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Isn't captcha dead? I thought natural language processing applied to audio captcha for the blind killed it? Not to mention the captcha farms that cost $1 per 1000 captchas solved. In saying that, it might be stopping the lowest hanging fruit and that might be the majority of malicious volume...

Thanks Tom, I appreciate the link. I wanted to build one this time around so I can understand the system better. I see in your signature you have 'Solar Assistant' running on a RasPi. It looks pretty slick, how have you found it? I'm using Victron gear and have VenusOS running on a Pi attached...

I've finished my design and would love some input especially regarding the wiring and wire sizing. I don't know how to tag you guys without quoting you so apologies for that. The design has been upgraded to a 2S4P PV set up with no branch connectors as per the new uploaded image. Thanks a...

Yeah I thought about it... But geez I'll probably end up spilling acid everywhere and doing a terrible job. There's got to be someone selling tinned copper bar around here.

I just got a reply from www.ecs-online.org saying they can ship them to Australia for me. I'm just getting a quote now, I'll let you know how it goes. What do you think about the utility of 150A battery fuses? Maybe the majority of LiFePO4 batteries have a max cont. current rating of 100A, so...

Clamping voltage being the voltage that they trigger at and switch to earth yeah?

Thinking about it, it seems like I should put FOUR 10A in-line MC4 fuses on the positive connections BEFORE the positive branch connector and put a 27A (32A more likely) 2P circuit breaker in the combiner box. Does this updated wiring diagram look any more sane? Littleharbor, your post just...

Comparison of "100A" fused distribution blocks: eBay VS Blue Sea Sorry for all the pictures, I down scaled them but maybe not enough eBay BlueSea First off I love that these blocks have an integrated negative block, really clean and easy. I couldn't go back to individual blocks for...

What do you mean when you say get rid of the parallel wire? just the short interconnects between the batteries or the 2 positve and 2 negative going from the battery to the distributor? I have been looking at MRBF's as an alternative to Class T fuses. They are much cheaper and I can find good...

someone please have mercy :'(

Sorry for the very late reply. diagrams.net (previously draw.io) The high resolution images for the Victron equipment you can find on their website next to the manuals and datasheets for their products. There are some third party libraries for Victron equipment but I've never had much success...

Thanks for the input. I've drawn out the final design and just decided to go with a Lynx power in to make it a little tidier. I'm still convinced 70mm2 wire from the batteries to the Lynx is complete overkill, but can't seem to get the proper info about how long the inverter can maintain peak...

That kind of information would be very helpful. My guess is bright tinned at least 25uM layer C110 or C11000 copper will be the way to go. Thanks in advance tim

Thanks so much for the help mate. I'm pretty confident going forward with the MultiPlus II 48/5000 I'll be purchasing a Current Transformer for MultiPlus-II so I can use PowerAssist Should I change the input current limit on the Multiplus-II to 25A (Maybe less?) That Victron FAQ link was super...

Doesn't seem like a lot of consensus. I don't see any issues.

The set up I'm suggesting is 2S4P - Each of the two strings will have a total of 26.95A. Unless I'm getting my terminology incorrect I don't understand what you are saying. Is there any conventional way to calculate this? Is this just an educated guess? For a 2S4P PV set up, how many fuses...

I'm having some trouble on the AC side of things in my off-grid cabin. The RCBO's don't seem to be tripping properly. Access to the installation is limited as the property is very remote. I will try to get there in the next week but I want to come prepared. Please have look at the following...

So if using raw copper bar, give it a rough sand to remove the oxidised layer if any, then give it a fine polish, thus smoother. But if using a tin plated copper bar, would you recommend just leaving it and not sanding the surface as it'll be smooth enough and probably not be oxidised and...

What's 3.9ohms at 230v? 0.0589A > 58.9 mA - Sounds about right. I think the RCBO's would appreciate the lighter touch :) Do you suggest the resistor because it's safer/more sensible or because shorting strait to ground might be giving me strange results? I think at this stage I'm far less...

anyone?

Hello wonderful people, I’m making a PV combiner box and wanted to run some questions past you guys before I commit purchasing anything. The combiner box will be used with a 2S4P PV set up. Total number of PV panels 8.00 Total Open circuit voltage (Voc) 99.88V Total Short circuit...

Is this the data you are working off? I assume TC 25° is what you were looking at. I don't know the relevant calculations but it's the one point of the system I'm not 100% about and it's so close to the 100v MPPT voltage limit that it gives me concern. The cable run will be about 5m from the...

Thanks again Hedges, your a legend! I'll send you a picture when it's done :P

How do you guys mount your enclosures/boxes? Just screwed strait in to the wall? I want the ability to take it on and off the wall easily, are there any wall mounting kits around? What terminology should I use? VESA? Or is that more for monitors? Maybe DIN rails are the way to go? Would they...

I'll give getting tinned copper bar another go but it's proving strangely difficult in Australia. Any brand or chemical names of raw copper treatment product off the top of your head? Thanks for the help mate

bump

Yeah they do hold a crazy amount but 'm after the ability to take it on and off the wall easily

I guess the energy consumption used to regulate the temperature depends on the capacity of the system. For a full off grid over paneled house, it'd be a no brainer. For an RV/system with limited capacity, probably not. I was having a chat with someone on DIYSolar recently about what does more...

bump

With the current setup of 2 positve and 2 negative PylonTech cables running to the distributor from the batteries, the load on each cable just from the inverter will be 75A, is that right? How much would I have left in the bank for 48VDC loads? I guess 5A if I want to keep discharge at 0.8C and...

Yeah there's no need for branch connectors at all that's my bad. Don't know what I was thinking. It helped to draw a diagram. I think there are some cases where you still fuse BEFORE the combiner box in case one of the panels shorts. But thinking it through, the only time that's necessary is...

I’ve got a house and a shed that are getting panels fitted. The distance between them is 20m. The house will have 8 panels and the shed will have 4. The battery/generator room is located in the shed. I plan to have the breakers in this room. I plan to run a split set up 4s2p (house roof) +...

I say 100kg because that's the bare minimum I'd want to use in an environment that has children in it, they like to hang off things. Most of the enclosures I've seen are just boxes you screw to the wall. Maybe it's different in industrial settings. I wouldn't want to pay $300+ for an enclosure...

Thanks for your response! This is assuming all the load will come from the inverter, right? Why do we use the max continuous power and not the max peak power for this calculation? Are you suggesting the inverter is a little underrated (about 20%) to take full advantage of the batteries? 117A...

What's the calculation for surface area? When you say it'll have 2.5-3x the contact area I assume this is because of anything on TOP of the ring terminal biting down on it (washer, nut etc.) and it being attached to the stud. Is that right? Thanks a bunch Shimmy, I'm going down another vaguely...

Yeah I think I spaced out on the series parallel thing, 2S4P is definitely 4 strings of of 2 panels in series. Will I need to use inline MC4 fuses, or can all the fusing be done inside the combiner box? Will I need to fuse the strings BEFORE they go in to the branch connectors?

I don't understand. The 35mm2 cable I chose goes up to 205A Also, I thought we were meant to use peak power? Shouldn't it be 2200w/12.8 * 1.25 Yes the bus bars are made from 6mm x 20mm copper which should be good for 385A I've got 70mm2 cable in the wiring diagram Yes it's something I've...

Wow. You're going above and beyond my friend. I don't know how to thank you

The humidity seems high. How will this effect battery life? I've been logging temperature and humidity for a short while on a new LiFePO4 installation The Pylontech batteries are in an open frame rack. Everything is in a small room protected from direct sunlight and there's a fan running...

AdlerEF3 series EV fuses Can I use these fuses on a 48v LiFePO4 setup like I'd use Class-T's or MRBF's? Would they be appropriate in terms of AIC ratings and how quick they are to blow? Apparently they'll fit in a Victron Power In which normally takes MEGA fuses. Would save me screwing around...

Apologies if this is the wrong section for this post. I'm after a hand sizing up a charge controller. These are the panels I'm looking at purchasing: 320w lsc = 9.11 voc = 44.85 My configuration will be 2S2P and if I go with the bigger charge controller, this would eventually grow to 3S3P...

So the SPD in this image will take between 24 and 48 volts DC from the panels?

Here's the diagram of the test unit I'm bringing up. I'm not sure if I've done the grounding right and whether or not I should bond the neutral to ground. Thanks a bunch

I don't think I understand the distinction between a circuit breaker and a switch. Do circuit breakers necessarily have a set current at which they will pop where as a switch is purely manual in function? When would a PV array experience an over current condition? Short circuit or lightning...

Thanks for your response mate! I've looked at a bunch of different DC Max Amperage charts that range from 4AWG to 1AWG - I'll err on the side of caution and use 2AWG as you suggest. What resources do you refer to when calculating these things? I was surprised to see such variety in the charts I...

I'm still unsure what you mean why you say 125a on each post? The two batteries will be bus barred together. Are you saying both the positive AND the negative should have an MRBF? Shouldn't they both be 250a? Thank you for your time

Howdy partners, I'm drafting up a system and wanted to run it past some some of your wise minds. I've attached what could be charitably called a wiring diagram. 1. If you could point out any issues with wrong connections and/or bad wire sizing 2. Does the MPPT Battery negative connection go...

Great, thanks for saving me a few bucks :) How about setting the input current limit to 25A or less? I was reading that FAQ you linked and it also mentions "Dynamic current limiter" should I enable it? How did you get to that figure? Thanks so much

That makes a lot of sense when you put it that way, if the circuit breaks anywhere it won't flow. Thanks for all your patience and input.

Hi, I'm trying to size up fusing on a small 12v setup. Wiring diagram below. a) The battery shouldn't go over 100A discharge (I don't think I can program this in the BMS as it's a China job) b) The max current limit for the Blue Sea 12v distribution block is 100A -...

So cable sizing needs to be for the PEAK POWER off the inverter, not continuous? Makes sense. Manual says peak power is 2200watts. I don't want to take the battery over 1C discharge. I think it will damage it.

Hey maddy, Thanks for the really quick and detailed response I very much appreciate your input! I think I see what you're saying about needing to move up from a 12V system. The cable sizes and costs get ridiculous and amps the charge controller needs to be able to handle go up too. So I think...

The Victron cables are crazy expensive, can I use a generic PL2303 TTL USB-Serial adapter? I'm trying to get a VenusOS Raspi up and running and not spend $100+ on VE.Direct to USB cables. Will it work? Are there different types of the PL2303 chipset that I should avoid? I'm assuming I need to...

I'm really glad you're making me aware of this multiple battery balancing issue. I didn't have any idea. I knew about impedance matching the cables by making them roughly the same length and putting the positive and negative cables on DIAGONALLY OPPOSITE corners (if that makes sense). But I...

So if I were to fuse both poles, why wouldn't they both be 250A MRBF fuses? 2200w (inverter) + 600w (12v loads 50A max) 2800 / 12.8 = 218.75A Have I got this wrong? Thanks for the help

Thanks Hedges, So on a 12v 100AH battery: 1C would be 100A 0.2C would be 20A If we have 2x 12v 100AH batteries in parallel (2P) for a total of 12v 200AH 1C would be 200A 0.2C would be 40A How does this change with batteries in series? Are there practical limitations on what the battery post...

From the manual: 12/1200 Peak power 2200 W Minimum battery cap. 150 Ah Internal DC fuse 200 A Fuse type BF1 - 32 V Recommended wire sizing: 0 – 1.5m = 25 mm² 1.5 - 3m = 35 mm² I'll be using 35mm² wiring from the battery and to the inverter. I'll be using 16mm² to the DC loads fused at 100A...

So is this is a simple multiplication of lsc X total amount of panels e.g: 2S2P with 10A lsc would = 40A max. PV short circuit current? On the second example PV panel I gave it's listed as exactly 10A lsc, and the 150/35 charge controller lists a 40A Max PV short circuit current. Would it be...

And while I'm here ranting about bad conductor contact areas, what do you guys think about this ring terminal? It'll have 16mm2 welding cable going in to it to handle 50A. Doesn't look like a lot of meat on it... What do you think? Am I just being dramatic? A couple of alternatives I was...

Raw panel specs are in the image, that table you were looking at had a +10% safety factor on the voltage for some reason. 2S4P should be: 90.8V 21.56A 100V Location doesn't get below 0. I'll admit it's very close for comfort at 100V limit. What are your thoughts? Would the panels being second...

The RCBO is a type A with a C curve. Trips at 30mA. Would a 1M ohm resistor be appropriate? I can pick up a 0.5w or 1w from the local shop. How long should it take for the RCBO to react? We are talking ground fault/leakage and NOT over current right...

I have two of the 100AH batteries. Can I run them in parallel and I'll have a 200A continuous discharge limit? Is that enough? 2200w / 12v = 183.3A Which leaves me 200.4w for 12v loads That still seems like not enough if I had 100A of 12v loads running and the inverter hitting peak load. I...

Hi there, I was hoping someone could illustrate the differences between these two units as they look similar in a lot of ways: Multi RS Solar 48/6000 EasySolar-II 5kVA MPPT 250/100 GX They are both within a few hundred dollars of each other. Is the Multi RS a much newer product? Why is...

Might have found a solution out of Italy. Isolated 4 port USB to serial. They also sell RX/TX swapped 2.0 JST PH cables. https://www.duppa.net/shop/isolated-4-port-usb-to-ttl-uart-ftdi/?v=6cc98ba2045f https://www.duppa.net/shop/ve-direct-jst-cable/?v=6cc98ba2045f Hit me up a month from now...

Any suggestions for the type of fuse the 100A should be? Something like this? Amazon So I'm still not 100% how to hook up the BatteryProtect. Should it be between the 100A fuse and the battery positive? BatteryProtect Datasheet I also think I should be putting in a circuit breaker rated for...

Hello, I have some questions about a build I’m working on. It’s mostly Victron equipment and I wanted to make sure everything is communicating the way it should be, I also have some questions regarding isolators, fuses and cable sizing. Victron SmartSolar MPPT 250/100 Victron MultiPlus-II...

? Sorry I don't understand

Interesting. So does the surface area on top of the lug do nothing then? Even when it's sandwiched with a nut on top, it's not conducting through the stud at all? I wouldn't have guessed that. Do you remember the process for making connections with copper bar? I guess it'd involve sanding back...

I sure do

Why do we use 12.8 instead of 12v in those calculations? Also I need to factor in up to 50A of 12v DC loads not running through the inverter. So maybe a 250A MRBF? How important are MRBF's at each battery post? I only have one on the positive. From the MRBF to a MEGA fused distribution block...

bump? is there a better sub forum for this?

Can't find it. Here's a screenshot of the right hand side of draw.io You know where I can read that? Thanks a lot

Thank you, I will have to consider grounding the PV framing. The breaker should be the same as the MPPT "Max. PV short circuit current" right? Legend, thanks a bunch!

Thanks for reply. I think I'll replace the 48V setup with class T's and leave the 12V setup as is. Just need to find a way to attach a Victron M10 Class T power-in to a Victron M8 Lynx distributor

So after doing a bit of soul searching I've decided to just buy a combiner box. There's not much savings to be had with a DIY job. I was looking at the watts247 combiner you linked and it's priced pretty fairly (Some similarly priced ones on Amazon and eBay look terribly dodgy). Does it get...

I only have very limited information from the battery manufacturer and can't easily look at the BMS settings: https://werchtay.com/products/12v-100ah-lifepo4-battery-4000-cycles Thanks for the help, I have updated the diagram.

Thanks so much for the quick response. It's a no brainer, the EasySolar-II is better in every way. EasySolar-II 48/5000 = AUD $3,981.01 When I price the components individually: MPPT 250/100 TR VE.Can = $1297.10 + MultiPlus II 48/5000 = $2,351.00 MultiPlus II 48/8000 = $4,555.00 MultiPlus II...

Hi, I’m trying to get some information surrounding AIC (Ampere Interruption Rating) ratings and appropriate fuse types for LiFePO4 installations. I’m still working this all out so please let me know what I’ve gotten wrong. It seems like the extremely low internal resistance of lithium...

I can't thank you enough maddy, I really appreciate all your help and patience. I feel a lot more confident toying around with the values now. For this set up I'll be using the Risen 315w panels on a 2S2P array with a Victron 100/50 MPPT. Gets me the most bang for my buck and the max short...

Thanks for all your help Hedges! 20% sounds like a pretty fair rule of thumb. I'll definitely consider the relationship of voc and temperature in future installations.

I don't get this, why only a 50A fuse to the Victron MEGA fuse block after we parallel them? Or are you talking about the Blue Sea fused distribution board? Any chance you could look at the new wiring diagram and let me know if anything is off? This makes more sense to me. No that was...

Any recommendations on how to mate the tab of the MRBF fuse holder to the Lynx distributor? I guess an M8 nut and bolt would do the job. What type of metal for the bolt? Would you prepare the surface first? Any special washers you might use? Also just checking the MRBF fuses are bipolar because...

Also, this is the spec sheet for the welding cable I'm using. Cheers

Let's call it 12mm x 12mm x 1.6mm thickness (square) Minus the 10mm diameter hole (cylinder) 230.4mm3 - 125.66mm3 = 104.74mm3 (54.5% of 230.4) Or should I be going for surface area and not volume?

What's that got to do with anything? But yes I already have a BMV and shunt. I'm trying to set up the system in such a way that I don't go over the C rating of the battery when the inverter hit's peak loads. I'm also trying to sort out what size fuses would be appropriate. I'm also struggling...

Trying to configure a Daly BMS with 100Ah 4S1P LiFePO4 cells. After screwing around for a while I've gotten to the point where I can start changing settings within the BMS. I've been using this resource to try and make sense of it all. I've set the "Design Capacity" and "Full Charge Capacity...

Hi, I have an off-grid Victron system that runs power to a pretty conventional cabin. It’s come as a literal shock to realise the RCBO’s aren’t functioning properly. I’ve been doing a bit of reading and think this whole situation might revolve around the “External ground relay” or rather a lack...

I ordered one a couple of days ago. Looks like new stock early January.

I've read a few posts on the Victron forums where lack of isolation and ground loops were causing massive problems. I'm reasonably sure the Duppa products I linked are a quality product that doesn't have these issues. The hardware looks really good. The price is about as much as a single genuine...

1) I thought we didn't need the 250A if we had two 125A's? 2) I'm pretty sure I've got a DC switch lying around somewhere. You're right, I really should use it. 3) How much room for error do we have with the cable lengths? I still don't understand the mechanism that actually gets multiple...