Six days ago, my MPPT 250/70 suddenly stopped charging the battery.
The unit is installed in an EasySolar 2 and is controlled externally.
The PV voltage is 190 V and the battery voltage is 26.5 V, but the charging current is 0.1 A. “Bulk” is displayed.
I have checked the panels and connectors. I also performed a firmware update to version 1.74.
I carried out a hard reset as well (disconnecting the PV and battery).
The battery is no longer being charged, and the output power remains at around 30 W.
No device faults are being displayed.
How can I determine conclusively whether the MPPT 250/70 is defective, and what could be causing the problem?
You’ve already carried out the basic troubleshooting.
Depending on your skills and the measuring equipment you have available, you can also go through this:
Otherwise, you’ll need to contact your dealer/installer. They may then be able to inspect the device in more detail or, if necessary, register it with Victron.
Thank you for your reply. I had a look at the test form and basically tested the functionality according to chapter 7.
I disconnected the VE bus and the remote connection in the EasySolar and connected to the MPPT 250/70 via Bluetooth.
The PV voltage is 190 V and the battery voltage is 26.5 V; both are displayed correctly. However, no charging is taking place.
The MPPT is only connected to the battery and the PV, with no other cables connected.
So this proves that it is defective, doesn’t it?
Is it also necessary to reset it to the default settings?
I assumed that the settings would come from the GX via the VE bus as soon as an ESS is configured.
In other words, it should essentially be possible to replace it on a “plug and play” basis.
The functionality of the four-panel solar string with a constant 190 V has been verified. A contact problem is often cited, which can indeed result in a voltage reading but no current being supplied. The panels are definitely providing both voltage and current. This can be checked easily with a conventional incandescent bulb (not an LED). A 100 W bulb lights up brightly, while the PV voltage drops from 194 V to 193 V.
That seemed easier to me than performing a short-circuit test or measuring the short-circuit current (rubber gloves and a prepared lamp holder with terminals).
I disconnected the VE.Bus connection and the remote cable, but the MPPT 250/70 is still not supplying any current.