self actuating or self resetting breakers for the positive line from charge controller? Any downside to using these instead of manually resetable breakers?


mrcc11 asked
Matthias Lange - DE commented ·

1 Answer

Multiplus II connection to Pylontech via FUSE?


i plan to buy a MultiplusII and US3000. From the schemes i have seen there is no external fuse in between both devices. Is there something already in place in one of them or even in both? I guess so for securtiy reasons.

Furthermore.....if not and its highly recommended....what kind of fuse is used, i have no idea how this looks like.

I'vr read somewhere that they uses a 125A fuse.....i guess for the 5000. As i'm using the 3000er - and will limit the output to 1000W....does it make sense (if you say its required to have one) so take a 32A (if it exists) .... as i will not go higher.

Kind Regards,


njordan asked
njordan answered ·

2 Answers

15.t volts going to battery from charge controller

Hi. So when my mppt 75/15 is sending 15.5 volts to my battery. Which as now happened on 3 occasions. Why hasn't 19amp fuse blown on the cable going to the battery. I can only think the last time it happened. The chatge controller was in the garage. Once it warmed up it worked as normal and went to float after a while. And didn't go above 14.2 on volt meter

Steve asked
Steve commented ·

3 Answers

24 Posts
49 Users

Topic Experts

There are currently no experts identified for this topic. Can you answer questions in this topic area? Community members who provide answers that are marked as correct earn reputation and may become recognized as topic experts.