Inverter connection query.

sydnsue

sydnsue

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I have twin leisure batteries connected as shown in the diagram. Installing an inverter, does it matter which terminals I connect the 2 cables to?

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Thanks guys. I was checking whether I could connect to just one battery, which would have been easier with my layout, but I shall connect to both batteries as you suggest.
 
Just make sure the red wire goes to the + and the black wire goes to the -. You can't have red electrons going down a black wire, and vice-versa.

(That's a joke going back to my Physics A level class in 1967 - if you want an explanation I can write it, otherwise I won't)
 
I used two separate 25mm csa wires from my two batteries to the 200A fuse where they are parallelled, then again two 25mm csa wires from the fuse to the inverter. However, as I had some black 35mm cable (when does a wire become a cable?) I just used one black 35mm from batteries to the inverter.
Note: my + cables are orange, since they were probably made in the Netherlands where they prefer orange electrons to red ones. :ROFLMAO:
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I think they were actually £169. EACH. So they weren't the cheap ones from Amazon. :ROFLMAO:
Probably the £169 ones from Amazon, I can't remember. They do work, but I am currently thoroughly peed off that we haven't been able to use the camper this year yet. Flipping hospital and doctor appointments every week, I'm getting really angry that we 'can't" go away.
They do work in the sense that I have tested them on the driveway. They do boil a kettle, run a fan heater, and so on but I haven't used them in earnest. The Epever MPPT regulator keeps them at 13.8v (I think that's right).
There is a however, however. The Renogy is a bit peculiar. With nothing connected to the 13A socket it just shows its green LED. As soon as the habitation wiring is connected (I have three 13A sockets purely connected to the inverter, quite separate from the EHU wiring) the inverter's red LED flickers randomly. The inverter still works properly, with the red LED flickering. I checked there is nothing wrong with my habitation wiring by just plugging an extension lead into the inverter. With no load on the extension lead, the red LED flickers. I have posted a youtube showing this feature and sent it to Renogy who are investigating and will report back to me . . . . . .
 
I used 70mm cable to connect batteries together + 70mm to the inverter which is just under a metre away .I found the 35mm cable I was using was getting warm.the first battery was the live feed the past one the earth.
 

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People/ installers get hung up on cables getting warm. The amount of permissable heat that's generated in a cable (it's current carrying capacity) has been scientifically and mathematically calculated from an engineering basis and can be readily found in current capacity tables on the net, I know it seems bad to have cables getting warm but as long as you've not exceeded the current carrying capacity in a particular environment, typically open air for battery and inverter cables, there's nothing at all to worry about and you're just wasting money reducing the temperature by increasing the guage.
Losses are a different issue but there's a really useful cable loss calculator on the 12v planet website which will show you how much of your precious battery power you're wasting due to cable losses which as long as you're within the cable current carrying capacity is really more of a personal choice/opinion and not science based.
 
I have an Ring RTC1000 tyre pump (I also have an Ring RAC900 which is bigger and more powerful - so why a smaller number?) But I digress...

It has a wind-in cable with a cig lighter plug on it, which is REALLY hard to push in (makes a good fit). It draws 15 amps, which is a sensible limit for the socket.

After blowing one tyre up the wire is literally too hot to hold.

Not too hot to touch for a moment, but not something you'd want to hold hands with.

It has been like that for all the years I've owned it, and it continues to work just fine.

Ring seem to have chosen the ideal thickness for the wire, knowing the length and the load. And it runs hot, not warm.
 
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