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Power increased when added a second charge controller

I added 600W (24V) of solar panels to 1320W and added a 100|20 solar charger to my existing 150|70 and am now getting a huge increase in DC Power consumption. It is almost worse charging my battery than before adding the extra panels. If I shut the new panels off the DC Power goes back to normal (under 50W). When I turn them back on the DC Power increases to around 250W or more and seems to mimic the AC consumption. Is there a setting on the new controller that needs to be changed? I have experimented with a couple of settings but no change. I am at a lose at this point. Any help would be much appreciated.

dc system
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I am understanding you correctly, you added a second Victron MPPT and now your standby power usage has gone up? Meaning you are using battery power when there is no sun? Correct?

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rlp84070 answered ·

I meant to say that the "DC Power" increased when I added a second charge controller and solar panels.

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@rlp84070

Check your wiring.

How is the dc power being measured?

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rlp84070 answered ·

I meant to say that the "DC Power" increased when I added a second charge controller and solar panels.

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@rlp84070

Dc consumption? That is why i am asking how you are monitoring the consumption. Some people make the mistake of wiring the charge controller on the wrong sides of shunts etc. Or panels are dissipating the power? Are the two arrays separate?

A 100/20 does not need more than a few watts on self consumption so you either have a short or an earthing issue now.

Yes I have two completely separate arrays and the two controllers only know each other through the Cerbo GX. I have now disconnected the second controller and connected the second array to the original controller and all is working correctly now, a little over subscribed on watts but at least I'm getting the advantage of the extra panels. I may just return my second controller.
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rlp84070 answered ·

DC Power.JPG

It is being displayed on the GX Touch 50 shown in this screen print. Plus after more testing I found that none of the power from the second charge controller is going to the batteries. When I shut off the 600 Watts of panels the DC power goes back down but it doesn't change the watts going into the batteries.


dc-power.jpg (37.4 KiB)
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This sounds like something isn't wired correctly. Can you post a diagram of how the system is connected?