I have been reading this link: http://www.midniteftp.com/support/kb/faq.php?id=113. It seems that my wBjR amps ship;d at some point be positive but I never see it go positive. Without any load it is flatlined at -0.1 A ( 12V system) My 24V system has the same issue at -0.2A). Any idea why? I just checked and the purple wire IS pointing toward the battery cable.
This is the correct screen I need to be referring to?
Yes, that is the correct screen...
So, it ALWAYS shows a negative current even when charging ?
Is the WB Jr. connected tightly to the shunt ? i.e. good connection ?
Always negative and nice and snug. I just checked the tightness. Whats interesting is that both systems are always negative and the 12V system when resting show -0.1 and the 24v system when resting show -0.2 which is double.
Quote from: schroew on April 21, 2021, 03:14:27 PM
Always negative and nice and snug. I just checked the tightness. Whats interesting is that both systems are always negative and the 12V system when resting show -0.1 and the 24v system when resting show -0.2 which is double.
I would have though the 24V would have been half of the 12V current but that's OK...
What if you were to connect up another charger to the battery on the Classic side of the WB Jr. ?? Does the current go positive then ?
How much current does the Classic MNGP screen say it is charging at on its main status screen ? (Not Wb Jr. screen)
It only goes positive when I apply charge power from the generator.
the 12v system reads 5A and the 24v reads 5A
In the picture, the system is in Float so you cannot expect any more current or power out of the Classic in that case.
OK, so here is a question....
With your generator OFF, do you notice an approximate 5 amp change in the WB. Jr screen current when your Classic PV is turned OFF and ON ? i.e. Does the current from your Classic and PV offset the negative 7 amps current shown in your previous picture ?
Sorry, I am not sure what you want me to do??
Quote from: schroew on April 21, 2021, 03:45:15 PM
Sorry, I am not sure what you want me to do??
Check to see if there is a difference in WB Jr. current with your solar on and with the solar off running through the classic
Heading out to the combiner box now-
With the PV off at the combiner box, the WBJR amps are ~-7.5 and now its -2.7 amps with the PV back on.
Quote from: schroew on April 21, 2021, 04:48:08 PM
With the PV off at the combiner box, the WBJR amps are ~-7.5 and now its -2.7 amps with the PV back on.
Great ! That is what I would expect.
The system was in Float charge mode from your last picture. When in Float or Absorb, you will not see maximum power from the charger.
If you were to put the Classic into Bulk/Absorb MPPT mode, OR raise the Float voltage, it would very possibly go positive amps on the WB Jr. screen...
But your batteries are charged so a little bit of negative current is expected when the battery voltage is so close to this Float voltage.
Are you using a battery temperature sensor ? That would be good. If the ratings for your batteries allow you to raise your Float voltage ever so slightly, like, 0.1 or 0.2 volts, you may see positive amperage again. I believe that may be happening when you charge from a generator... The battery voltage is being charged at a bit higher voltage through the inverter/charger or whatever you are using for your generator battery charger electronics.
I just took off the cover and physically verified the purple wire is AUX2 +
I am using a temp sensor! I will try and raise the voltage a little bit and see what happens.
Done- The Magnum inverters are taking the AC and charging the battery when I connect the generator to the AC input side of the inverter. I am off grid here and totally dependent on solar.
Hmm, no change. I am at float and it never went positive.
Try going to Absorb.
Force a bulk/Absorb and see what happens.
Also try turning off loads for a moment while doing that.
OK, I might have to wait for an opportune moment.
I got to float despite some cloudy sky and I just started the forced absorb with no loads.
Still looks negative -0.2
Where is the battery and PV negative tied to in your system ?
What is going to your battery negative besides one end of the WB Jr's shunt ?
boB
the diagram.
wbjr pic
The two 12V batteries. Ignore the other DC250-6 they are part of a different system.
AHA ! I see your problem...
Per your wiring drawing picture, move the Classic negative wire to the other side of the shunt.
The ONLY thing that should be connected to the battery negative post is the shunt itself.
That should fix it !
This would be why you saw positive current while running the generator through the Magnum inverter.
Let us know how that goes !
OH, I guess that makes sense. The shunt can't see the inbound amperage from the charge controller. Moving the negative from the controller forces the electricity to move thru the shunt. I need to do the same thing on the other system.
I am going to wait and have an electrician whip over and do this. I don't like messing around with those batteries and I think a new terminal will need to be crimped on to the wire so it will fit on the shunt.
W
By other side you mean the side opposite to the purple wire side?
Quote from: schroew on April 23, 2021, 11:04:19 PM
By other side you mean the side opposite to the purple wire side?
Yes, the Magnum side.
I think in the drawing, purple is going to the battery minus and the non-purple end is going to the Magnum negative.
That sounds right.
Would it be bad to take the negative from the bus where I have all 3 charge controllers connected and connect that to the inverter side of the shunt? The electrician are here and I am currently on hold with support but I am not sure your actually open yet. My concern is that this config will confuse the wbJR
Tech support said it would be fine to make a connection from the negative bus to the shunt. The small system for my kitchen now reports POSITIVE amperage rather than -0.2!!!
Quote from: schroew on June 04, 2021, 09:53:40 AM
Tech support said it would be fine to make a connection from the negative bus to the shunt. The small system for my kitchen now reports POSITIVE amperage rather than -0.2!!!
Great !
Would be good to have a little wiring diagram. But as long as it works that's good enough I suppose.
Thanks for reporting back.