Some things just won't sink in.

[binky]

I thought the maximum rating of MC4's was 50A which is inline with your 6mm2 cable size but not with your inverter capacity requiring 80A?

I've never looked at the MC4 specs, although most of what is supplied is MC4 compatible, so possibly higher rated?

 

[johnb2713]

I've never looked at the MC4 specs, although most of what is supplied is MC4 compatible, so possibly higher rated?

I’m not sure on that, original MC4 spec 30A, later updated to 50A. I don’t see any rated above 50A

 

[Mrjmegson]

I thought the maximum rating of MC4's was 50A which is inline with your 6mm2 cable size but not with your inverter capacity requiring 80A?

Me too. This all messed with my head. Lol

 

[Mrjmegson]

80A for how long?

No idea, the manual just says Max charge / discharge current 80A.

Which would be an issue with the MC4 connectors and the 6mm² solar cable connected to them.

 

[Mrjmegson]

Just found this ont tinterweb.

None of the MC4s provided with my system have a solid pin, so I can't see they could be these higher spec type.

 

[binky]

have a look at the tables at bottom of document, it would seem the limitation is the cable rather than the connector, and ambient temperatures.

 

[binky]

No idea, the manual just says Max charge / discharge current 80A.

Which would be an issue with the MC4 connectors and the 6mm² solar cable connected to them.

usually they state say 50A nominal with a short burst at a higher rate for a few seconds. Cable is made to withstand temporary short overloads, think the safety ratio is 2:1, don't ask me where I read that, it's a figure I've picked from the dark recesses of my mind. What kills cables is running at high loads for long periods of time, as that causes the cable to heat up and melt the insulation, hence heat resistant cable which we use for immersion heaters, for example, can carry a higher loading.

 

[johnb2713]

usually they state say 50A nominal with a short burst at a higher rate for a few seconds. Cable is made to withstand temporary short overloads, think the safety ratio is 2:1, don't ask me where I read that, it's a figure I've picked from the dark recesses of my mind. What kills cables is running at high loads for long periods of time, as that causes the cable to heat up and melt the insulation, hence heat resistant cable which we use for immersion heaters, for example, can carry a higher loading.

I've just looked at that spec sheet you posted, call me old fashioned but having contact temperatures of 105 degC would not give me confidence. Looking at the contact resistance, each pair could be dissipating 23W each. I think a nice 10 mm brass stud with decent sized lugs and washers win hands down on this one.

 

[Mrjmegson]

Well I'm just hoping the people that made the inverter know what they are doing, and 6mm² cable and an MC4 connector is sufficient.

As I've said lots before, this all blows mind.

 

[binky]

Well I'm just hoping the people that made the inverter know what they are doing, and 6mm² cable and an MC4 connector is sufficient.

As I've said lots before, this all blows mind.

You would hope so .

If that's what it says, run with it. You could always restrict outputs to something like 50amp

 

[Mrjmegson]

For those of you who don't already think I'm an utter moron (imagine that's all of you by now), be prepared to be a believer.

I just happened to open a bag of bits for the inverter while I was waiting for my chicken to cook, and looked at what I thought was the AC plug for the inverter, when I noticed on its two connections were written the words "bat+" and "bat-".

Thinking this was strange, I looked at the quick installation guide, and realised I had actually been thinking about the fox inverters, and not the new afore inverters. Moron.

So the afore inverters don't use MC4 battery connections, they use their own plug, which guess what, takes the 12mm² cable they provided.

If I had another brain cell Id be dangerous.

I've included a pic of the cable they provided with the insulation stripped back. I've never seen cable with such fine strands of wire in it. They feel like really fine nylon, and won't twist together, so getting them into a feral is an arse.

But hey, all good, nice thick cable, and no need to worry about the Amp rating of MC4s.

So basically I've wasted all your time.

Sorry. Do feel free to lay into me.

 

[Sharpend]

A genuine oversight on your part brought about a very interesting debate, so well done you dizzy brain!!!!

 

[binky]

Thank you for being honest, we get so many deceitful idiots on here. Proper flex cable that is, don't see that very often

 

[Andy1733]

Men are not suppose to read the instructions. Far easier asking other men to talk about tools, work and bits of wire/cable. It's lots more fun.
A woman's favourite question is. "What you thinking". Would they really want to know?

 

[Mrjmegson]

Cheers guys, you had every right to rip into me then, so your pleasant replies are a welcome relief.

I do enjoy a good discussion, but have to admit being a little girly in that I enjoy a good set of instructions. Unfortunately with most things being made in China and the subsequent manuals being translated into English, you seldom get a good set of instructions anymore.

Binky, is "flex cable" good? It's certainly got a nice feel too it and is very flexible and easy to work with.

Definitely requires a ferule at all terminations though, as the strands are so fine I think a screw terminal would cut it to pieces.

Thanks once again for all your help guys, I hope you know it's very much appreciated.

 

[Solarexploits]

Someone who's never made a mistake has never made anything!

 

[Mrjmegson]

Someone who's never made a mistake has never made anything!

Lol, I love that.

So does that mean I've made a huge amount of things?

 

[binky]

Binky, is "flex cable" good? It's certainly got a nice feel too it and is very flexible and easy to work with.

Yep!

 

[Mrjmegson]

I won't have enough of that cable, would TLC or CEF do it, and if so, what would I ask for, 12mm² flex cable?

 

[binky]

I won't have enough of that cable, would TLC or CEF do it, and if so, what would I ask for, 12mm² flex cable?

I would Google battery cables on line, it's not the sort of stuff electrical wholesalers tend to have. They might have meter tails in a similar type of cable, but can't think what they call them as I'm too tight fisted to pay the extra