Victron Solar System - Configuration, Fire Protection, and Monitoring

DIY
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Hi All,

We will soon receive our solar system for installation, and before that I would like to confirm with you if you notice anything missing or potentially incorrect in the equipment list below. This way, we can address it before installation.

The system will be installed on a tiled-roof house near the sea (exposed to salty air and wind). The panels will be divided into 2 strings on the south roof.

The Victron equipment and the batteries will be installed in the garage (the garage is only 3 m away from the house, but it’s ~30 m away from south roof panels in terms of going down from the roof to the ground floor and then to the garage with wires + the main electric panel is right under the south roof). We are also considering adding a fire suppression system in the garage to protect the Victron equipment, batteries, and our electric car. Ideally, the system would first disconnect all power before activation.

We would like to confirm:

  • Would a water-based system inevitably damage the Victron devices (inverter, MPPT, Cerbo GX, etc.), even if power is disconnected beforehand?

  • If fully disconnected, is there any chance the equipment could be safely restarted after professional inspection and once fully dried — for example, if only one battery was affected?

Additionally, we would like your advice on alternative fire suppression methods that are safer for electronics, such as:

  • Aerosol-based systems (e.g., Novec 1230, FM-200)

  • Gas-based systems (e.g., CO₂, inert gas)

We want to ensure that the system is protected from fire without risking irreversible damage to the Victron equipment. Could you advise which solution would be most suitable for a garage installation in a residential setting?

Equipment List:

  • Aiko Solar Panel A-MAH72Mw 590W Comet – 10 units (MC4 connectors, silver frame, 1500V, 30mm)

  • Coplanar Roof Structure (Tile-Saver type, Ref. ST_CST_833_05V) – 2 units

  • Victron MultiPlus II 5000VA 48V – 1 unit

  • Victron SmartSolar MPPT RS 450/100 (MC4) – 1 unit

  • Victron Energy Meter VM-3P75CT – 1 unit

  • Victron Cerbo GX MK2 – 1 unit

  • Victron GX Touch 70 – 1 unit

  • Victron GX Touch 70 Wall Mount – 1 unit

  • Victron RJ45 UTP Cable (1.8m) – 2 units

  • Victron VE.Can to CAN-bus BMS Type A Cable (5m) – 1 unit

  • Victron RS485 to USB Interface Cable (5m) – 1 unit

  • Victron Lynx Distributor – 1 unit

  • Victron MEGA Fuse 125A / 80V – 1 unit

  • Victron MEGA Fuse 200A / 80V – 3 units

  • WECO 5K3XP Battery (5.3 kWh each) – 4 units

  • Battery Cable 35mm² (Black/Red) (2m each) – 1 unit each

  • Battery Fuses – 8 units

  • Battery Cable 70mm² Black (4m) – 1 unit

  • Solar Cable (Red + Black) – 1 unit each

  • Ground Cable – 1 unit

  • AC Distribution Board (6 kW) – 1 unit

  • DC Distribution Board (2/2) – 1 unit

  • Galvanized Steel Plate (130x80) – 1 unit

As end users new to Victron systems, we would also like to know what apps and tools are recommended for troubleshooting, performance optimization, and safety checks after installation.

We have found the following suggestions but would appreciate confirmation or improvements:

  • Apps: VictronConnect, VRM Portal, WECO BMS app

  • Hardware tools: Clamp meter, insulation tester, thermal camera, PV string tester

  • Software/config: VE.Configure, VRM Alerts

What tests should we requests done to prove the system is well set?

We also have a TV antenna on the roof, but we are not sure if it is properly grounded (to be confirmed). Currently, there is no lightning rod on the house, and it appears that neighboring houses do not have one either. With the addition of solar panels, so more metallic surfaces on the roof, we are concerned that the roof may now attract lightning more strongly. Could you advise if additional grounding or lightning protection is recommended for our setup?

Thank you very much for your support!!!

How to verify if Victron components are really new
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I’m not giving advice, that is in the various manuals. Just some comments:

  1. You pretty much have everything covered in terms of equipment. A BMS is vital and you would probably need a shunt. I’m not familiar with your batteries but if they have in-built BMS (they probably do), you don’t need a separate BMS and shunt.
  2. Victron recommends grounding the PV mounting frames but not the PV cells. Ensure the frames are properly grounded.
  3. What type of fuses do you have? Class T fuses are needed for the batteries. Those fuses can’t fit in the Lynx Distributor. Victron sells a Class T Power-In Lynx module for that purpose. But a single module can only hold two fuses (read batteries). There are alternatives.
  4. Do you have circuit breakers/isolators?
  5. What do you plan to do with the 70mm² battery wire?
  6. What is your panels’ VOC and ISC? How do you plan to connect them?
  7. At a minimum, I suggest reading the equipment manuals and Victron’s Wiring Unlimited. Everything is on the Victron website.
  8. You can use Node Red for further monitoring, integration and customisation. It’s part of GX. This is purely optional.

F.

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PS: My Cerbo/touch 50 came with a wall mount.

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For fire, I have a powder fire extinguisher but I have never used it, thankfully, so I can’t speak for it.

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Thank you very much Fideri for all your replies!

I’m not sure why the seller is charging separately for the GX Touch 70 and its wall mount.

To answer your points:

  1. Yes, the WeCo 5K3 XP lithium battery has a dual Battery Management System (BMS) designed for both high- and low-voltage protection.

  2. We’ll definitely ground the PV mounting frames. The installer wants to use the existing ground wire of the main electrical panel, but I assume some calculations are needed to confirm this is possible. Should we also consider adding a lightning conductor on the roof to reduce the risk of PV frames or the TV antenna being struck?

  3. Are Class T fuses / Class T Power-In Lynx module required even if the battery’s BMS handles overcurrent protection, overcharge, and discharge limits internally? Many fuses are mentioned in the installation list; I’m not sure where all of them will go, I have to ask the installer.

  4. We were told that fuses are faster than breakers. Is this true? Otherwise I’d prefer breakers if reusable. Where should circuit breakers and isolators be installed? I don’t think there is any planned/in the list, for now.

  5. The 70 mm² high-current battery cable will likely connect the batteries to the inverter to handle high continuous DC currents, which is typical for a 48 V, 5 kVA inverter system. Based on our system, the maximum continuous DC current is:

    I = P / V = 5000 W / 48 V ≈ 104 A

    During surges, current could spike up to ~200 A. A 70 mm² cable is rated for ~150–180 A (depending on insulation) and keeps voltage drop low (~1%). I read that DC battery cables must always be oversized for safety, especially with high-power inverters or large battery banks. Smaller cables may overheat, damage insulation, or trigger unnecessary fuse trips.

  6. The plan is to have 2 parallel strings of 5 panels in series, both on the south-facing roof. This configuration also provides redundancy: if one string underperforms, the other still produces.

    According to the Aiko 590 W datasheet, the panels have:

    • Open-Circuit Voltage (Voc): 53.79 V

    • Short-Circuit Current (Isc): 14.03 A

    So:

    • Total Voc: 5 panels × 53.79 V = 268.95 V, which is within the Victron MPPT RS 450/100 maximum of 450 V.

    • Total Isc: 14.03 A × 2 strings = 28.06 A, well below the MPPT maximum of 100 A. (In series, current stays the same as a single panel while voltage adds.)

    I would have loved to use panel DC optimizers with the Victron MPPT, but it seems this is not recommended because the MPPT does a similar job so would interfere? Hopefully, dirty/unusable panels / string will not limit the rest too much, otherwise we’ll have to consider other solutions.

  7. We will read Victron’s Wiring Unlimited. Are there any other useful sources for beginners? Ideally videos, as visual explanations help a lot when everything is new.

  8. Node-RED sounds very interesting, as it allows building custom dashboards, automations, and integrations on top of the Victron monitoring system. Thank you very much for suggesting it!

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Some feedback by your points:

  1. Looks fine.

  2. Grounding is very tricky because opinion is divided and local regulations differ wildly. I would suggest using or consulting a qualified local electrical engineer. Make sure to show him or her what Victron has to say about it. The topic is discussed in Wiring Unlimited. Sorry I wasn’t very clear but Victron talks of the need to protect the PV frames against lightning. You don’t want to introduce the big lightning currents into your system. So I keep lightning protection and electrical grounding separate. To make matters even more confusing, you may need surge protectors. I have one on each array and just before the power enters the house. They need grounding! Opinion is divided on mixing AC with DC grounding.

  3. Strictly speaking, fuses are not required. They add an extra but important layer of protection, in case your BMS or other equipment fail.

  4. I don’t know if fuses are always faster than breakers: I think it depends on the type. Personally, I also prefer breakers. But with batteries, I use both. Generally, breakers are more expensive than fuses. Also, unlike fuses, high capacity breakers, especially the non-polarized type, are very difficult to find. Where to place then depends on what you need to isolate or protect. Personality, I have them on each PV array (some people put them on each string), each MPPT, each battery module (non-polarized), inverter, each AC output, AC in.

  5. You only need to connect the inverter to the Lynx, not directly to the batteries. 70mm sq. wire is fine, but you may need to double up on your wire depending on what the manual recommends (another can of worms).

  6. Looks OK. I think optimizers are not supported.

  7. You could also sign up at the professional portal - professional.victronenergy.com It is free. It has some nice videos.

  8. Ok.