During a thunderstorm, all three of the Quattros in the three phase system shut down and started flashing error codes 11 and 13. Restarting did not resolve the error. Turned off switches and left overnight, and in the morning everything booted up properly. Quattros are protected with SPDs and well grounded. The SPDs had not blown. But of course now the customer is worried that it will happen again. And I'm wondering what error code 13 is for as it's omitted in the list here.