Epever 40 amp mppt delivered

BFL13 wrote:

mike-s wrote:

MrWizard wrote:
here we go again

its NOT positive ground

it IS positive COMMON

Which are exactly the same thing. In electrical circuits, "ground" is the common reference point. For controllers which tie all the positive terminals together, that's a positive ground. RVs which tie devices to a frame connected to battery -, that's negative ground. The two don't work well together, which is the whole problem.

Nope. I have had a number of different solar controllers, some of which have said in their manuals that they have a "positive ground".

Every one of them worked just fine in the RV whether pos or neg ground internally. Every one had its neg to the Trimetric shunt neg and all was good.

You could cut it short and admit you don't understand electrical circuits. But no, you want to dig the hole deeper. No one said the mismatch couldn't be made to work if you don't try using the load control circuit with negative grounded equipment. The saving grace is that the panels themselves are typically not connected to frame ground in the power circuit. You're kludging it by ignoring the built-in load monitoring of the controller and buying an external Trimetric monitor instead.

But, it's still wrong to claim, as you have, that there's a difference between "ground" and "common" for RV circuits. In household AC circuits, the difference is in which wires carry current and which are protective. For RV DC circuits, they're the same, there is no separation between ground and neutral.