Victron Orion XS 50 amp B2B charger

On the Orion check all your cables to make sure nothing has vibrated loose, especially on the input and ground. A loose input or ground cable will cause the Orion to see a lower voltage at the input and reduce charge current. Use a multimeter to check the start battery voltage is the same as on the Orion input terminals when charging. You could check your plug in voltmeter against the VictronConnect app, but best to use one device.

For help on BMV settings see