question

mtucker502 avatar image
mtucker502 asked

MPPT won't charge while under external con

I have two Quattro 10kva 120v in split-phase using ESS.


I connected an EG4 Communications Hub (appears as a Pylontech Battery) so that my Cerbo GX could get a more accurate SoC reading of the EG4 LifePO4 batteries. After a few minutes the MPPT controller stopped charging the batteries. I then disconnected the EG4 Communications Hub, removed disconnected devices and restored the MPPT to non BMS control. However, the MPPT will not charge the batteries at all.


If I disconnect the VE.Can cable from the MPPT it drops into standalone mode and charges as expected:

img-3936.png


If I reconnect the VE.Can cable it changes to external control and stops charging:

img-3938.png


Here are the settings on my Cerbo GX:

screenshot-2023-06-27-at-33653-pm.png

screenshot-2023-06-27-at-33703-pm.png

screenshot-2023-06-27-at-33713-pm.png

screenshot-2023-06-27-at-33733-pm.png


Here are the Quattro's settings:

veconfig1.png

veconfig2.png

veconfig3.png


Note: For some reason Phase L2 doesn't show the full ESS settings. It's missing the Cutoff voltages (all set to 47V).


For some reason I have a low battery voltage alarm coming from the Quattro.

screenshot-2023-06-27-at-33746-pm.png


My questions are:


1) Why does the Quattro report a LV alarm when the voltage is 52.54?

2) My assumption is ESS is in external control of the MPPT. If this is correct, why won't it allow the MPPT to charge?


battery chargingESSMPPT SmartSolarsmart solar charging behaviourquattro 10kva
img-3936.png (227.7 KiB)
img-3938.png (230.8 KiB)
screenshot-2023-06-27-at-33653-pm.png (94.9 KiB)
screenshot-2023-06-27-at-33703-pm.png (103.7 KiB)
screenshot-2023-06-27-at-33713-pm.png (112.5 KiB)
screenshot-2023-06-27-at-33733-pm.png (79.7 KiB)
veconfig1.png (48.3 KiB)
veconfig2.png (36.0 KiB)
veconfig3.png (39.0 KiB)
screenshot-2023-06-27-at-33746-pm.png (161.3 KiB)
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
mtucker502 avatar image
mtucker502 answered ·

I discovered that the Quattros will remain in pass-thru and the VRM portal will show them as still externally controlled even if the can-BMS device has been removed.

In order to fully recover from the EG4 Communications Hub (and I'd assume any other can-BMS you must go to Settings > Quattro > Advanced > System reset. This will reboot the Quattros and allow the MPPT to begin charging again.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Alexandra avatar image
Alexandra answered ·

@mtucker502

Every time you connect or disconnect the BMS comms you need to re boot the system. And reprogram for no bms control as you did.

You have in your basic troubleshooting shown it it the battery hub that is causing the problem.

I will start with the usual, is all the firmware on eveything up to date?

The low vattery warning is probably happening as the battery is disconnecting from the system (or opening contactors to prevent discharge) alternatively your ESS settings (dynamic cut off) are triggering that.

In the VRM advanced tab load up widgets for the battery CVL and DVL you will see what it us telling the system to do there. There is a chance the CCL from the comms is telling the system not to produce.

2 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

mtucker502 avatar image mtucker502 commented ·

@Alexandra Thank you for helping out. I'm not sure which values are CVL and DVL. Is it the System Battery Voltage:

vrm4.png

vrm5.png

Here are the widgets I have:

vrm1.png


When I disconnect the BMS from the canbus I do not disconnect the battery; it is always connected. In the graph above, I don't see where the battery voltage dropped below any of the defined values I have configured.


Which setting in VEConfigure, ESS or the Cerbo controls the low voltage alarm?

0 Likes 0 ·
vrm4.png (199.0 KiB)
vrm1.png (64.5 KiB)
vrm5.png (80.3 KiB)
Show more comments