Battery-inverter cables upgrade

pudding
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Re: Battery-inverter cables upgrade

#11

Post by pudding »

That was my thinking, as long as it can apply enough force to actually crimp then what else is needed.

Next, Amphenol connectors! Good sources for ones that can crimp onto 35mm cable? Also, whose got/built the Seplos Mason kits that I intend to switch over to in a few months, do these use the same standard Ampthenol connectors as per Pylontechs so I can use the same cables?
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MrPablo
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Re: Battery-inverter cables upgrade

#12

Post by MrPablo »

From what I remember, the Pylontech batteries use 5.7mm Amphenol SurLok connectors which support 16mm or 25mm cable, but nothing larger.
I'm not sure what the Mason kits use, but if it's the 8mm connectors then there's no cross-compatibility.

Brochure here for reference:
https://www.amphenol-industrial.de/medi ... re-new.pdf
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Stinsy
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Re: Battery-inverter cables upgrade

#13

Post by Stinsy »

As I said above: the standard method to increase conductor size with pylontech is to use two sets of cables...
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3x 380W JA Solar panels (1.14kWp)
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(Artist formally known as ******, well it should be obvious enough to those for whom such things are important.)
pudding
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Re: Battery-inverter cables upgrade

#14

Post by pudding »

Yes, I think it'll be easier to get an extra set of the standard 25mm pylontech cables with that in mind and just double up the 2x25mm, and then make up 35mm cables for each of future Seplos-Mason kits. I think there was a misunderstanding before with your very first reply where you said to double up on the stock 35mm cables, that 35mm stuck in my head so I was thinking I should get 35mm cables, but doubling up the 25mm will be more than enough. Cheers! ;)
4kW array w/Fronius | 3.51kW & 3.28kW arrays w/Sunsynk 5kW hybrid | 6 x Pylon US3000C
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Stinsy
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Re: Battery-inverter cables upgrade

#15

Post by Stinsy »

pudding wrote: Wed Jan 15, 2025 10:34 am Yes, I think it'll be easier to get an extra set of the standard 25mm pylontech cables with that in mind and just double up the 2x25mm, and then make up 35mm cables for each of future Seplos-Mason kits. I think there was a misunderstanding before with your very first reply where you said to double up on the stock 35mm cables, that 35mm stuck in my head so I was thinking I should get 35mm cables, but doubling up the 25mm will be more than enough. Cheers! ;)
Sorry, I mistyped the standard pylontech cables as being 35mm² rather than 25mm²...
12x 340W JA Solar panels (4.08kWp)
3x 380W JA Solar panels (1.14kWp)
5x 2.4kWh Pylontech batteries (12kWh)
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Saladin
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Re: Battery-inverter cables upgrade

#16

Post by Saladin »

Joeboy wrote: Wed Jan 15, 2025 8:34 am If its of use to anyone. I have bought a couple of times from an ebay seller 'split charge' being their shop name. Good quality cables, many sizes.

https://www.ebay.co.uk/itm/201702388802

Hohoho..that's where I got the dodgey underspec cable I mentioned earlier. In fairness they're a distributor not a manufacturer.
I took their supplier to task and they sent me out a replacement joblot of "one-size-bigger" than what I had ordered in a batch so I wouldn't take them to court.

Assume everything you bought is one size underspec. If you get it independantly inspected or measure it accurately yourself then you most likely have a case for contention.

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GarethC
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Re: Battery-inverter cables upgrade

#17

Post by GarethC »

Stinsy wrote: Wed Jan 15, 2025 8:11 am
I'm seeing a lot more battery packs and inverters in the 80-480V range. If you're charging/discharging much faster than 100A then this seems very sensible.
Ooh where have you seen those? I'd like the 45kWh battery system I'm dreaming of installing to have 15kW inverter. To keep current to 100A, that would suggest building a 150V pack. I hadn't seen any, and was wondering about the practicality of assembling one.
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Stinsy
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Re: Battery-inverter cables upgrade

#18

Post by Stinsy »

Interesting. Did you try weighing the cable?

Copper is c. 8.96g/cm³

25mm² * 1m = 250cm³ so the copper alone in a 1m length of 25mm²should weigh 2.24kg.
12x 340W JA Solar panels (4.08kWp)
3x 380W JA Solar panels (1.14kWp)
5x 2.4kWh Pylontech batteries (12kWh)
LuxPower inverter/charger

(Artist formally known as ******, well it should be obvious enough to those for whom such things are important.)
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Stinsy
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Re: Battery-inverter cables upgrade

#19

Post by Stinsy »

GarethC wrote: Wed Jan 15, 2025 2:50 pm
Stinsy wrote: Wed Jan 15, 2025 8:11 am
I'm seeing a lot more battery packs and inverters in the 80-480V range. If you're charging/discharging much faster than 100A then this seems very sensible.
Ooh where have you seen those? I'd like the 45kWh battery system I'm dreaming of installing to have 15kW inverter. To keep current to 100A, that would suggest building a 150V pack. I hadn't seen any, and was wondering about the practicality of assembling one.
There are loads!

EG:

https://www.solaxpower.com/products/sin ... se-hybrid/
12x 340W JA Solar panels (4.08kWp)
3x 380W JA Solar panels (1.14kWp)
5x 2.4kWh Pylontech batteries (12kWh)
LuxPower inverter/charger

(Artist formally known as ******, well it should be obvious enough to those for whom such things are important.)
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Saladin
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Re: Battery-inverter cables upgrade

#20

Post by Saladin »

Stinsy wrote: Wed Jan 15, 2025 2:50 pm Interesting. Did you try weighing the cable?
I weighed it. Load tested it. Melted it at 67% "rated" continuous although that was mostly conducted heat from a fuse. Calculated the diameter of the strands x number of them. Compared it's gauge to genuine cable. Full load voltage drop tested and flagged the discrepencies on the datasheet. Like calling 35mm² 240A rated* :whako-teapot: (*@ 30% duty cycle :roll: )

Image

Janky ANL fuse. That's a ~30W heater at 100A. I use Class Ts nowadays

The lugs are shrunk as well. If you use lugs from a genuine source then they often slip off after crimping. ....One reason for this is CSA will vary in gauge depending on how finely stranded it is because you are making a circle from circles so don't expect 12 strand electrical wholesaler cable to have the same diameter as 240 strand flex..that's normal taht they won't. Lugs are designed to mate to the amount of strands not the blanket CSA. However if you get panel flex lugs on auto/welding cable they shouldn't slip off and certainly shouldn't have an entire gauge step of overhead.
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