Lipo4 battery 12v, 250A, 1920Ah

Love this stuff.

Hi everyone,
I’ve noticed my inverter making a sound while the battery is discharging and supplying power to the house. I’m trying to understand whether this is a normal operating noise or something that needs checking.
Can inverters make an audible hum or buzzing sound during discharge? Would the amount of power being drawn by the house affect how loud it gets, and could it be the cooling fan?
For anyone with a solar and battery setup, how noticeable is your inverter’s noise while discharging? What would distinguish normal operating sounds from a fault?
I’d appreciate any advice on what to look for, what information would help identify the cause, and whether this is something I should raise with the installer
. This is a fox ess inverter

Let me know what you think.

This is my diy system for my off grid diy log home I am building.

Ill clean up the wires later 😀

Just saw this on a YouTube video about a Hawaiian airbnb with a flat roof. I need something like this for my emergency temporary setup on my lawn during outages.

Looks kind of crazy for a permanent roof install. But this woman paid an install team 20K to do it.

Won't say where I'm at because I don't want the discussion to involve regulation. I'm somewhere that can't be backed to grid and I wouldn't want to anyways

My question is, if I pick up one of those off grid power stations like ecoflow 2 max delta w/ solar panels.

At a base level I guess I'd take my office and just plug everything directly into it, this should run this stuff off solar/backup just fine.

But, is there a way that I can connect this to a subsection of my house using the wall plus without effecting the grid? I know transfer switches exist, is it possible (something everyday electricians can do) to connect say a single breaker to a transfer switch so I can connect that circuit to the battery backup? Would make life a lot easier.

Sorry for dumb question, I'm struggling to wrap my head around all the solar stuff so wanted to start with something more simple like balcony/off-grid solar.

I should expand that if it's possible, what would I need to buy for an electrician to make this happen? I'd need to ensure I could afford everything before involving a professional electrician .

So I currently have a situation where I'm willing to do a DIY, but it seems very difficult (im new to solar and electric). I'm wondering if its actually worth my time, and how much I would actually save compared to buying a power station? For example a 2048 watt hour power station from a big brand might be $1000 or so. Could I make a better setup for $800? Please advise. Thanks!

Sumry 3600W 120vac 24vdc

Batteries are used K2 24v 9.6ah 245Whr (currently 27 connected, have almost 100, they were like $10 each but only paid for like 60) aluminum bars to connect them. Currently no fuses but each set of 9 will be, but the whole battery is on a breaker. I also plan to clean up cabling when I get a chance. Can fit 9 rows of 9 if I double stack them on one side without worry of them falling off.

10 harbor freight 100W solar panels in series (does about 800W) normal 400W panels are planned, I've just had these for a few years and need extra money to be able to get them.

Can run my fridge and freezer completely on solar and battery when it's sunny. Eventually want to get my server on it, but getting power to the server or Ethernet to the power is what I have to do.

This is all setup in a shed.

Just wondering could i technically run the DC solar during the day for highest efficiency. Then hook the AC side to a Bluetti elite 400 that’s plugged into my wall but also has designated solar ran to it ? Does the EG4 hybrid have a regular IEC power chord I could plug directly into the Bluetti ?

Hi, I've got a south facing fence that gets uninterrupted sun. This is in the UK. The other side of the fence is a car park area but it's quiet and for a small number of houses with designated spots and none of the spots come near my fence. So it's potentially quite a good spot for solar.

I don't think I'd be comfortable having panels that reach the ground. My current fence is 6 foot and not sturdy. It's 4 foot of fence panel and 2 foot of trellis. What I'd like to do is take the trellis off the top and have some 100W or 200W panels sloped back from the top of the remaining fence. I'm only thinking of something around plug-in solar scale. I could possibly replace the fence with 2 or 3 foot panels if that makes a better size. Solar panels wouldn't be attached to the fence but sit behind it. I am restricted from using wood for the structure otherwise that would be my choice and be quite easy. I'm thinking of making a bench like structure to be level with the top of the fence and then use an off the shelf aluminium tilting mount on top of that.

The questions are what would people use once wood is ruled out? I was looking at composite fence posts that are 70mm square. Anything metal seems to get too expensive quite quickly.

Or if there is a reasonably priced existing mount that would be even better. But mounts I've seen seem to have the leading edge quite low to the ground.

Thanks for any inspiration.

I added ten panels to my system and had to extend PV wiring to connect four panels on one row of my ground mounts to five panels on the row in front of it. I pieced together four short lengths of PV wire to make the circuit. I then had too much slack and was going to fasten the wires up to the mount after making sure the panels were making power but never did that. Last week was the wettest it has been in the two years since I installed the panels. Two of the connectors had settled to the ground touching each other. Tuesday I was mowing between the rows and notice burning wires, Yikes!! I jumped off the mower and shut off the disconnect for those panels.

There had not been any standing water, just rain and it had been clear and dry for four days. I have no idea how enough current passed through those MC4s to catch them on fire. Very fortunate I decided to mow that day. I disconnected the good connectors to isolate that section and cut out the burned connectors. I crimped on new MC4s and took out all the slack before reconnecting everything. All is good. Lesson learned, never leave any part of an install undone.

I already have a PG&E-approved 400A service/panel installed. My existing Tesla Gateway 3 is connected to one 200A section, along with my solar and Tesla Powerwall battery.

My primary goal is solar self-consumption: when my solar produces more power than the loads on the existing 200A panel need, I want loads on the second 200A panel to consume that surplus rather than export it to PG&E under NEM 3.0. And such that Tesla Powerwall 3 also backs up the second 200 amp pnale.

1. Can the second 200A subpanel be connected so its loads consume available solar generated by my existing system?
2. Will the existing Gateway 3 correctly meter and manage the power flows with both panels?
3. Does the second panel need to be downstream of the Gateway, separately metered with Tesla-compatible CTs, or connected using another Tesla-approved topology?
4. Will the second panel's loads be powered by solar when available, while the grid supplies any remaining demand?
5. Would those loads also be backed up by the Powerwall during an outage?
6. Will the proposed design preserve proper Tesla monitoring, battery operation, export control, and compliance with the approved PG&E interconnection?

any metered diagrams?

It is easy to forget the settings after making a few changes to a solar setup. Keeping a record of the battery type charging limits and low voltage cutoff settings can make it easier to figure out what changed if something does not work as expected.

Since settings vary between batteries and controllers I would not assume the same values work for every system. Do you keep a written record of your settings. Just rely on the controller’s saved configuration?

Hi everyone,

I’m planning to get into supplying solar installation consumables to installers and EPCs. There are a lot of manufacturers and suppliers of these products in my state(A state in India), so sourcing options are plentiful. I’m starting with just three products:

• Mid clamps and end clamps
• MC4 connectors
• Solar DC cable

I want to run this with zero inventory. The idea is to take the customer’s requirement (specs, quantity, delivery location), quote them, and have the manufacturer or distributor dispatch directly, so I handle sourcing, pricing and coordination but never hold stock.

I’d love advice from anyone with experience in this space:

1. Is no-stock realistic? Will installers buy from someone who doesn’t keep material on hand, or do they expect same-day availability?
2. Sourcing: with so many suppliers around, how do I pick reliable manufacturers who will do direct dispatch and give fair trade pricing?
3. Quality and compliance: for MC4 connectors and DC cable especially, what certifications or specs should I insist on (TUV, BIS, IEC, etc.)? How do I avoid duplicate or low-grade products?
4. Margins: what margins are realistic on these three items? Which one is best to start with?
5. Customers: who should I target first: local installers, EPC contractors, or rooftop solar companies? How do you win the first few orders?
6. Payments and risk: how do you handle advance payments, credit terms and returns when the goods ship from someone else’s warehouse?
7. Mistakes to avoid: anything you wish you’d known when starting out?

Plug panel in and it doesn't acknowledge this panel.

It will acknowledge the Anker 100w array panels.

This panel should be within the Anker 767's solar-input voltage range. The 767 accepts 11–60 V, and at 32–60 V it can accept up to 20 A, with a 1,000 W maximum solar input. Panel puts out appropriate Voltage per Specs. I have 2 identical powerbanks and both won't recognize the panel.

Anker SOLIX F2000 (PowerHouse 767)

Specs:

Voltage range: 11–60V

Best operating range: 32–60V

Max solar input: 1000W

Max current: 20A (above 32V)

Panel

Silfab SIL-530 XM series bifacial panel

Specs:

Vmp: ~41.05 V

Voc: ~47.79 V

Imp: ~14.08 A

Isc: ~14.96 A

Rated power: 530 W

Not sure what to do next, I heard that updating software has helped. That is my next step.

Has anyone encountered this issue?

Thank you in advance.

I'm hoping the PC app is just messing up the scaling of the info

Hi, I'm new to solar, and i bought a jackery v2 640wh power station recently.

Is there any way for me to add external batteries to this device to increase the total watt hour capacity?

If so, please share. Thanks!

Question About Grounding and Insulation Monitoring in a 48 V / 65 kWh Victron ESS (german translation below)

Hello everyone,

I would like to review the grounding and fault-protection concept of my DIY Victron battery storage system. In particular, I would like to understand whether insulation monitoring is advisable or required for my currently unearthed DC system. If an insulation monitoring device (IMD) is appropriate, I would appreciate recommendations for a suitable model.

1. Existing system

Battery storage

• 48 V LiFePO₄ battery system with approximately 65 kWh of total storage capacity
• Three battery blocks connected in parallel
• Each battery block has its own JK BMS
• The BMS units disconnect the negative path electronically using semiconductor switches (MOSFETs)
• Each battery block has an additional fuse in its positive connection
• All three battery blocks are connected to common positive and negative DC busbars

Inverters and charge controllers

• Three Victron MultiPlus-II units, rated at 5 kW each, operating as a three-phase grid-connected ESS
• One Victron SmartSolar MPPT 250/85; a second identical controller is planned
• Each charge controller will have its own independent PV array
• Two PV strings are connected directly to the parallel PV inputs of each controller
• Both charge controllers connect to the common DC busbars

PV array and grounding

• The PV strings are independent of each other and are not intentionally interconnected
• The PV module frames are electrically bonded to the mounting structure
• The mounting structure is connected to the earthing system via a protective bonding conductor
• The enclosures of all three MultiPlus-II units and the SmartSolar are connected to PE
• Neither battery positive nor battery negative is currently directly connected to PE

1. My current understanding and concerns

My initial assumption was that the DC connections of the Victron equipment are galvanically isolated from the enclosures and PE.

However, the SmartSolar MPPT 250/85 has an electrical connection between PV negative and battery negative. Consequently, the active DC circuits are not intentionally earthed, but the PV and battery sides are not galvanically isolated from each other either.

Since the PV module frames are earthed, I would like to understand what would happen if an active PV conductor developed an insulation fault to an earthed module frame.

Another concern is the JK BMS. Since the negative path is switched electronically, I want to make sure that connecting battery negative to PE would not create an unintended fault-current path bypassing the BMS switching devices.

The additional positive-side fuses are intended to protect against high fault currents. However, I understand that they may not detect or clear every possible insulation fault.

1. Questions for the community

2. Is it technically appropriate and compliant with the applicable installation standards to operate this Victron ESS with an unearthed 48 V DC system while bonding all equipment enclosures and PV module frames to PE?

3. Should battery negative or the common DC negative busbar be bonded to PE, or should the DC system intentionally remain unearthed?

4. What would be the implications of such a DC grounding connection for the three parallel MultiPlus-II units, the SmartSolar charge controllers and the JK BMS units with electronically switched negative paths?

5. How should a first insulation fault on the PV or battery side be detected? Is an insulation monitoring device (IMD) advisable or required for this configuration?

6. If an IMD is recommended, which models are suitable for a 48 V battery system with three parallel MultiPlus-II units and one, eventually two, SmartSolar MPPT 250/85 controllers? Does anyone have experience with reliable insulation monitoring in a system containing inverter/chargers and MPPT charge controllers?

7. Should the PV side also be monitored separately, particularly given the maximum PV input voltage of 250 V?

My goal is not simply to find a suitable monitoring relay, but to establish a technically sound and standards-compliant grounding and protection concept for the entire system.

Thank you for your advice and for sharing your experience!

Deutsche Übersetzung:

Frage zum Erdungskonzept und zur Isolationsüberwachung einer Victron-ESS-Anlage mit 48 V und 65 kWh Batteriespeicher

Hallo zusammen,

ich möchte das Erdungskonzept meiner selbst aufgebauten Victron-Speicheranlage überprüfen und insbesondere klären, ob bei meinem derzeit ungeerdeten DC-System eine Isolationsüberwachung sinnvoll bzw. erforderlich ist. Außerdem suche ich gegebenenfalls ein geeignetes Isolationsüberwachungsgerät (IMD).

1. Vorhandene Anlage

Batteriespeicher

• 48-V-LiFePO₄-Batteriesystem mit insgesamt ca. 65 kWh Speicherkapazität
• Drei parallel geschaltete Batterieblöcke
• Jeder Batterieblock besitzt ein JK-BMS
• Die JK-BMS schalten den Minuspfad elektronisch über Halbleiter (MOSFETs)
• Jeder Batterieblock ist im Pluspfad zusätzlich über eine Schmelzsicherung abgesichert
• Alle drei Batterieblöcke sind über gemeinsame Plus- und Minus-Sammelschienen mit dem übrigen System verbunden

Wechselrichter und Laderegler

• Drei Victron MultiPlus-II, jeweils 5 kW, dreiphasig als netzparalleles ESS betrieben
• Ein Victron SmartSolar MPPT 250/85, ein zweiter identischer Regler ist geplant
• Beide Laderegler sollen jeweils eigene PV-Generatoren versorgen
• Pro Regler sind jeweils zwei PV-Strings direkt an den parallel geschalteten PV-Eingängen angeschlossen
• Beide Laderegler werden an die gemeinsamen DC-Sammelschienen angeschlossen

PV-Anlage und Erdung

• Die PV-Strings sind untereinander eigenständig und nicht absichtlich miteinander verbunden
• Die Modulrahmen sind leitend mit dem Montagegestell verbunden
• Das Montagegestell ist über einen Potentialausgleichsleiter mit der Erdungsanlage verbunden
• Die Gehäuse der drei MultiPlus-II und des SmartSolar sind mit PE verbunden
• Batterie-Plus und Batterie-Minus sind derzeit nicht direkt mit PE verbunden

1. Meine bisherige Überlegung

Ich bin bisher davon ausgegangen, dass die DC-Anschlüsse der Victron-Geräte gegenüber den Gehäusen und PE potentialfrei sind.

Allerdings besteht beim SmartSolar MPPT 250/85 eine leitende Verbindung zwischen PV-Minus und Batterie-Minus. Damit sind die aktiven DC-Stromkreise zwar nicht absichtlich geerdet, aber auch nicht vollständig galvanisch von allen anderen DC-Stromkreisen getrennt.

Da die PV-Modulrahmen geerdet sind, frage ich mich, wie sich ein Isolationsfehler zwischen einem aktiven PV-Leiter und einem geerdeten Modulrahmen auf das Gesamtsystem auswirken würde.

Ein weiterer Punkt ist das JK-BMS: Da der Minuspfad elektronisch geschaltet wird, möchte ich sicherstellen, dass eine mögliche Verbindung zwischen Batterie-Minus und PE keinen unerwünschten Fehlerstrompfad erzeugt, der die BMS-Abschaltung umgeht.

Die zusätzlichen Plus-Schmelzsicherungen sind als Schutz gegen hohe Fehlerströme vorgesehen. Mir ist jedoch bewusst, dass sie nicht zwangsläufig jeden Isolationsfehler erkennen oder abschalten.

1. Meine Fragen an die Community

2. Ist es bei einer solchen Victron-ESS-Anlage sinnvoll und normgerecht, das 48-V-DC-System ungeerdet zu betreiben, während alle Gerätegehäuse und die PV-Modulrahmen mit PE verbunden sind?

3. Sollte der Batterie-Minuspol bzw. die gemeinsame DC-Minus-Sammelschiene an PE angeschlossen werden, oder sollte das DC-System bewusst ungeerdet bleiben?

4. Welche Auswirkungen hätte eine solche Polerdung auf die drei parallel betriebenen MultiPlus-II, die SmartSolar-Regler und die JK-BMS mit elektronisch geschaltetem Minuspfad?

5. Wie sollte ein erster Isolationsfehler auf der PV- oder Batterieseite erkannt werden? Ist für diese Konfiguration eine Isolationsüberwachung (IMD) sinnvoll oder erforderlich?

6. Falls ein Isolationswächter empfehlenswert ist: Welche Geräte sind für ein 48-V-Batteriesystem mit drei parallel betriebenen MultiPlus-II und einem bzw. künftig zwei SmartSolar MPPT 250/85 geeignet? Gibt es Erfahrungen mit der zuverlässigen Messung in einem System mit Wechselrichtern und MPPT-Ladereglern?

7. Sollte die PV-Seite zusätzlich oder separat überwacht werden, insbesondere wegen der maximalen PV-Eingangsspannung von 250 V?

Mir geht es nicht nur darum, ein passendes Relais zu finden, sondern vor allem um ein technisch schlüssiges und normgerechtes Erdungs- und Schutzkonzept für das gesamte System.

Vielen Dank für eure Einschätzungen und Erfahrungsberichte!

Hi all you Solar DIY folks,

Help me solve a problem. I have a small (12V, 5W) PV panel on my roof, that powers a recirculator pump on the ground floor for a solar hot water system (large area collector on roof, water circulates through it, 60 gallon tank).

This was installed in 2017 and worked great until last year, when all of a sudden the pump stopped. Lucky I caught it because the water in the collector would have boiled and the TPV would have blown. The lights on the pump were out so I knew it wasn't getting power. I connected a 12VDC power supply on it and it worked again just fine. Measured 160 mA on 12VDC supply.

I have lived with that setup for a year, and it's pain to turn the PS on and off every morning/evening. Off at night so water stays warm in the tank.

Today I removed the PS and reconnected the PV panel, and put an ammeter (DMM) in series. (Took this long to get a DMM, remote area.) Current was zero before sunrise, and slowly increased - 0.2 mA (not running), 0.8 mA (running slow), 0.12 A (aka 120 mA) (still slow), 0.16A (running good), 0.20 A still good, and then, bam, 0 mA not running.

Reconnected the PS and it's fine. OCV on the panel is still 18V as it should be (that's normal OCV for a 12V nominal panel).

So the only explanation I have is that when the panel warms up from the sun, some conductor or joint inside expands and loses good connectivity. But I don't know how the actual chips work so maybe something else.

I can replace the panel but it's difficult - standing seam metal roof, 3 stories up). Is that the solution?

(Grid power is not reliable here so don't suggest a timer switch on the power supply).

I have a Honda 2200 gen and a Bluetti AC70 with a 200W portable solar panel for emergency power. I used these on my previous home and just purchased a new energy efficient home with natural gas stove, gas heat, LED lighting and gas fireplace . My refrigerator specs are posted. The little Bluetti would power my older refrigerator 6+ hours and I would recharge it with the Honda. My goal is to provide power (refrigerator, a few lights, TV and router) up to 2-3 days without using the generator. I'm considering upgrading to the Solix S2000 or C2000. Should I go bigger or it this overkill? How about if I wanted to power the gas furnace too? Power outages are rare, 2-3 a year for 1-4 hours.

So looking to build out a solar and battery setup at our current house and need some advice. We're looking to move in the next 3ish years, so I want something I can take with us (minus the solar panels) and keep costs under control. This system would then be utilized as power for a shop.

Criteria:

• Automatic fail-over in the event of power outage
• Scheduling to use battery power during peak hours and charge from the grid during off hours
• Expandable capacity - I don't see doing more than 30kWh for this system, but more is nice
• Ability to stack solar and battery power to increase output

I'm comparing the new EcoFlow Titan with building out a DIY system. There are pros and cons to both. The simplicity of the Titan, having both the inverter and battery in one and a simple Smart Panel that handles everything I want starting out and then adding capacity later. The downside is cost of expansion, being locked into their batteries. I THINK WattCycle is coming out with a WattLink cable that will allow use of other batteries, but that remains to be seen. Also in the off chance something goes wrong with the inverter, you have to ship the whole unit back. In the event it dies, you lose the whole thing.

The upside of going with something like an EG4 12000 XP is much greater expansion it offers. As mentioned I plan to keep this on the smaller side and use it as a secondary system when we move, likely powering a standalone shop. The downside is its not as plug and play as the Ecoflow system and requires extra equipment to check all the boxes I'm looking for.

I suppose something like the EcoFlow Delta Pro Ultra would also work. It resolves the issue with the Titan of having the combo inverter/battery, but they're expensive compared to what you can put together yourself. The draw to the Titan is that it offers the EcoFlow simplicity and is a more manageable price with the pre-order.

I've rambled long enough, appreciate any insight and suggestions.

I added ten panels to my system and had to extend PV wiring to connect four panels on one row of my ground mounts to five panels on the row in front of it. I pieced together four short lengths of PV wire to make the circuit. I then had too much slack and was going to fasten the wires up to the mount after making sure the panels were making power but never did that. Last week was the wettest it has been in the two years since I installed the panels. Two of the connectors had settled to the ground touching each other. Tuesday I was mowing between the rows and notice burning wires, Yikes!! I jumped off the mower and shut off the disconnect for those panels.

There had not been any standing water, just rain and it had been clear and dry for four days. I have no idea how enough current passed through those MC4s to catch them on fire. Very fortunate I decided to mow that day. I disconnected the good connectors to isolate that section and cut out the burned connectors. I crimped on new MC4s and took out all the slack before reconnecting everything. All is good. Lesson learned, never leave any part of an install undone.